[HN Gopher] Myanmar's satellite held by Japan on space station d...
___________________________________________________________________
Myanmar's satellite held by Japan on space station due to spying
concern
Author : giuliomagnifico
Score : 419 points
Date : 2021-03-12 18:15 UTC (1 days ago)
(HTM) web link (www.reuters.com)
(TXT) w3m dump (www.reuters.com)
| ngcc_hk wrote:
| Is there any general picture related to these and others. Old
| days most concern with geo sync etc.
| https://en.wikipedia.org/wiki/List_of_orbits
|
| Not hundreds of floating around ... I only concern in the past
| how it affects by astro photo. But if it goes back to this low
| orbit floating how these ideas come around and how to choose one
| from others.
|
| More important how it work across national boundary.
| 627467 wrote:
| As interesting as this situation is it also looks
| inconsequential. No one from burmese side has voiced anything
| (yet). Considering the political situation on the ground and how
| japan can't contact the burmese liaison it seems like this is
| just an (expensive) limbo situation.
| williesleg wrote:
| Its to monitor the environment, trust them.
| aritmo wrote:
| It looks like it is more about causing pain to Myanmar than
| actual spying concerns.
|
| Xiaomi, the Chinese consumer electronics company, which
| definitely does only consumer products, is restricted from buying
| microchips. The excuse was an award that was granted by the CCP
| to the chairman of Xiaomi, a type of award that is given away to
| 100 people EVERY year.
| trasz wrote:
| Same thing as with Huawei - when USA can't compete
| technologically, they start competing in... other ways.
| garmaine wrote:
| This was an independent decision by Japan.
| simonh wrote:
| And in fact by a single university, not even the
| government.
| lmilcin wrote:
| There is, almost by definition, no way to have business in
| China without cooperating with government. The award is
| inconsequential.
| jessaustin wrote:
| Every American consumer buys multiple products manufactured
| in China every week of her life. If this is the standard,
| we'll all be suspect. Perhaps that's the point...
| patagurbon wrote:
| That seems... High? Does every, or even _most_ people in
| the US buy non-grocery items every week? AFAIK most food is
| domestic, and I imagine most if not all the packaging for
| that is domestic as well.
|
| Sure if you buy semi-durable items: clothes, shoes,
| electronics, etc.
| dnautics wrote:
| Clothes and shoes don't even really come from china,
| either.
| shostack wrote:
| There is a substantial difference between buying a product
| from a company and running one in terms of the
| relationships the individuals have with government
| involvement and the impact on directing the company to
| support said governments agenda.
| jessaustin wrote:
| American tastes aren't totally different from Chinese
| tastes, but neither are they precisely the same. Very few
| products could be created in one place and then
| profitably sold on the other side of the globe without
| _some_ input from local marketers. If the end consumer is
| to be spared a McCarthyist show trial, what about the
| distributor? What about the importer?
|
| Besides, this is silly. Firms operating in China obey
| Chinese laws for the same reasons that firms operating in
| USA obey USA laws. If they didn't operate in accordance
| with local custom, they would not continue to operate.
| Presumably many manufacturers in China (or USA) could
| have had a "Are we the baddies?" moment, but if so they
| are now necessarily no longer manufacturers in China (or
| USA).
|
| Your fear and distrust of the Chinese government is
| perfectly rational. Even more rational would be to fear
| and distrust USA government just as much.
| shostack wrote:
| Resorting to whataboutism instead of directly addressing
| the point I made indicates you are not interested in
| discussing this in good faith.
| DigiDigiorno wrote:
| Cause Myanmar Pain?--That is not a reasonable take imo. It is a
| joint project with Japanese Universities involved. The Myanmar
| coup is very real, and it is prudent to review these things
| before making decisions anyway. After your unreasonable take,
| you segue to an unrelated China point; it feels shoehorned in.
| lostlogin wrote:
| The US government has designated Xiaomi as affiliated with the
| Chinese military. I know full well that the situation is
| complicated and there are multiple things going on. However
| it's got to be a hair splitting exercise in a totalitarian
| state, as keeping onside with your overlords requires a degree
| of cooperation.
|
| http://www.cnbc.com/amp/2021/02/01/xiaomi-sues-us-to-overtur...
| aritmo wrote:
| Xiaomi is very competitive in the consumer electronics and in
| mobile phones. They are top in sales for mobile phones in
| many countries. There is an economic war with China that
| Trump started, and Biden continues.
|
| The ban on Xiaomi is more of an attack as part of the
| economic war. The supposedly military ties due to a silly
| award were definitely shoehorned into this.
| shakna wrote:
| > The ban on Xiaomi is more of an attack as part of the
| economic war. The supposedly military ties due to a silly
| award were definitely shoehorned into this.
|
| Xiaomi's ties to the military are not _only_ expressed in
| some silly award.
|
| Several of their, and their subsidiaries, have found to
| have servers operating out of IP ranges generally assigned
| to China's APT teams and so on. (Several times. Like this
| one: [0]).
|
| It's worth noting that the reason given for adding them to
| the list of companies is to prevent the Military/Civilian
| fusion that is taken as normal when doing business with
| China. It does not stop them operating in the US - only
| investment.
|
| [0] https://blog.12security.com/wyze-essay-2-aresflare/
| known wrote:
| https://www.speedcheck.org/wiki/bssid/ can be used to track your
| location
| liquidify wrote:
| I'm curious about laws in this case. Is there 'jurisdiction' in
| space? Or is it just whoever is there can decide what they want
| to do.
| slim wrote:
| there are no juridictions outside (most) lands. these kind of
| issues are generally setteled by international treaties if
| possible, or else arbitration courts
| thaeli wrote:
| The legal framework for space is primarily laid out in the 1967
| Outer Space Treaty:
| https://en.wikipedia.org/wiki/Outer_Space_Treaty
|
| Article VI is most relevant to your question; here's a law
| review article summarizing some of the issues:
| https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1...
| mjevans wrote:
| I am not a lawyer; but the saying is something like...
| "possession is nine tenths of the law". This is much easier
| right now since currently JAXA possesses the un-deployed
| satellite.
| vmception wrote:
| I checked the article to reach that conclusion too, I was
| actually hoping it was more like space piracy where they
| captured the satellite and took it onboard. that would have
| been really fascinating!
| Rapzid wrote:
| Myanmar: That's not your satellite.
|
| Japan: That's not your government.
| jandrese wrote:
| It's a diplomatic situation. The countries will have to
| negotiate the use of the equipment. I can completely understand
| the Japanese University not wanting the equipment to be used to
| further a genocide.
| dylan604 wrote:
| What if they go ahead an launch it, but accidently
| miscalculate the orbit so it encounters a premature re-entry?
| samus wrote:
| Everybody would know what they did. They could just as well
| toss it out right now. People are not stupid.
| dylan604 wrote:
| We spent moeny to send a lawn dart to Mars because
| feet/meters were confused by some very smart people with
| lots and lots of oversight. Mistakes happen. Some are
| more expensive to learn and more embarassing than others.
| Malice is not required.
| 99_00 wrote:
| The genocide started in 2017. The Junta sized power in 2021.
| lostlogin wrote:
| Yup, and do you think that the persecution has stopped? The
| genocide which started in 2017 began with the military.
| That military has just overthrown their government (which
| itself denied the genocide).
|
| https://en.m.wikipedia.org/wiki/Rohingya_genocide
| 99_00 wrote:
| >do you think that the persecution has stopped?
|
| No I don't. What's your point?
|
| If aiding genocide was a concern Japan would have stopped
| development of the satellite at any point during the last
| 5 years.
| simonh wrote:
| The Myanmar military could pretty much do what it wanted
| in terms of military activities, but while Myanmar had an
| elected civilian government it was arguably reasonable to
| accept assurances that a civilian education institution
| was free of military interference. However now that this
| institution is controlled and run by a military
| government that is clearly not a reasonable assumption.
| 99_00 wrote:
| Which is the government that committed the genocide? The one that
| sized power or the one that was thrown out, or some other one?
| simonh wrote:
| It was done by the military, without reference to or oversight
| by any civilian government of the time, which had no say in it.
| The military in Myanmar was autonomous.
| gostsamo wrote:
| It is complicated. Long decades Myanmar was a military
| dictatorship. A few years back the dictatorship allowed
| democratic elections under the condition that it will conserve
| key positions in the government and there was this brief period
| when the country was semi-democratic. The military part of the
| government initiated the genocide, but the democratic part was
| accused for not opposing in any visible way.
|
| After the last elections, the military were supposed to loose
| some more of their positions and hence the coup.
| vmception wrote:
| and from my understanding, the military's unilateral action
| is also in line with their constitution, at least according
| to the military.
|
| so where does that leave us to form an opinion and activism
| about it? just because we have a democracy-boner doesn't mean
| we can ignore a country's constitution, even if it is flawed,
| does it?
|
| and if our democracy fervor is really so strong for us to
| actually do something about it, then its hypocritical because
| we don't do anything meaningful about it in country's that
| are more relevant, and it makes us picking on the little
| country.
| notsureaboutpg wrote:
| I think there could at least be some geopolitical
| reprecussions.
|
| The US is so willing to proscribe various Iranian
| government officials as terrorists and to sanction Iran so
| far as to deny them medicine and food from other countries,
| and they have not done anything close to resembling what
| Myanmar has done (genocide).
|
| Democracy doesn't have to be the answer but there should be
| pressure on the state of Myanmar to change in case of
| genocide. We don't have to go forcing other countries to
| accept our values (democracy, socially liberal policies /
| conservatively fiscal policies, etc.) But we should at
| least draw the line at genocide.
| kyawzazaw wrote:
| It is being argued that was not constitutional
|
| You can check this for more info:
| https://melissacrouch.com/2021/02/07/the-illegality-of-
| myanm...
|
| That professor is an expert on the constitution.
| vmception wrote:
| thanks, is there an authority or arbiter in that country
| left that people can respect, or does it now require
| external intervention
| kyawzazaw wrote:
| can you explain what you mean?
|
| There is an elected representatives that have the
| people's support.
| vmception wrote:
| A Supreme Court to clear it up, a court that people
| respect.
|
| A branch of the government thinks its actions are
| constitutional, the people and the elected
| representatives don't.
|
| Just because we are conditioned to favor outcomes that
| are more inclusive and democratic, doesn't mean it is the
| legally compliant option.
|
| Just because a scholar and constitutional expert has an
| argument, doesn't mean it is the only interpretation.
|
| So is there a court that can take the arguments from the
| scholar on behalf of the people, and the arguments from
| the military, and make a ruling?
| kyawzazaw wrote:
| No. The Supreme Court judges have been replaced by the
| military.
|
| There are no strong independent institutions.
| ecnerwala wrote:
| "So is there a court that can take the arguments from the
| scholar on behalf of the people, and the arguments from
| the military, and make a ruling?" NO. They wouldn't be in
| the current situation if they had strong functioning
| independent institutions.
| jessaustin wrote:
| _...or..._
|
| It's entirely possible for there to be no such authority
| in place, _without_ requiring "external intervention".
| In that case the people who live there might create such
| an authority, or they might not.
|
| Eventually we might realize how all humans are harmed by
| subjugation to authority.
| ehsankia wrote:
| > but the democratic part was accused for not opposing in any
| visible way.
|
| I definitely found that strange at the time, especially since
| said democratic part had previously gotten a peace nobel
| prize, but considering she was imprisoned by the military
| before and after this whole semi-democratic experiment, is it
| well accepted now that she was mostly under the control of
| the military and had very little choice in any of the matter?
| Or do people still think she was mostly complicit for not
| speaking up, at the risk of compromising the little bit of
| democracy they had.
| joshstrange wrote:
| My understanding is she feared exactly what happened, a
| coup, if she spoke out. I'm not saying that is wrong or
| right but that's the position she was in and the choice she
| made with, now proven, fears of coup. Did she have a
| choice? Of course she had a choice but it would appear she
| saw it as "be morally correct" or "maintain democracy" and
| decided to go with the latter. I hate to say it but I'm not
| sure if I would have picked a different course of action
| given the same choices.
| lostlogin wrote:
| > I'm not saying that is wrong or right but that's the
| position she was in and the choice she made with, now
| proven, fears of a coup.
|
| I am - it was wrong.
|
| Her position went beyond making a hard choice, she
| defended the genocide and the generals. Describing the
| generals involved as 'sweet' and the victims as
| 'terrorists', she is part of the problem.
|
| https://www.theguardian.com/world/2018/nov/23/aung-san-
| suu-k...
|
| https://www.theguardian.com/global-
| development/2018/nov/12/a...
| colinmhayes wrote:
| That's politics baby. If you call people you have the
| power to destroy you evil you're going to get destroyed.
| ehsankia wrote:
| Yeah, I'm not well versed enough to talk about the
| morality of it either, but I would assume that if she had
| come out against it, the military would've kicked her
| out, so they would've ended up with both a genocide and a
| coup. So it seems that it may have been a lose-lose
| situation anyways.
| 99_00 wrote:
| Which is the government that committed genocide? The one that
| lost power, the one that sized power, or some other one?
| garmaine wrote:
| It was the military that was committing genocide, and the prior
| government was unable to control them.
| elmomle wrote:
| It would seem from the language of Wikipedia
| (https://en.wikipedia.org/wiki/Rohingya_genocide, pp2) that the
| military (current group in power) bears chief responsibility--
| one thing I do know is that the military long existed as an
| independent power structure in the country. So it seems like
| they would only have driven the genocide its leaders had wanted
| to (given that this has been a deliberate, years-long
| operation). Perhaps someone with deeper knowledge could say
| more.
| flavius29663 wrote:
| on the first page of your link: The Burmese government
| dismissed these as "exaggerations"
|
| It doesn't look like the government cared too much about the
| well-being of the genocided population. This is a hallmark in
| most genocides in history. The government doesn't have to
| order a massacre, most of the times it's just doing nothing.
| [deleted]
| SirSavary wrote:
| Someone once described Myanmar to me as a "military with a
| country" instead of a "country guarded by a military".
| lostlogin wrote:
| This applies to a lot of places unfortunately.
| simonh wrote:
| Indeed, a country occupied by a hostile army that happens
| to be their own.
| joshstrange wrote:
| I'm not an expert on this but from what I've heard it
| sounds like the "government" (which, remember, had 1/4th of
| it's seats and cabinet-type positions apportioned to the
| military, by the military) might not have had a "good"
| option on how to respond to this. It appears they stayed
| silent on it for fear the military would just stage a coup
| if they spoke out. As it turns out the military did in fact
| stage a coup as soon as they saw their hold on the
| government weakening (right after the recent election and
| when the newly elected people were coming to be sworn in is
| when they executed the coup).
|
| On one hand I want to say the "government" didn't care and
| should be held accountable for not speaking up about the
| genocide.
|
| On the other hand I see how they might have been too scared
| to call it out for fear of a coup. Fears that seems to have
| been well founded...
|
| As with most things it's not black and white.
| firstSpeaker wrote:
| >>On the other hand I see how they might have been too
| scared to call it out for fear of a coup. Fears that
| seems to have been well founded...
|
| Not a good reason. Whenever I hear or read something
| about a group allowing, being silent in face of an event
| like that, I remember Srebrenica massacre [1]
|
| I clearly remember how Aung San Suu Kyi defends Myanmar
| from accusations of genocide in UN [2]. She and her
| government are as much party to the genocide as those who
| pulled the triggers. I hope I live long enough to see the
| day they are brought to justice.
|
| 1- https://en.wikipedia.org/wiki/Srebrenica_massacre 2-
| https://news.un.org/en/story/2019/12/1053221
| prashantsengar wrote:
| Of course they are a party to the genocide.
|
| But when you have to choose between the genocide of one
| ethnic communities AND the genocide but by a non-
| accountable government, you may risk choosing the former.
| flavius29663 wrote:
| The one that lost power in the coup. They were in office since
| 2016. The genocide started in 2016. This seems to be a
| complicated situation, just like it was in Syria, and anyone
| who tries to simplify it and show a single sided story is
| trying to sell you.
| kyawzazaw wrote:
| That's not actually accurate. The genocide started way before
| 2016. It started with the 1962 law and the more brutal
| cleansing in 1980s.
|
| There are a few books that I can recommend if you would like
| to read more.
| colinmhayes wrote:
| Even when Myanmar had a democratically elected government the
| military still had huge political power because the
| constitution had a clause that let them retake power whenever
| they wanted. The legitimate leader was always afraid of this
| happening, so it's quite hard to separate the two governments.
| Rule35 wrote:
| So it was a legal coup? What gives one side legitimacy?
| prashantsengar wrote:
| The Government that was thrown was elected by the people.
| This gives them legitimacy.
| supernova87a wrote:
| Well, what's the point of holding on to one satellite if anyone
| can basically buy imagery from a dozen satellite companies right
| now?
|
| Are any of those players restricting anyone from buying imagery
| of Myanmar? If no, then this is pretty much a pointless thought
| exercise for them to engage in?
| waheoo wrote:
| You can stop those companies should you need to. Good luck
| taking out their satellite after the fact.
| filereaper wrote:
| I don't want to minimize the geopolitical issue here but wanted
| to ask about microsatellites and the ISS.
|
| How do you put the satellite onto its intended orbit, like are
| only satellites intended with a polar orbit capable of this
| approach?
|
| Do you need booster rockets to get in the right orbit?
|
| Can we go the other way and use the ISS as like an orbital garage
| to capture and fix satellites?
|
| This is the first I've heard if the ISS holding onto satellites,
| I thought satellites are deployed by the launch rocket and just
| put into orbit.
| outworlder wrote:
| They have to be 'roughly' in the same orbit as the ISS. You can
| go up or down. You would't really do any inclination changes
| (if you, say, wanted an equatorial orbit) as there's no way a
| microsat would have enough fuel. Better to launch in the
| correct inclination.
|
| > Can we go the other way and use the ISS as like an orbital
| garage to capture and fix satellites?
|
| Moving the whole station doesn't really make sense. Even a
| vehicle would burn a lot of fuel, and would only really work,
| once again, in the same (or close to the same) inclination.
|
| Inclination changes are so expensive that there was at least
| one case where an operator sent a satellite all the way to the
| Moon and back, because it cost less fuel that way.
| shadowgovt wrote:
| > Inclination changes are so expensive that there was at
| least one case where an operator sent a satellite all the way
| to the Moon and back, because it cost less fuel that way.
|
| To get a good rule-of-thumb for this in your brain, you can
| think of it in terms of vector mathematics.
|
| Consider a circular orbit. Now consider two vectors: one in
| the direction of that orbit, one perpendicular to it. A naive
| inclination change from 0 degrees to 90 degrees, with no
| other change to the orbit's dynamics (i.e. same eccentricity,
| same periapsis / apoapsis), require the velocity to change
| from parallel to the first vector to parallel to the second,
| at the same magnitude. That's a total change of SQRT(2 *
| starting_velocity^2) ~= 1.4 * starting velocity. If we
| consider a velocity that is LEO (about 7.8 km/s), our total
| velocity change would have to be about 10.92 km/s.
|
| Putting a satellite into LEO from Earth's surface only costs
| between 9 and 10 km/s from gravity loss, steering, and wind
| resistance. Earth is a deceptively expensive gravity well to
| be doing inclination change maneuvers in.
| stetrain wrote:
| This really only works if your satellite is very small and you
| are okay with being in roughly the same orbit as the ISS.
|
| It is certainly not the norm for satellite launches, but if
| your mission meets the parameters and there is available space
| on a cargo supply that's already going to the ISS, you can
| potentially get a cheaper ride by going that route.
|
| As far as I know the ISS doesn't have any facilities for
| "bringing in" a larger satellite or repairing it. NASA is
| pretty protective of the ISS and objects approaching it have to
| follow very particular procedures and be certified for the
| process (Dragon, Cygnus, etc.).
|
| Also most satellites aren't in an orbit similar to the ISS.
| Things usually either get launched equitorially (east), polar
| (north/south), or are are much higher altitude in geostationary
| orbit. The ISS has a peculiar orbital inclination to make it
| more accessible to both US and Russian launch sites.
| Animats wrote:
| _This is the first I 've heard if the ISS holding onto
| satellites, I thought satellites are deployed by the launch
| rocket and just put into orbit._
|
| It's a commercial service, from Nanoracks.[1] They load
| cubesats into a container, have them shipped to the ISS, and
| the satellites are "launched" with a spring. So they're in
| roughly the same orbit as the ISS.
|
| The price just went way up. NASA raised their price on
| transport to the Space Station from $3,000 per kilogram to
| $20,000 per kilogram. They also raised the astronaut labor rate
| to $130,000/hour. NASA was subsidizing the ISS launch scheme.
| So future cubesats will probably be launched from a Falcon 9
| using one of Space-X's resellers.
|
| [1] https://nanoracks.com/products/iss-deployment/
|
| [2] http://parabolicarc.com/2021/03/05/nasa-jacks-up-iss-
| commerc...
| Defenestresque wrote:
| Interesting article. As you mentioned, NASA is justifying the
| >6x price increase with:
|
| >In announcing the policy change, NASA said it had previously
| subsidized transportation to and from the station in order to
| foster the development of commercial space applications.
|
| >"Since making these opportunities available, there has been
| a growing demand for commercial and marketing activities from
| both traditional aerospace companies and from novel
| industries, demonstrating the benefits of the space station
| to help catalyze and expand space exploration markets and the
| low-Earth orbit economy," the space agency said. "As a
| result, NASA has updated its pricing policy for commercial
| activities conducted on the station to reflect full
| reimbursement for the value of NASA resources."
|
| While I don't have any reason not to take this explanation at
| face value, I am curious about the timing. Did they just have
| too many potential customers to justify subsidizing the cost?
|
| I was also surprised to see a "trash disposal" line item in
| the price catalog. It doesn't sound like ISS-generated waste.
| Does anyone know if this is literally people paying thousands
| of dollars per kg to transport cargo to space in order to
| dispose it by burning it up on re-entry? What could justify
| such a cost? Are there examples? What kind of restrictions on
| items are there?
|
| (Perhaps I should just Google this myself! :)
| Goronmon wrote:
| _While I don 't have any reason not to take this
| explanation at face value, I am curious about the timing.
| Did they just have too many potential customers to justify
| subsidizing the cost?_
|
| That, or from a different perspective, as commercial launch
| capabilities increase, they don't want to kill competition
| by subsidizing a service that other companies want to be
| able to offer (at a non-subsidized cost).
| NortySpock wrote:
| All trash (food wrappers, paper, packaging, some medical
| waste I presume, old experiment gear, etc), and dehydrated
| sewage, currently only leaves the space station via
| visiting vessels. It requires an astronaut's time to pack
| trash, disconnect and seal dehydrated sewage containers,
| and load them into a visiting spacecraft prior to
| departure.
|
| Imagine having trash and sewage picked up only twice a
| month or once a month. That's about how often new vehicles
| visit the space station.
|
| Some uncrewed vehicles (Russia's Roscosmos Progress
| vehicle, Japan's JAXA HTV, USA's Northrop Grumman Cygnus)
| are designed to burn up on reentry. SpaceX Dragon is
| designed to make it to the ground and thus would need to be
| unpacked after splashdown.
|
| Nanoracks' Bishop airlock is supposed to offer trash
| disposal-to-orbit, but has not been used in orbit yet.
| rtkwe wrote:
| > This is the first I've heard if the ISS holding onto
| satellites, I thought satellites are deployed by the launch
| rocket and just put into orbit.
|
| Sometimes CubeSats will launch as ride-alongs on the rocket
| itself (it's more common on rockets not already going to the
| ISS) and others are designed to be launched from the ISS itself
| depending on how they're being paid for. In either case they'll
| wind up in the roughly 51 degree inclination of the ISS.
|
| > Can we go the other way and use the ISS as like an orbital
| garage to capture and fix satellites?
|
| They can't really capture satellites because very few actually
| orbit at that level it's mostly the kind of short term cube
| sats that they launch out not larger satellites. Those live in
| higher orbits so getting to them to fix is not a small task.
| Another big hurdle is the orbital inclination changing that is
| extremely expensive to do, basically everything is placed into
| it's final orbital inclination at launch because of the fuel
| requirements to change it once you're in orbit. It's why the
| ISS is at such a high inclination to begin with, so that it's
| easier to get to from Baikonur where Russia launches it's
| vehicles from.
| mcountryman wrote:
| I had to picture someone opening a window and throwing it into
| orbit haha
| Steltek wrote:
| It's actually pretty cool. They have a space torpedo
| launcher:
|
| https://en.wikipedia.org/wiki/Nanoracks_CubeSat_Deployer#/me.
| ..
|
| What I haven't figured out is how they get the sats far
| enough away from the ISS orbit with only one push.
| dylan604 wrote:
| Relativity. At the moments before launch, the ISS and
| satellite are moving at the same speed. The launch gives
| extra velocity (positive delta-v??) which ever so slightly
| due to mass differences gives a tiny push against the ISS.
| So the satellite continues to pull away with its increase
| in velocity. See Newton's first law of motion.
|
| However, after launch, the small satellite usually has no
| ability to course correct, and its orbit slowly decays to
| friction with the thin atmosphere. Meanwhile, ISS continues
| to course correct.
| pilsetnieks wrote:
| A minor nitpick but it's not relativity (as in Einstein's
| relativity,) it's just relative velocity.
|
| The launch imparts velocity on the satellite but that
| velocity difference doesn't mean it flies in formation
| with the ISS a few hundred meters or a few kilometers
| apart. If they were launched in the direction the ISS is
| going (positive delta-v), that extra velocity means a
| higher orbit; if they're launched backwards (negative
| delta-v), it'll be a lower orbit. If it's launched
| sideways, it's either higher, lower, or same depending on
| delta-v but a different inclination (angle to the
| equator.) I couldn't quickly find where exactly the
| deployer is located but I'm guessing it's aft because
| it's the same module the ISS launches it's trash out of
| now (the Bishop airlock,) and I'm guessing they wouldn't
| launch anything in a fast decaying slightly higher orbit
| just to get hit by it a few cycles later.
|
| The whole thing it's pretty cool, and it's quite new, it
| was installed only 3 months ago.
| heavenlyblue wrote:
| Wouldn't sideways launch give an orbit that sometimes
| overlap with the original orbit or is there some maths
| that makes sure that never happens?
| pilsetnieks wrote:
| Yes, twice every cycle, just at an angle, assuming all
| other orbital parameters remain the same. That's also why
| no one sane would ever do it.
| dylan604 wrote:
| Are we assuming that the satellite is going to stay in
| the same orbit? The atmo drag will constantly be applying
| pressure on the cubesat so that its orbit will always
| being decaying.
| pilsetnieks wrote:
| I don't think atmospheric drag at 400km is large enough
| to decay the orbit by half the vertical height of the ISS
| in half a cycle, though. The ISS itself with it's
| comparatively huge surface area does orbital reboosts
| only about once a month or so.[1] Also, my original
| comment was quite simplistic - a launch with a negative
| delta-v with no other course correction would result in
| an elliptic orbit with the same apogee but a lower
| perigee (and the other way around with a positive
| delta-v.) Orbits are tricky that way.
|
| [1] https://space.stackexchange.com/questions/9087/how-
| often-doe...
| saalweachter wrote:
| I assume the two confounding factors are (a) the
| satellite should be moving relative to the ISS at the
| speed it was launched, so it is going to take a while to
| come back around and (b) when it does come back around,
| it should only be going as fast as you launched it, so it
| shouldn't be nearly as dangerous as the typical orbital
| collision.
|
| [Huh, if the cubesats are launched at 90 mph from the ISS
| (the speed of a fastball), it only takes ~12 days for
| them to come back around; that's quite a bit faster than
| I would have guessed, but still probably long enough for
| orbital decay and ISS adjustments to put them out of
| line.]
| Steltek wrote:
| My understanding is that a transfer orbit requires two
| thrusts and otherwise, with only one push, all you've
| done is make for an eccentric orbit that still intersects
| your original one.
|
| Again, I'm ignorant of these things but it seems like
| depending on atmospheric drag to provide for the
| additional correction is risking a lot.
| TeMPOraL wrote:
| It is, but the intersection point doesn't track the
| station. When you push an object retrograde (i.e. throw
| it out the back), two important things happen. One, you
| make it spend more time closer to Earth than it was
| spending before, meaning extra drag, which lowers that
| orbit's closest point to your orbit, ever so slightly.
| Two, objects in lower orbits move faster, contributing to
| drag, but more importantly, meaning that once you do one
| full orbit, the object will be _somewhere else_. It may
| still roughly intersect your orbit, but you won 't be
| there when it does. Combining these two factors, you can
| give your object enough of a push that the two orbits
| stop intersecting before there's any risk of collision.
| pilsetnieks wrote:
| The eccentric orbit is the transfer orbit but yes, you
| need two thrusts to go from one circular orbit to
| another.
| genera1 wrote:
| There are even manual deployments
| https://youtu.be/-hutA7In7GA
| enriquto wrote:
| > What I haven't figured out is how they get the sats far
| enough away from the ISS orbit with only one push.
|
| What I don't understand here is how do they avoid the
| satellite hitting back the ISS? Once they are separated and
| non-propulsed, both orbits are elliptical with at least one
| point of intersection, and stay like that forever. If they
| have different period, it seems that the ISS and the
| cubesat might become arbitrarily closer in the future.
| bagels wrote:
| If you give it a few cm/s velocity, the separation distance
| grows over time.
| dylan604 wrote:
| Great, so they're essentially littering. I hope the Space
| Force Police pull them over to issue a citation. At least,
| this will burn up in the atmo rather than in a water system,
| or do they turn themselves into microparticles ultimately
| landing in the oceans? They really are litter
| bagels wrote:
| It's low orbit ~400km, the lifetime of these things is
| measured in weeks or months.
| jerf wrote:
| And the Earth picks up about 40,000 tons of space dust
| per year.
|
| We've got a lot of work to do before our space
| "littering" can even dream of matching that level... and
| that's just a coincidental level that nature happens to
| have, not some sort of threshold for "real harm", which
| I'd guess to be multiple orders of magnitude higher.
| dylan604 wrote:
| So do McDonalds wrappers is my point.
| genera1 wrote:
| It's not that far off from the truth
| ekimekim wrote:
| https://www.nasa.gov/mission_pages/station/research/benefits...
|
| Sounds like in most cases the satellites don't have any
| propulsion of their own, and are "ejected" onto their orbit
| from the ISS. Put simply, they get thrown out.
|
| I'm sure some checks are done of the orbital mechanics to avoid
| any risk of a later collission, but keep in mind that the ISS
| makes frequent course corrections to stay in orbit, and at this
| low of an orbit drag is also a factor, so simply being a
| smaller craft will cause different forces to push you onto a
| different path.
|
| Obviously this means you have very little choice in your orbit,
| but for many small satellites this isn't a concern.
|
| EDIT: To answer your "use it as a garage" point, the answer is
| that it's way too impractical. In orbital mechanics, drifting
| apart from something is far easier than getting closer to it,
| and space is really, really big. Plus keep in mind that you
| need to not only be in the same _place_ at the same _time_ ,
| but you also need to be moving at the same _speed_ (relative
| velocities in LEO can quickly reach the order of kilometers per
| second).
| filereaper wrote:
| I imagined deploying a net of some sort to get close but not
| extremely close.
|
| But I guess the high velocities mean you need a _really_
| strong and light net and the rapid deceleration might damage
| the satellite anyway.
| simonh wrote:
| Rifle bullet speed is a relatively small delta for orbiting
| craft, it goes up quite a few orders of magnitude from
| that. Pretty much anything you encounter that you didn't
| specifically try very hard to match orbits with is going to
| blast right through a net.
|
| There were studies on using the Shuttle to repair
| satellites, but aside from the maintenance mission on
| Hubble those plans were shelved. The cost of a new
| satellite was generally a lot less than the cost of a
| shuttle mission dedicated to repairing it, and it would
| often need to be dedicated due to the requirement to match
| orbits.
|
| Even if the ISS released a smallsat, which it does from
| time to time, that doesn't help you. By the time you need
| to do maintenance on it, the cubesat will have dropped into
| a much lower orbit due to upper atmosphere effects.
|
| The safest, and practically perhaps the only viable way for
| the ISS to do maintenance on orbital instruments is if they
| stay attached to the ISS.
| bzbarsky wrote:
| > it goes up quite a few orders of magnitude from that
|
| Sorry to be pedantic, but modern rifle muzzle velocities
| are in the 1.2km/s range. Escape velocity in LEO is
| 11.2km/s, so your maximal closing speed is ~22.4kms.
| Which is maybe 1.3 orders of magnitude difference, not
| "quite a few". Orders of magnitude are big.
|
| For the rest, you are right of course: we're talking
| closing speeds that can easily be one order of magnitude
| higher than rifle bullets (or armor-piercing tank
| projectiles, for that matter; those are at 1.7km/s or
| so).
| sigstoat wrote:
| > Sorry to be pedantic, but modern rifle muzzle
| velocities are in the 1.2km/s range
|
| what caliber do you have in mind for that?
| bzbarsky wrote:
| Good point. The source I was looking at was talking about
| .22 caliber rounds. I looked around some more, and that
| seems to be the general range in which you can achieve
| those velocities, though that can include discarding
| sabot versions of 7.62x51mm ammunition (with the
| projectile ending up 5.56mm or smaller).
| db48x wrote:
| What matters in a collision isn't velocity, it's
| momentum. Momentum is 1/2mv2. There's a lot of orders of
| magnitude just in the mass, but the velocities add up a
| lot faster than you'd think too. I'd say there's around
| 10 orders of magnitude between the momentum of a rifle
| bullet and the momentum of a communications satellite at
| escape velocity.
| AceyMan wrote:
| *Momentum* is m*v
|
| Kinetic energy is 1/2m*v2.
|
| #ftfy
| db48x wrote:
| Ouch, how did I make that mistake?
| Denvercoder9 wrote:
| > I'd say there's around 10 orders of magnitude between
| the momentum of a rifle bullet and the momentum of a
| communications satellite at escape velocity.
|
| That's quite an overestimation.
|
| Let's be generous and say a rifle bullet is 50 gram (0.05
| kg) and fires at 1.1 km/s, and a communication satellite
| weighs 5 metric tonne (5000 kg) and escape velocity is 11
| km/s. We have 5 orders of magnitude difference in mass
| and 1 in velocity. As momentum is m*v, total difference
| is 6 orders of magnitude. Kinetic energy is 1/2*m*v^2, so
| that gives 7 orders of magnitude difference.*
| db48x wrote:
| I'm not so sure that it is.
|
| The mass of a bullet is more like 5 grams, and the mass
| of a satellite could be around 500,000 kg (the ISS). A
| quick search shows the the largest commercial
| communications satellite is Telstar 19V, with a mass of
| 7,076kg; in my first estimate I guessed 50,000kg.
| Finally, the closing velocity of two objects in orbit
| could be up to 22.4 km/s.
|
| rifle bullet: 3x103 J
|
| Telstar 19V, geostationary orbit: 3.3x1010 J
|
| Telstar 19V, geostationary transfer orbit: 3.5x1011 J
|
| ISS, LEO: 1.2x1013 J
|
| hypothetical fast ISS: 1.1x1014 J
|
| 14-3 gives 11 orders of magnitude, but good luck making
| the ISS go that fast. Also, don't forget to add in the
| kinetic energy of the net; it's not going to be zero.
|
| Still, even 7 orders of magnitude qualifies as "quite a
| few". You don't need very many orders of magnitude before
| you have too many.
| Denvercoder9 wrote:
| The ISS is not a communications satellite, escape
| velocity is lower than maximum closing velocity, and
| kinetic energy isn't momentum.
|
| Of course you can make the statement true by changing
| everything it's about.
| db48x wrote:
| Forgive me for contradicting you, but I didn't change
| anything; I just typed momentum when I meant energy. I
| first thought of the formula, not the name, and then
| typed the wrong name. I'm not sure how I made such a
| mistake, but mea culpa. Also my old friend bzbarsky
| mentioned closing velocity, and I stuck with it when I
| made my estimate.
|
| I do agree that the ISS is not usually considered to be a
| communications satellite (though it does have plenty of
| communications gear on board, including a ham radio
| repeater if I recall correctly). But it is a thing that
| we might want to deorbit one day. Since we were
| considering the ridiculous closing velocity of two
| objects that are both on escape trajectories, I figure
| using the ridiculous mass of the ISS was fair game too.
| But like I said, I originally guessed 50t, not 400t. I
| was thinking more about the payload capacities of launch
| vehicles than the satellites themselves.
|
| Whatever mass and closing velocity you consider, 7 or 10
| or 11 orders of magnitude all qualify as "quite a few"
| even if the velocity itself only has 1.3 orders of
| magnitude of difference.
| dheera wrote:
| I guess it depends if you operate in base 2 or base 10.
| hinoki wrote:
| Naturally, you should use base e, which gives about 3
| orders of magnitude.
| dheera wrote:
| > Pretty much anything you encounter that you didn't
| specifically try very hard to match orbits with is going
| to blast right through a net.
|
| If a zombie satellite needed to be decomissioned, could
| it be shot down and left for the pieces to disintergrate
| in the atmosphere instead?
| Arubis wrote:
| If the zombie sat in question is in a _very_ low orbit,
| this can be a reasonable approach, because the
| atmospheric drag can pull the pieces down faster than
| would've occurred on an intact satellite.
|
| Otherwise, you risk just creating more high-v debris. At
| the extreme end of this, you could trigger the Kessler
| Syndrome (https://en.wikipedia.org/wiki/Kessler_syndrome)
| and make orbit practically unusable.
| jamiek88 wrote:
| Yes but then instead of one trackable, piece of junk you
| have many small pieces some too small to track.
|
| In fact the Chinese satellite destruction test in 2007
| was a very good example of this:
|
| " Anti-satellite missile tests, especially ones involving
| kinetic kill vehicles as in this case, contribute to the
| formation of orbital space debris which can remain in
| orbit for many years and could interfere with future
| space activity (Kessler syndrome).[7] This event was the
| second largest creation of space debris in history after
| Project West Ford, with more than 2,000 pieces of
| trackable size (golf ball size and larger) officially
| catalogued in the immediate aftermath, and an estimated
| 150,000 debris particles.[24][25] As of October 2016, a
| total of 3,438 pieces of debris had been detected, with
| 571 decayed and 2,867 still in orbit nine years after the
| incident.[26]
|
| More than half of the tracked debris orbits the Earth
| with a mean altitude above 850 kilometres (530 mi), so
| they would likely remain in orbit for decades or
| centuries.[27] Based on 2009 and 2013 calculations of
| solar flux, the NASA Orbital Debris Program Office
| estimated that around 30% of the larger-
| than-10-centimeter (3.9 in) debris would still be in
| orbit in 2035.[28]
|
| In April 2011, debris from the Chinese test passed 6
| kilometres (3.7 mi) away from the International Space
| Station.[29]
|
| As of April 2019, 3000 of the 10,000 pieces of space
| debris routinely tracked by the US Military as a threat
| to the International Space Station were known to have
| originated from the 2007 satellite shoot down.[30]"
|
| https://en.wikipedia.org/wiki/2007_Chinese_anti-
| satellite_mi...
| dheera wrote:
| I see. What about a huge orbiting ball of butter* with
| thrusters that just slowly changes its orbit and sweeps
| all the trash by getting the trash embedded in itself?
|
| * not actual butter, but you get the idea, some polymer,
| or maybe aerogel?
| csunbird wrote:
| Space is huge. You probably would need a very, very large
| sweeper to collect anything.
| Arrath wrote:
| Relative velocities are just a huge problem. Unless the
| object and the catching item are moving near the same
| speed, chances are the debris will just punch through the
| item meant to catch it and keep trucking (and maybe make
| more debris in the process)
| LASR wrote:
| It would be like trying to catch a hypervelocity meteor
| with a net. It would go right through any kind of
| reasonable(or even extreme) net material.
|
| Keep in mind that when the atmosphere is used to "catch" a
| returning spacecraft, it takes several minutes of sustained
| deceleration over thousands of miles, and in the process
| the craft gets extremely hot due to compressive heating and
| friction with air.
|
| When you have satellites on different orbital planes, it
| can be twice as hard due to relative velocities.
| jiofih wrote:
| The ISS orbits at 400km altitude and 27000km/h, while many
| small satellites will orbit lower - I suppose this is what
| makes it possible to "drop" a non-propulsive satellite from
| the ISS like the one in the article.
|
| As their orbit decays, they would actually need tons of
| fuel to _accelerate_ and raise their orbit to reach the
| station, it's totally impractical.
|
| EDIT: not geostationary
| viklove wrote:
| That doesn't make any sense. If you want to orbit at a
| lower speed, you need to increase your altitude.
| Geostationary orbit is at 35,000+ km, while the ISS
| orbits at ~400 km.
| madpata wrote:
| Don't you mean much higher? Like at 36MM/36,000km?
| hnuser123456 wrote:
| Geostationary orbits are much higher altitude to achieve
| lower orbit speeds. Gravity is stronger closer to the
| surface. But they'd still need a lot of fuel to slow
| down, to drop lower to the ISS' orbit, and then they'd be
| on an elliptical, and need even more to circularize and
| rendezvous.
|
| edit: I'm the third one to say this in a span of a
| minute, sorry.
| gpav wrote:
| Instead of geostationary, I think you mean low earth
| orbit (LEO). There is a link to the Wikipedia article on
| LEO in an adjacent comment. A circular geostationary
| orbit is at an altitude of 22,236 miles/35,786
| kilometers.
|
| https://en.m.wikipedia.org/wiki/Geostationary_orbit
| [deleted]
| ryandrake wrote:
| Yea a few Kerbal Space Program sessions were enough to
| convince me that it's totally impractical to have a
| "collector" spacecraft that just goes around collecting old
| satellites and space trash in different orbits.
| m4rtink wrote:
| Depends if you cann make the economic (material reuse in
| orbit) or safety case (eliminate collision risk) there a
| couple thing that can be done for an Earth-like planet
| (lots of sunlight + atmosphere) to make itbwork:
|
| - setup orbital refueling of your tug - if you have enough
| time, let the tug drift by gravity anomaly and sun
| influence as optimal - use electric engines as much as
| possible to reduce fuel mass needed - make the thing
| aerodynamic enough to enable aerobraking or even orbit
| plane changes - add tethers for even more momentum transfer
| magic
|
| These tricks could make the proposition of capturing and
| reusing dead satellite much more viable when applied. :)
| saalweachter wrote:
| The material reuse intrigues me.
|
| De-orbiting satellites -- while necessary for well-
| discussed reasons -- seems _wasteful_. You spent umpteen
| million dollars getting that mass into orbit, and you 're
| just going to drop it?
|
| It's kind of like the plans to throw nuclear waste into
| the Sun, or more realistically into a deep ocean
| subduction zone -- isotopes that heavy or unstable are
| _rare_ , do you know how much work it is to find them?
| Fordec wrote:
| Yeah, I'm not at all convinced of the garbage man satellite
| idea. The Delta-V calculations only make sense if the craft
| is very big. And all the very big ones are in GEO, not LEO,
| where it's even harder to achieve.
|
| Lasers that act as a long term external pressure for small
| stuff, maybe. But the laser strength, object tracking and
| object targeting tech still has a long long way to go
| before that is viable.
|
| Reduce, reuse, recycle. In that order. We need to start
| applying it to space too. The most viable path to reducing
| space debris right now is not creating it in the first
| place. Through reusable rockets, miniaturization, and
| removing mechanisms that give off less debris during
| operation like stopping the use of explosive bolts or
| reducing the need for protective coverings. Lowering the
| regulated maximum 25 year lifespan of a satellite further
| would also be an option.
| Apofis wrote:
| Oh it's entirely possible. Space
| Infrastructure Servicing (SIS) is a spacecraft being
| developed by Canadian aerospace firm MDA to operate as a
| small-scale in-space refueling depot for communication
| satellites in geosynchronous orbit.
|
| https://en.wikipedia.org/wiki/Space_Infrastructure_Servicin
| g
|
| and also OSAM-1 (short for On-orbit
| Servicing, Assembly, and Manufacturing 1), a robotic
| spacecraft equipped with the tools, technologies and
| techniques needed to extend satellites' lifespans - even if
| they were not designed to be serviced on orbit.
| During its mission, the OSAM-1 servicer will rendezvous
| with, grasp, refuel and relocate a government-owned
| satellite to extend its life. But OSAM-1's effect will not
| end there. The benefits are many. OSAM-1's
| capabilities can give satellite operators new ways to
| manage their fleets more efficiently, and derive more value
| from their initial investment. These capabilities could
| even help mitigate the looming problem of orbital debris.
|
| https://nexis.gsfc.nasa.gov/OSAM-1.html
| stingrae wrote:
| If you plan for it can and has been done though at least
| for a single satellite. The Space shuttle serviced Hubble
| several times https://hubblesite.org/mission-and-
| telescope/servicing-missi...
| ericbarrett wrote:
| The issue isn't launching to intercept a body in orbit,
| though--in those missions, the shuttle was launched at
| the Hubble. Just that wandering between orbits to
| "collect" debris and satellites en masse is not really
| feasible with rockets as we know and build them.
| Aperocky wrote:
| rendezvous is quite easy. Just needs deltaV.
| TeMPOraL wrote:
| KSP gave me the exact same impression, but there's one
| thing I wonder about: with sufficiently smart global
| optimization algorithm, maybe a collector craft _could_
| approach and collect several targets on a low Dv budget? It
| 's not something you could do manually, but space has also
| this nice property that you can predict trajectories
| accurately far in advance, so it may be amendable to
| optimization.
|
| Wonder if there's a paper somewhere that computed possible
| Dv requirements for a collector if you squeeze your flight
| plan very tight.
|
| (Also in-orbit refueling will change this equation a lot.
| You could keep a bunch of such collectors continuously in
| space, and wait for the trash to align right. There's no
| hurry.)
| gmueckl wrote:
| Assuming you manage to grab a hold of debris without
| ripping off even tiny parts, how would you dispose of it?
| You'd need to deorbit it and you need a working engine
| for that. So a reusable collector doesn't seem like a
| plausible concept to me.
| lambda_obrien wrote:
| Shoot it with a dart that has a really long wire attached
| to it, then release the wire to drag in atmosphere, so
| the satellite is slowly pulled down?
| CompuHacker wrote:
| You can attach a wire to an object in Earth orbit and use
| the magnetic field of the Earth to change that object's
| orbit over time, as well.
| lambda_obrien wrote:
| That's an interesting idea, I wonder if you would need a
| loop or a winding method to get enough counter-emf?
| morlockabove wrote:
| There are at least some proposals that use ionised
| particles in the earth's upper atmosphere as a conductive
| elements, meaning you don't need a loop as such- just a
| wire pointing towards the earth with a big metal ball on
| the end. Lorentz force means you can accelerate prograde
| or retrograde.
| SyzygistSix wrote:
| Why does it need to be deorbited? Why is collected and
| held not effective?
| TeMPOraL wrote:
| > _Assuming you manage to grab a hold of debris without
| ripping off even tiny parts_
|
| There are some ideas that could be repurposed from
| asteroid mining concepts. Many asteroids are more like
| pile of gravel loosely bound by gravity than solid rocks,
| and either way, trying to extract anything risk launching
| lots of tiny pebbles in a random directions. One idea I
| saw floating around NASA website was to wrap such an
| asteroid in a net or sheet of material, to keep it from
| shaking itself apart. I could imagine similar lightweight
| net being used to wrap a satellite.
|
| Once wrapped, you can do two things with it. You can try
| to deorbit captured trash - for instance, with a light
| net and a solar sail attached (which would be used to
| increase atmospheric drag). Such trash would not only
| deorbit faster, but a sail would make it easier to track.
| Nets and sails would have to be light and disposable,
| they could be shipped to orbit in bulk, or (later)
| manufactured in space.
|
| Alternatively, you can try to recycle the trash. If you
| have in-orbit refueling using propellant sourced from
| space, you probably already have - or are about to have -
| some facility in orbit that could reprocess parts of dead
| satellites. So you can move the trash to some designated
| recycling orbit.
|
| --
|
| Now that I think of it, you could probably make a
| recycling collector work without all the infrastructure
| in space. In orbit, you have time, you can take things
| slow. I can imagine a collector chasing light trash using
| ion thrusters, or whatever is most promising in high-Isp
| department these days (how small can a VASIMR get
| anyway?), grabbing it and parking at the recycling orbit.
| Might take weeks per piece of trash, but if you launch a
| bunch of such collectors and feed them trajectories from
| the ground, they'll eventually clean the orbit out of
| light trash. It might require some actual developments in
| the beamed power department, and perhaps launching a
| power satellite to microwave some electricity to the
| collectors, but think it would work in (sufficiently
| modded) KSP :). Anyway, the biggest problem isn't mission
| design, but figuring out who will actually pay for this.
|
| Not sure what to do about the most dangerous space trash
| - the tiny bits that can't be reliably tracked. Track
| them better and vaporize with lasers?
| morlockabove wrote:
| 'Laser brooms' are one idea. I think you still have to be
| able to resolve the debris, but the idea is to end up
| causing assymetric light-induced thrust on the debris,
| deorbiting it faster (by heating the prograde side).
|
| Another very 'interesting' idea is deploying a large
| amount of fine dust on an appropriate polar orbit.
| Everything intersecting that orbit will be sandblasted,
| increasing drag; this will have the greatest effect on
| the smallest debris, and hopefully anything operational
| in that orbit will be well enough armored or able to
| dodge the cloud. The dust deorbits quickly for the same
| reason as the tiny debris (greater surface area/volume).
| One of the more metal ideas for space debros handling
| I've heard.
| sigstoat wrote:
| > Assuming you manage to grab a hold of debris without
| ripping off even tiny parts, how would you dispose of it?
| You'd need to deorbit it and you need a working engine
| for that.
|
| meet up with the debris, reorient yourself and the debris
| such that the debris is closer to the earth (reaction
| wheels, magnetic torquer bar and patience is all that's
| required), and then just mechanically kick it down (store
| up energy from the sun and then trigger a solenoid). the
| debris itself becomes your propulsion. you get a tiny
| boost up, perhaps towards your next target, and it gets a
| (admittedly!) tiny boost down.
|
| obviously it doesn't instantly dispose of everything, but
| progressively pushing material further down the gravity
| well is the next best thing.
|
| not claiming this would be cost effective.
| Denvercoder9 wrote:
| > then just mechanically kick it down (store up energy
| from the sun and then trigger a solenoid). the debris
| itself becomes your propulsion. you get a tiny boost up,
| perhaps towards your next target, and it gets a
| (admittedly!) tiny boost down
|
| This doesn't actually work. If you push something down in
| orbit, you just make its orbit elliptical. After half an
| orbit it will be at the same altitude as you again, and
| after a full orbit it will hit you from the top. If you
| want to lower its orbit, you need to push it back.
|
| Orbital mechanics is weird.
| craftinator wrote:
| > This doesn't actually work. If you push something down
| in orbit, you just make its orbit elliptical.
|
| Came here to say this as well! The only caveat to that I
| can think of is if you're already low enough in orbit,
| the push making the satellite's orbit elliptical could
| put it in a drag zone, and then air would do the slowing
| down for you.
|
| Also, thank you Neal Stephenson for introducing me to the
| wonderful would of orbital mechanics via Seveneves!
| narism wrote:
| Also plays a role in another of his books, Anathem.
| shkkmo wrote:
| For me, accidentally losing contact with the space ship
| during a Kerbal space walk taught me exactly how tricky
| manual orbital piloting is and inspired me to learn more.
|
| The Kerbal never got back to his ship before running out
| of propellant.
| sigstoat wrote:
| > If you want to lower its orbit, you need to push it
| back.
|
| if you want to lower its orbit, you probably need to take
| a lot of complicated stuff in to account which doesn't
| fit into a comment. i won't charge the orbital
| dynamacists implementing my idea more if they replace
| "down" with "the optimal direction for this target, at
| the optimal moment".
|
| mass of the target, cross sectional area of the target,
| any out gassing it might be doing, where we're trying to
| maneuver to next, etc, etc.
|
| if the optimal direction ends up being exactly "down" or
| "back", i'll buy you a beer.
| shkkmo wrote:
| As a general rule of thumb, the only way to decrease the
| energy of an orbit (what most people would consider to be
| "lowering the orbit"), is to apply acceleration in the
| opposite direction that the object is traveling.
|
| You may be to do this with atospheric drag if you add
| enough ellipticity but they would only be lowering the
| orbit indirectly.
| sigstoat wrote:
| > would only be lowering the orbit indirectly.
|
| you know, in the wildly hypothetical world where this was
| implemented, i don't think the folks cutting the check
| would mind if you deorbited things directly, or
| indirectly.
| jniedrauer wrote:
| But you could just kick it in the retrograde direction
| and to de-orbit it. In fact you could use centrifugal
| force and a cable to generate a significant amount of
| acceleration using reaction wheels powered by solar
| panels which would not consume any propellant.
| [deleted]
| ramses0 wrote:
| Clever! A 'hopper' bot. Capacitor + Discardable Mass ==
| Thrust.
| m4rtink wrote:
| You could attach a simple lightweight drag sail or a Echo
| style very low pressure balloon. That can increase drag
| of the thing by orders of magnitude and get it down
| _fast_ while you tug goes for the next target or returns
| for refueling or restocking.
| dredmorbius wrote:
| There are some interesting ways of adding drag to
| objects.
|
| Increasing surface area will (eventually) de-orbit due to
| drag.
|
| The wire methods mentioned earlier could possibly offer
| the option for magnetic / induction drag.
|
| Ion engines are an option, though they're spendy.
|
| Geosync orbit is the tough one. It's much larger, but the
| sweet spots (equatorial orbits) are relatively scarce.
|
| Mandating methods of clearing critical orbits (for GEO)
| or deorbiting (for LEO) implemented prior to deployment
| is probably the more viable option.
| gmueckl wrote:
| Self-disposing satellites are a good idea, but it's not
| perfect. If the control unit or the engines of the
| satelite fail too early during the satellite's life span,
| the thing will simply stick around.
| dredmorbius wrote:
| Right. And this actually _is_ rocket surgery.
|
| There's also the problem of retaining propellants over
| long periods without experiencing some negative
| consequence (detonation, unintended firing,
| volatilisation, etc).
|
| But in general, minimising the special-handling cases
| would be an improvement.
| TeMPOraL wrote:
| Long-term propellant issue could probably be solved by
| using a cold-gas thruster with a non-reactive propellant
| - basically a pressurized gas tank welded to a valve and
| a nozzle. It should have enough Dv to push you into a
| graveyard orbit, or even deorbit straight from GEO
| (though that's probably dangerous, and I imagine you
| could see spectacular fireworks from the ground, as the
| satellite would be hitting the atmosphere with a couple
| km/s more velocity than it's typical).
| m4rtink wrote:
| Thankfully GEO is still a bit self cleaning as Sun and
| Moon influence makes it unstable - you can clearly see it
| in orbital debris models, there is a blurry plane shifted
| ring around the primary GEO stripe.
|
| Still that will only prevent a dead sat in sitting in a
| valuable spot for ever, it migh still drift the wrong way
| and require active sats to do avoidance maneuvers, not to
| mention the chance of two inactive sats colliding.
| tomc1985 wrote:
| Could an astronaut grab a smaller satellite and simply
| chuck it towards the sun? Would it have enough velocity
| break out of earth orbit or would it just get stuck in
| some really large, wide, graveyard orbit?
|
| If not the sun then maybe the earth?
|
| That would be a fun spacewalk.
| AngryData wrote:
| To fall into the sun you would have to negate most of
| Earth's orbital speed which is about 29.8 kilometers per
| second. To escape the solar system you need about 42.1
| km/s of speed. It actually takes less energy to yeet
| yourself out of the solar system from Earth than to fall
| down into the sun. If you threw an object from Earth's
| orbit along Earth's orbital path an extra 12.3km/s that
| object would be going 42.1 km/s and eventually but barely
| leave our solar system.
|
| Unfortunately throwing things at kilometers per second by
| hand is not possible, 1 km/s is just under 2237 mph.
|
| Of course with atmospheric drag for most low orbit
| satellites things will come down eventually, in which
| case throwing something the right way could add or
| subtract from the time it will stay in orbit, but that
| would be highly dependent on where you started. And LEO
| is already like 7.2 km/s or about 16,000 mph. Standing on
| a massive enough satellite using a large stick or like a
| sling staff would certainly help you get more speed in
| your throw though. A 100 mph baseball throw really
| wouldn't be that significant though.
| DavidSJ wrote:
| The [?]v to escape Earth orbit is generally quite large,
| and it's far, far greater still to collide with the Sun
| (though this wouldn't normally be considered necessary).
|
| In comparison, a deorbit burn is usually relatively
| inexpensive.
| [deleted]
| taejo wrote:
| From low Earth orbit, delta-v to Earth and to escape the
| solar system are about the same. Delta-v to fall into the
| sun is two orders of magnitude bigger.
| labawi wrote:
| Directly. Not if you take it the long way - near escape
| to reduce orbital speed, a little push to cancel the
| rest, and you will fall directly into the Sun (with a
| high velocity).
| dmoy wrote:
| It would be difficult for an astronaut to chuck an object
| with over 32,000m/s of delta-v.
|
| For comparison, the fastest bullets go like ~1,500m/s,
| and they are very very very small.
| tomc1985 wrote:
| If I chuck a baseball out of an airplane I don't have to
| worry about accelerating the baseball to the airplane's
| speed, as I am also traveling at that speed.
|
| Similarly, if a satellite is light enough in low-G to
| grab and manipulate from a craft that has straddled up
| along side it, would a single astronaut have enough
| strength to use his arms to put a satellite on a path
| that is effectively out of the way? Or could they just
| chuck it back at the earth so it can burn up on reentry?
| TeMPOraL wrote:
| > _If I chuck a baseball out of an airplane I don 't have
| to worry about accelerating the baseball to the
| airplane's speed, as I am also traveling at that speed._
|
| But the speed of the baseball you just thrown out will be
| (ignoring air friction) that of the airplane +/- 40 m/s,
| assuming you're some super strong thrower.
|
| > _if a satellite is light enough in low-G_
|
| Microgravity doesn't mean the satellite is light now. It
| still has the same mass, it's just that you're _both_ in
| free fall, so it doesn 't pull away from you. For the
| purpose of throwing it, the satellite is just as hard to
| throw as it would be on the surface of Earth.
|
| But even assuming it weighs as much as a fastball, when
| you throw it super hard, you'll change its velocity by...
| 40 m/s at best. Compare that with the orbital speed,
| which is many _kilometers_ per second (e.g. about 7.6 km
| /s if you're on ISS). So e.g. instead of going 7.6 km/s,
| the thrown satellite now goes... 7.56 km/s. Which
| translates to one end of the orbit dropping by a couple
| hundred meters. So instead of 408km, it'll now go as low
| as... 407.5km, or something in that ballpark.
|
| That's the limit of what you can achieve by just tossing
| things with muscle power.
| dmoy wrote:
| edit: it's 24k, not 32k, I had the wrong number initially
|
| edit2: actually now I'm not so sure, I might have had the
| right number initially. It's either 24k or 32k. Either
| way it's impractical.
|
| 24,000m/s is the difference in speed that the astronaut
| is already traveling with the speed necessary to get to
| the sun
|
| Getting to the sun is really hard.
|
| Chucking it back into the atmosphere is much easier, but
| GP was asking about throwing things into the sun.
| darkwizard42 wrote:
| I think the goal would be to first accelerate the
| astronaut to that level of velocity and then relatively
| adjusting its trajectory isn't so difficult. But, that is
| just my understanding that speed is relative (especially
| in space with no drag)
| morlockabove wrote:
| Speed is also extremely expensive due to the rocket
| equation- changing your velocity, that is.
| dmoy wrote:
| It would surely be easier to accelerate space trash into
| the sun than it would be to accelerate both the astronaut
| and space trash into the sun.
|
| I don't think we should do either of those, but less mass
| is always easier to speed up.
| JshWright wrote:
| It takes a "huge" amount of energy to get something to
| the sun.
|
| Something in earth orbit is also orbiting the Sun. The
| Earth is traveling ~30km/second around the Sun. If you
| want to fall into the sun, you have to cancel out all
| that sideways speed.
| mumblemumble wrote:
| Another fun thing I didn't really understand all that
| clearly until I spent time playing KSP: Why it's
| theoretically easier to get to the Sun from Pluto than it
| is to do so from here.
| TeMPOraL wrote:
| Related: my mind was blown when I realize how easy it is
| to fall down to Earth (well, Kerbin) if you're in high
| enough orbit. I've had cases where my orbital velocity
| was on the order of 200 m/s, which means that at apoapsis
| you can just fart, and have the satellite crash into the
| ground a day later.
|
| (I've also had my fair share of high-orbit missions where
| in the middle of the launch I realized I'm aiming for a
| prograde orbit, where the contract specified retrograde.
| Instead of reloading game from launchpad, I just carried
| on, put my apoapsis at target altitude, and once reaching
| it, burned off couple hundred m/s of Dv to reverse the
| orbit's direction.)
| tomc1985 wrote:
| The point isn't really for it to fall into the sun, just
| to push it to some kind of orbit that is irrelevant to
| the space junk problem.
| rocqua wrote:
| Orbits are periodical. Anything you throw at the sun will
| come back up to the same height soon enough.
|
| (Ignoring smaller effects)
| sharpneli wrote:
| Another thing some KSP mods gave an impression to me was
| how seemingly magical ideal encounters and transfer
| windows they could make.
|
| Even though I couldn't make it myself by the usual orbit
| tools I also wouldn't be too surprised if it was possible
| to gather bunch of stuff with like < 100m/s delta v or
| whatnot.
|
| KSP taught me that flying a rocket is "easy". But
| calculating the stuff is hard (well, computationally
| intensive. So it can be easy, but hard for humans in
| their head).
| Robotbeat wrote:
| Yeah. I think KSP stock makes building rockets seem way
| too easy and docking way too hard.
| maccard wrote:
| I thought so too at first, but after a couple of (dozen)
| hours, I came to appreciate it. The rocket building
| leaves for incredible variety, it means as a beginner you
| can strap a few engines to a cockpit and get to the Mun,
| without having an understanding of why, while at the same
| time needing to actually plan and calculate delta for
| longer missions. Similarly the docking is fiddly and hard
| at first, but once you've done it a few times, it's a
| (mostly) rote exercise.
| TeMPOraL wrote:
| Agreed. It's good to learn and do it a few times, because
| it teaches you a lot about how objects in orbit behave in
| relation to each other.
|
| Docking itself has always been my favorite part, though I
| "cheat" by using a mod[0] that gives me a display[1] of
| relative velocities and orientations. My brain isn't
| designed to eyeball relative velocities from an outside-
| ship camera. But that's just the final part, applicable
| when you can literally see the target out of your window.
|
| Approach, now that's another story. Took me a while to
| learn how to match orbits without carefully planning a
| series of maneuvers. My new way is slightly less Dv-
| efficient, but much faster in terms of both in-game and
| wall clock time. I plot a "good enough" intercept (say
| within 5-50km separation, relative velocity doesn't
| matter, as long as it's less than my remaining Dv), and
| then as my ship is a couple dozen to couple hundreds
| kilometers from the target, I start doing small
| adjustment burns to minimize distance at flyby and
| relative speed. The goal is to eventually reduce flyby
| separation and relative speed at intercept to something
| reasonable (say, flyby at 100 m, 10 m/s relative speed).
| From there, I can just dock easily.
|
| It's not the way real docking happens today (though it's
| how it might in the future!), but I can execute a full
| intercept and docking in less than one orbit, which is
| more fun. Doubly fun to do this with transfers between
| celestial body - docking straight out of a transfer
| orbit, without first establishing a proper orbit around a
| moon/planet.
|
| EDIT: Triply fun with planetary landers, if you don't
| have enough Dv to reach orbit, much less to transfer to a
| station/orbiter module. You launch the lander into
| ballistic trajectory that intersects your target's orbit
| at its peak, and pray you time it right, so that the
| orbiter/station can decelerate and do a suborbital
| docking, and then boost back to safety. One mistake here,
| and you can lose both ships. God, I love this game.
|
| --
|
| [0] - Docking Port Alignment Indicator.
|
| [1] - https://i.imgur.com/J69AYEw.png. It looks trivial,
| but it packs enough information that you can easily dock
| looking only at that display. And something like this is
| what real astronauts would use, so it's actually making
| things more realistic :).
| mlyle wrote:
| > , maybe a collector craft could approach and collect
| several targets on a low Dv budget? It's not something
| you could do manually, but space has also this nice
| property that you can predict trajectories accurately far
| in advance,
|
| So, the issue is, in the low orbit environment there's no
| kinds of slingshot or other maneuvers available. You need
| to match height of the orbit at a point, and need to at
| least coarsely match velocity at that point, which means
| you're basically in the same orbit as the object. Sure,
| you can play games with slowly matching phase, etc, but
| the delta-v requirements are simply inherently high.
| baby wrote:
| Leo?
| filereaper wrote:
| Low Earth Orbit
|
| https://en.m.wikipedia.org/wiki/Low_Earth_orbit
| [deleted]
| Voloskaya wrote:
| It's fairly common nowadays. Companies like Nanoracks [1]
| specialize in this. Obviously this can only be done for
| cubesats.
|
| They are put into orbit simply by being ejected at the right
| angle and speed from the ISS.
|
| [1]: https://nanoracks.com/products/iss-deployment/
| filereaper wrote:
| Wow, this is super interesting.
|
| I didn't realize launching satellites had become so turnkey
| now where you don't have all the friction of dealing with
| NASA or any large space agency.
|
| Nanoracks has an interesting list of customers, like Adidas
| and Double-Tree by Hilton?!
| Rebelgecko wrote:
| Nanoracks does commercial things on the ISS other than
| cubesat launches. IIRC the Doubletree thing was they sent
| up an oven and had an astronaut bake cookies using their
| recipe
| GordonS wrote:
| Part of me is impressed by the economics of it (I had no
| idea such things were so affordable), and the rest of me
| is embarrassed by the almost flippant use of space
| tech...
| simonh wrote:
| I think Astronauts deserve the occasional freshly baked
| cookie too. Food preparation in space is arguably a
| serious business.
| nickik wrote:
| Checkout out: https://www.spacex.com/rideshare/
|
| Probably the cheapest way to launch things. However, SpaceX
| has no interest in dealing with everybody that wants to
| launch a cubsat so you have to go to an integrator.
| resist_futility wrote:
| Looks like they are launched from a specialty module on the ISS
| with only a spring https://iss.jaxa.jp/en/kiboexp/jssod/
| nickik wrote:
| Now its done with the Nanoracks Airlock:
|
| https://upload.wikimedia.org/wikipedia/commons/thumb/4/4c/Ex.
| ..
| tjpnz wrote:
| With Soichi Noguchi up there now this headline can be read
| literally.
| elliotec wrote:
| What? Can it not be read literally anyway? What's the context?
| T3RMINATED wrote:
| I dare Japan to hold USAs satellite. They spy on them DAILY.
| codezero wrote:
| The politics around a decision like this are fascinating. I
| assume they've already paid in part or in full for the launch,
| and regardless, they did R&D on a satellite which is itself an
| asset that is now difficult to return to the owner!
| jaywalk wrote:
| Also, "the contract with MAEU did not specify that the
| satellite cannot be used for military purposes."
|
| I completely understand why they're doing this, but it's tough
| to see how it's legal.
| bilbo0s wrote:
| Don't they say that the great secret of international law, is
| that there is no international law?
|
| This situation is an example of what they mean by that.
| WJW wrote:
| Concepts like legality have much less meaning between
| countries. It's not like there is a court where Myanmar can
| sue if it wants their satellite back. At this level, the
| ultimate recourse is declaring war and reclaiming it by force
| but we all know how that would turn out.
| adinb wrote:
| Isn't that what the World Trade Organization (WTO) is for?
| freeflight wrote:
| The WTO has been effectively out of order these past
| years as the US has blocked the appointment of new judges
| to the appeals court.
|
| It's supposed to have seven judges, a minimum of three
| judges are required to issue rulings, but since 2019
| there are only two judges left [0]
|
| So any ruling the WTO main body makes, like for example
| declaring US tariffs on China illegal [1], only needs to
| be appealed to be stuck in procedural limbo, which is
| exactly what ended up happening with the WTO ruling on US
| tariffs [2]
|
| [0] https://www.dw.com/en/wto-judge-blockage-could-prove-
| the-beg...
|
| [1] https://apnews.com/article/global-trade-china-
| archive-donald...
|
| [2]
| https://www.bloomberg.com/news/articles/2020-10-26/u-s-
| appea...
| adinb wrote:
| Thanks!
| celtain wrote:
| Not all international disagreements are disagreements
| between sovereign nations themselves. It's possible that
| MAEU could sue JAXA or Hokkaido University in a Japanese
| court if they think they're violating Japanese law.
|
| If that's not the case, or if the Diet passes a new law
| that protects their countrymen in this dispute, then yeah
| it becomes the type of conflict you describe.
| TameAntelope wrote:
| Diplomacy is a critical function of any government due to
| what you're saying, and IMO this could be a consequence of
| Myanmar neglecting that reality (for a myriad of valid and
| invalid reasons, I don't know enough about the current
| situation to speak with any intelligence about it).
| ramphastidae wrote:
| According to what law? Tried in which court? And enforced by
| who? International law is basically: "Don't like it? Well
| what ya gonna do about it?"
| DigiDigiorno wrote:
| Imagine you were contracted to release a satellite and then
| you realize you might be providing military equipment to a
| hostile nation.
|
| Would you really think to yourself "Well the contract doesn't
| say I can't do this"?...
| tkgally wrote:
| Also, the Japanese government and individual national
| universities, including Hokkaido University [1, in
| Japanese], have regulations on the export of technology
| that can be used for military purposes. I work at another
| national university in Japan, and there has been a lot of
| internal debate, with political overtones, about how
| strictly those regulations should be enforced and how to
| deal with technology that has both military and civilian
| applications. I can easily imagine the researchers at
| Hokkaido University deciding that the military coup in
| Myanmar meant that deploying the satellite would run the
| risk of violating the rules of either their own university
| or the Japanese government.
|
| [1] https://www.hokudai.ac.jp/research/export-control/
| rantwasp wrote:
| keep the satellite. shipping back is gonna be more than what we
| payed for it
| slg wrote:
| You used "they" a couple times in that comment and it is
| important to question who "they" is given the political
| environment in Myanmar. Is the "they" that paid for the
| satellite and did the R&D the same "they" that who would be
| controlling the satellite? If not, would the new "they" use the
| capabilities of this satellite in a nefarious way?
| seniorgarcia wrote:
| In context of this satellite, they is the MAEU (Myanmar
| Aerospace Engineering University) and the reason the
| satellite is being held is because apparently JAXA (Japan
| Aerospace Exploration Agency) can't reach the rector of the
| MAEU to make sure what the satellite would be used for.
|
| The reason why they can't reach the rector of the MAEU is
| because he might have been arrested or is in hiding
| (https://www.myanmar-now.org/en/news/soldiers-raid-
| aerospace-...).
|
| So, all in all, Japan is being careful and the situation in
| Myanmar is "undetermined". I think it is questionable where
| the "spying concern" is coming from, aside from being
| clickbait.
|
| >Officials at JAXA could not be reached for comment. MAEU did
| not respond to calls seeking comment, nor did a spokesman for
| Myanmar's junta.
|
| It could be used for spying, because it's a satellite with
| cameras. If it has the capabilities to be used for spying is
| unclear, all the data would go through Japan anyway. Japan
| does not want to comment on it, persons responsible at MAEU
| are in prison or in hiding and the junta would probably lie
| anyway.
| garmaine wrote:
| "Spying" looks like editorial click bait. It isn't even
| mentioned in the article. The concern I think is domestic
| use to commit genocide against their own people.
| simonh wrote:
| The article does mention concerns about military use. I
| think your being overly pedantic.
| garmaine wrote:
| Yes, use by the military to continue committing genocide
| against their own people. "Spying" in geopolitical
| context usually means use against other countries.
| seniorgarcia wrote:
| > "We won't get involved in anything that has to do with
| the military. The satellite was not designed for that,"
| one of the officials, a manager of the project, told
| Reuters, asking not to be identified.
|
| I dare you to find a quote by anyone familiar with the
| satellite citing military use.
| simonh wrote:
| He said it right there. If it has no possible military
| use, why did he even mention the military?
|
| Nice bit of goal post rearrangement there, given an
| explicit direct quote in the article stating the
| satellite could have military applications. On what basis
| do you assert that Human Rights Watch are not capable of
| assessing the satellites capabilities and possible uses?
| ehnto wrote:
| Maybe I am underestimating them, but I feel like the more
| likely scenario is a government and it's agencies in
| disarray. Would the new governing entity even know or care
| about that particular project right now?
| jopsen wrote:
| There is probably a propaganda win in launching a
| satellite.
| rusanu wrote:
| https://en.wikipedia.org/wiki/ENS_Gamal_Abdel_Nasser
|
| Mistral class helicopter carrier, payed by Russia, built in
| France, delivered to Egypt instead due to the War in Donbass.
| France had to compensate Russia.
| downrightmike wrote:
| Oppsie! We dropped it and it burned up. Sorry lol
| drak0n1c wrote:
| Something similar happened with the US and Iran. The Shah paid
| for military fighter jets, but then the Islamist theocracy took
| over. So the US froze the money and obviously wasn't going to
| deliver the jets to a USSR supported regime. The question of
| property legitimacy after a revolution is a recurring one
| throughout history.
|
| https://time.com/4441046/400-million-iran-hostage-history/
| selimthegrim wrote:
| Since when was Khomeini USSR supported? Tudeh and MeK got
| their butts handed to them pretty early on.
| drak0n1c wrote:
| In the beginnings and first few years the revolution was
| supported, but relations cooled by 1984.
|
| https://eng.globalaffairs.ru/articles/the-soviet-union-
| and-t...
| [deleted]
| eunos wrote:
| Should have just went with Russia and Chinese then.
| naringas wrote:
| "we can spy, but you can't" --"1st world" western powers
|
| There must be a more modern term than "1st world", I just don't
| know it.
| matheusmoreira wrote:
| FVEY. The Five Eyes. Five English-speaking countries that share
| military strength and intelligence. Somehow the world simply
| tolerates all the blatant espionage they perpetrate with zero
| diplomatic repercussions. The USA alone probably has more
| espionage satellites in space than every other nation combined.
| downrightmike wrote:
| USA learned it's lesson after being isolationist leading up
| to mass genocide and world wars. A league of nations didn't
| work, so things evolved into the USA being the guard dog for
| the world.
| xxpor wrote:
| Because other European countries know they're screwed without
| the US's backing. In return, those countries don't have to
| spend nearly as much on defense as they would otherwise. You
| can see why this would be politically advantageous for the
| Europeans.
|
| Outside of that, who could do anything diplomatically to the
| US that wouldn't just be laughed off?
| modo_mario wrote:
| You do realize the EU has a mutual protection clause
| similar to Nato. Russia can't exactly invade. It's economy
| is smaller than Italy's. I don't think the EU depends as
| much on US defence as some Americans would have one
| believe.
| colinmhayes wrote:
| Russia already invaded Ukraine.
| lucian1900 wrote:
| After the Ukrainian state was taken over by fascists in
| 2014 and started threatening ethnic Russians and Jews in
| the Donbass, a local referendum was held on whether to
| ask for help from the Russian Federation. After it was
| won, the help was provided.
|
| Like most history, it's a bit more complicated than it
| first appears.
| lolinder wrote:
| Ukraine isn't in the EU, so that doesn't actually prove
| anything about the EU's ability to defend itself.
| jsty wrote:
| > Somehow the world simply tolerates all the blatant
| espionage they perpetrate with zero diplomatic repercussions
|
| Because pretty much every other country with a security
| service is either pursuing similar operations or wants to be.
| Sure when something becomes public a fuss gets made, but
| oddly enough no concrete repercussions ever follow.
| simonh wrote:
| Having a military advantage confers no moral obligation to
| share it.
| dylan604 wrote:
| You can spy too any time you want, right after you develop a
| launch platform. Until then, you develop anything you want to
| deploy to space, but if the launch agency you've contract with
| changes their mind, well, you've got a nice shiny museum
| exhibit.
| naringas wrote:
| so... might makes right?
| samus wrote:
| Nobody is forbidding Myanmar to launch their own satellite.
| After all, the Chinese and the North Koreans pretty much do
| whatever they want up there as well. But if you cooperate
| with others to put something up there, it would be very
| unusual if you wouldn't have to compromise. This includes
| limits on what purposes the equipment can be used for.
|
| Actually, according to TA, it seems Myanmar's government
| hasn't quite decided what to do with the thing. It's
| probably quite low right now on their list of priorities.
| And the Japanese still have to consider whether to toss it
| out or not. After all, the thing is up there already (sunk
| cost fallacy and all that). It seems possible they can work
| something out.
| Rule35 wrote:
| Why are you discussing the _military_ of Myanmar if you don
| 't at some level agree (with xxpor below) that might solves
| conflicts even if it doesn't establish right.
|
| If you're so egalitarian as to ask the question, why not go
| all the way and ask why individual Myanmarese are't
| negotiating with the USA directly? You inherently privilege
| the Myanmar military while calling into question the
| legitimacy of the western democratic governments.
| xeromal wrote:
| Isn't that how the human race works? Big monke stronger
| than little monke
| xxpor wrote:
| Might might not make right, but it does make the winner of
| conflicts.
| adventured wrote:
| Since we're dealing with geopolitics, genocide, conflict,
| etc. - what does right have to do with anything? Other than
| being an entirely hopeless ideal that is discarded
| immediately in conflict between nations or peoples.
|
| Might dictating outcomes has always been a fact of life.
| Why would anyone attempt to deny that aspect of living in
| reality? What good does it do to pretend reality isn't what
| it is?
|
| Might determining outcomes between nations will never stop
| being true. Everything else - the UN for example - is
| merely a very small (often laughable) influence, and at
| best reduces the brunt of the might factor.
|
| Pick a major country at any point in history. Might is huge
| part of their equation and there are no exceptions.
|
| The US and China can freely ignore the world, freely ignore
| the UN, freely ignore all rules, international laws,
| anything they want to. That's because there is nobody that
| can do anything about it. That fact of how things actually
| work merely lessens as you scale downward with nations (as
| the nation in question gets weaker), it never goes away.
| Weak countries can pick on weak opponents, see: Armenia vs
| Azerbaijan. Might always ultimately determines the world,
| including in defeating Nazi Germany and the Empire of Japan
| in WW2. The strongest nations even have the most influence
| at the UN, so even soft politics is always backed by might.
| Rule35 wrote:
| Um yeah, I've got a gun and I'm not shooting you, but you - who
| have expressed displeasure with me - cannot get a gun because I
| believe you will shoot me.
|
| Harm to you: Not having a gun. Harm to me: death.
|
| Smart money is on maintaining a gap.
|
| How do you feel we should update '1st' world? Change '2nd' to
| refer to allies and vassals of China instead of Russia? Add
| '4th world' to indicate some other relation other than
| allies/enemies/unrelated?
| samus wrote:
| Why is any 1st world government supposed to help other
| governments spying? If Myanmar want a spy satellite up there,
| they should do it themselves. Or ask the Chinese. Can't imagine
| they wouldn't be interested in a launch platform closer to the
| equator...
| inetsee wrote:
| Can anybody tell me the resolution of the cameras on this
| satellite? Would it be better than the resolution of the images
| available from Google Maps? How much resolution is needed "to
| monitor agriculture and fisheries"?
| gattilorenz wrote:
| No idea, but it's not necessarily "regular" cameras. For
| monitoring agriculture, infrared imagery is often used due to
| the difference reflective properties of vegetation (and other
| stuff) at different wavelengths; having multiple type of
| pictures, at different wavelengths, is useful to get better
| estimates of what you're looking at than what you would achieve
| with just visible light.
| optimalsolver wrote:
| Not your satellite platform, not your satellite.
| rafale wrote:
| Not your keys, not your bitcoin :P
| dmos62 wrote:
| Finders keepers
| aaron695 wrote:
| > monitor agriculture and fisheries.
|
| Lol, are we going to bomb their corn fields next.
|
| Exactly how could it be used by the military?
|
| I don't know, but I feel like a satellite worth only $15 million
| and released from the space station wouldn't do much, but I might
| be pleasantly surprised tech has advanced enough.
|
| I don't get how on such a low orbit if would be useful to one
| country? I think it's called the MMSATS-1 (Lawkanat-1)
|
| https://www.global.hokudai.ac.jp/blog/collaborative-developm...
| simonh wrote:
| Cubes at imaging is really decent nowadays, this article shows
| images of a refugee camp.
|
| https://www.ft.com/content/c7e00344-111a-11e8-940e-08320fc2a...
|
| The concern is probably that satellite images could be used to
| identify and keep track of Rohingya and other ethnic minority
| settlements in jungle areas, and target them for attacks like
| the ones the military have been carrying out since 2017.
| aaron695 wrote:
| I think it's a stretch the possible cameras are good enough
| to use by the military.
|
| Here's photo's from Diwata-1 and Diwata-2 which is the same
| Japanese team and the Philippians. Similar costs, same
| project. https://www.goodnewspilipinas.com/diwata-1-2-view-
| from-space...
|
| Diwata-1/Diwata-2 have a High Precision Telescope (HPT) which
| I see no mention of on the MMSATS-1, only a super multi-color
| imager (SMI). But I can't see the exact specs.
|
| If you can find a photo of the underside of the MMSATS-1 you
| could see if it has a HTP by comparing it to this -
|
| https://directory.eoportal.org/web/eoportal/satellite-
| missio...
| simonh wrote:
| One of the express purposes of the satellite is to track
| agricultural activity, which by definition means it must be
| able to identify remote agricultural communities through
| e.g. forest clearance. That could be used to target ethnic
| minority settlements.
| aaron695 wrote:
| They have Google Maps. And normal paper maps. The
| Rohingya aren't some primitive natives who walk around a
| forest naked.
|
| Here's a (commercial grade) satellite of a before and
| after of one of the settlements being burned
| https://www.reuters.com/article/us-myanmar-rohingya-
| insight-...
|
| The rate of photos of the MMSATS-1 is low (if it has a
| HPT, I've seen no confirmation of this), and you can see
| from the photos you can't see a car. You can see the
| boats.
|
| If you want to look at the example of Diwata 1 leading to
| the detection of a disease in bananas, it's seems PR.
| Landsat-8 seems to play the greater role -
| https://confit.atlas.jp/guide/event-
| img/jpguagu2017/HTT21-05...
| simonh wrote:
| If Google maps and paper maps are good enough to track
| agriculture patters, why do they need a satellite at all?
| For a start Google maps images typically only update
| every 2 to 3 years. You're making no sense.
| st3ve445678 wrote:
| Begun, the space wars have.
| jtdev wrote:
| Maybe a "Spaceforce" is actually a good idea?
| TeMPOraL wrote:
| Sure it is. I love the show, can't wait for the second
| season.
|
| Oh, you mean that other Space Force? That I'm not sure of,
| but I hear it was just a much-needed reorganization of who
| does what in the US military.
| garmaine wrote:
| Pretty much everyone in the space industry is in agreement
| that Space Force is a good idea. We have been in agreement on
| this for decades, and it was a bipartisan project that
| started under Obama. Not our problem that Trump took the
| existing plan and lazily stamped his brand on it...
| yabones wrote:
| Nope, still not a good idea.
|
| The name alone suggests militarization of space which is a
| _horrible_ idea. The only thing that kept us alive through
| the 20th century was mutually assured destruction, and more
| importantly, the capability to detect ICBM launches and
| retaliate within the 30 minutes before your continent is
| glassed. Space launched nukes don 't give you any warning,
| you get at most 30 seconds to detect the shock heating in the
| high atmosphere before it's game over. It's an actual
| slippery slope, the very first payload containing weapons in
| orbit is a direct path towards space launched nuclear
| weapons.
| drusepth wrote:
| >Space launched nukes don't give you any warning
|
| Unless you have your own space-launched nukes and
| satellites?
| TeMPOraL wrote:
| While dangerous, it's not necessarily MAD-breaking. MAD
| stands on nuclear-armed submarines these days.
|
| Now, if someone figured out how to reliably detect
| submerged submarines from orbit, that would be truly MAD-
| breaking.
| selectodude wrote:
| There's nothing I wouldn't be willing to believe when it
| comes to the NRO.
| thevardanian wrote:
| The militarization of space is unfortunately inevitable.
| simonh wrote:
| Space to ground weapons are not really militarily
| practical. At any given moment only a tiny fraction of your
| weapons would be over a given target ready to strike. You
| have to wait for the other satellite to happen to over-fly
| the target area, which would generally only occur every few
| days at most due to orbital precession and earths rotation.
| PeterisP wrote:
| It's not like you drop nukes from above when you're above
| the target, like from an airplane, orbits don't work that
| way. You could fire the nukes on many missiles planned so
| that they would re-enter the atmosphere all at the same
| time for a surprise attack.
| simonh wrote:
| Sure, but you could only do so for a pre-planned attack
| at least several days in advance. That's not a very
| situationally flexible option, and if manoeuvring of the
| barrage to prepare the attack is detected, you're in big
| trouble. Their subs will pepper you with nukes long
| before your attack strikes home, and quite possibly well
| before you've completed the orbital adjustments of all
| your warheads.
|
| Another factor is that sub based missiles can launch from
| relatively close to their target and just skim out of the
| atmosphere, well below the orbits of even fairly short
| lifetime low orbiting satellites. That makes for quick
| trajectories. A satellite based weapon up there for
| extended periods would need to be in a relatively high
| altitude to avoid orbital decay. It turns out you don't
| actually get much advantage in terms of strike time even
| for a target that happens to be at an optimal position
| relative to your orbit.
|
| Finally, what do you do when the weapons reach the end of
| their service life? With terrestrial weapons they can be
| refurbished, upgraded or the expensive nuclear material
| recovered for remanufacturing. I know space weapons are
| sexy and cool, and I love me some Goldeneye style James
| Bond super-weapons, but they're not actually all that
| useful.
|
| It's one of the reasons the Star Wars missile defence
| project wasn't really viable as well. At any given time
| at least nine tenths of your defence satellites are over
| Australia, Africa, the Pacific, the Antarctic, or
| somewhere else peripheral rather than the Russia - USA
| theatre.
| __john wrote:
| I think it will be the thing he is most remembered for.
| downrightmike wrote:
| lol, M4s won't do any good. Just let JPL solve this.
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