[HN Gopher] A dwarf planet coming within 11 AU of the sun over t...
___________________________________________________________________
A dwarf planet coming within 11 AU of the sun over the next 10
years
Author : MKais
Score : 277 points
Date : 2021-06-20 18:39 UTC (4 hours ago)
(HTM) web link (groups.io)
(TXT) w3m dump (groups.io)
| ncmncm wrote:
| Cue, Avi Loeb insisting this is a follow-up to Uomuamua...
| jbverschoor wrote:
| Is that Nibiru?
| throwaway316943 wrote:
| Too small, maybe a generation ship on approach?
| optimalsolver wrote:
| We shall call it...Rama.
| pfdietz wrote:
| This is actually terrifying.
|
| That body is on a cometary orbit, and need not be stable long
| term. If it's chaotically pushed around by the major outer
| planets it might get sent into an orbit that gets into the inner
| solar system. And if something that size hit Earth, it would be
| game over for life here -- the impact would vaporize much or all
| of the oceans.
|
| Even an impact by something the size of comet Hale-Bopp would
| destroy all higher life on the planet.
|
| The chance of impacts like this may have been underestimated
| because of anthropic selection -- if any had occurred in the past
| (say) 1 billion years then we would not be here.
| mabbo wrote:
| It's expected orbit will take it around 54,600 AU from the Sun.
| The orbital period of something that far out is in the millions
| of years range.
|
| If it doesn't kill us this time, rest assured by the time it
| comes back we'll have done the job properly already.
| pfdietz wrote:
| I'm more referring to objects of this kind, not this specific
| object.
|
| Threats from supercomets are not a new concern:
| https://academic.oup.com/mnras/article/448/1/27/990672
|
| "A 100 km comet striking the Earth would carry ~1000 times
| the energy involved in the creation of the 150 km Chicxulub
| crater and would presumably remove the surface biosphere"
| perl4ever wrote:
| I think people have suggested the dinosaur killing asteroid
| may have caused global fires and rain of molten rock, so
| that scale might be sufficient as far as humans are
| concerned.
| grawprog wrote:
| I've always figured there's no point in worrying about giant
| planet destroying meteors, if one comes and we can't stop it,
| well we're all fucked. What can ya do at that point? If it
| can't be stopped and it can't be changed...well I guess we had
| a decent ride...at least it'll probably look cool before we're
| all vaporized.
| whatshisface wrote:
| What if it can be stopped in theory, but only if humanity
| pulls together and gets something right for once?
| EamonnMR wrote:
| An object that side won't be dissuaded with any of the
| firepower available to us. We'd be better off trying to
| build bunkers or something.
| grawprog wrote:
| Well, sure if it happens, i just meant in that whole
| inevitable no matter what doom scenario thing.
|
| I just mean, worrying about that or being scared is not
| really worth it. If it happens it happens. There's better
| things to dedicate that energy towards. Save the worrying
| about things like that for the people being paid to come up
| with solutions in the extremely rare chance this happens
| within any of ours, our children's or our grand children's
| lifetimes, after that I dunno, I'll probably be dead by
| then.
| dimator wrote:
| Then we're toast.
| Asraelite wrote:
| The post says "Incl. 95.46628 +/- 0.000052".
|
| Am I right to interpret this as meaning that the body has an
| extreme inclination, almost in polar orbit of the Sun? That would
| be pretty interesting; it would mean an orbit completely out of
| line with the rest of the Solar System.
| nwallin wrote:
| Yes.
|
| But it's not _that_ interesting or unusual. The Oort cloud
| doesn 't really obey the plane of the solar system the way the
| planets or Kuiper belt do. That's why it's called a 'cloud' and
| not a 'belt'.
| sam-2727 wrote:
| Certainly interesting, but not necessarily surprising. The Oort
| Cloud is roughly spherical so inclination would be expected to
| be isotropic overall. On average there will be less high
| inclination bodies (isotropic inclination has a pdf of sin(i))
| but they will still exist.
| [deleted]
| PicassoCTs wrote:
| Will this disturb longterm orbiting bodies (with exotic orbits)
| and drive them into the inner system, without the guardians able
| to catch?
| NegativeLatency wrote:
| I don't think so, to a meaningful extent. There's already lots
| of stuff out in the Oort Cloud with orbits out of the regular
| planar disk.
| mcorning wrote:
| For reference 1 AU (Astronomical Unit) is about 150 million km.
| Saturn ranges from being about 7 to 11 AU away from Earth.
| Voyager 1 is 152 AU away. This object is excitingly close and
| will be fun to study.
| chronogram wrote:
| How come our culture didn't base astronomical units around base
| 10 of our current units?
| detaro wrote:
| It's an old unit, so there wasn't a global standard yet, and
| it's exact value wasn't known for a long time, but it was
| still useful for ratios. E.g. if you observe the orbit time
| of another planet, you can tell its distance from the sun
| relative to the distance of Earth to Sun (1 astronomical
| unit) relatively accurately, even if you can't measure what
| it is in meters very well.
| Taek wrote:
| For my purposes 10 AU has a lot more meaning than 1 billion
| km. 1 AU has a lot more context
| [deleted]
| nitrogen wrote:
| Just because nobody has said it yet and it's often assumed
| knowledge, one AU is supposed to be roughly the distance from
| Earth to the sun.
| grawprog wrote:
| So pretty much between Saturn and Uranus....
|
| Even as an adult that still always makes me chuckle. I can't
| help it.
| edgyquant wrote:
| It's pronounced your-uh-ness by pretty much everyone (or
| your-ah-noose if your going by the greek god and not the
| Latin copy/paste.)
| [deleted]
| lopuhin wrote:
| I don't think Saturn comes that close, should be 8 AU at best,
| given that perihelion is at 9 AU.
| mcorning wrote:
| https://www.universetoday.com/15311/how-far-is-saturn-
| from-e...
|
| > For the sake of simplicity, Saturn is 1.2 billion km,
| roughly 7 AU, from the Earth when the two are at their
| closest approach to one another. They are 1.67 billion km,
| around 11 AU, from each other when they are at their most
| distant. Saturn and Earth are the closest to each other when
| they are on the same side of the Sun and at similar points in
| their orbits. The are the most distant when on opposite sides
| of the Sun.
| Denvercoder9 wrote:
| _> Saturn is 1.2 billion km, roughly 7 AU_
|
| That's a unit conversion error. 1.2 billion / 150 million
| is 8, not 7.
| jakeinspace wrote:
| I believe the 1.2B km was referencing mean orbital
| distance from the sun, which would be 8 AU, and therefore
| 7 AU from earth on closest approach.
| Denvercoder9 wrote:
| No.
|
| Saturn's perihelion (closest distance to the Sun) is
| 1.35B km (9.0 AU), its aphelion (furthest distance) is
| 1.51B km (10.1 AU), and its mean distance is 1.43B km
| (9.6 AU).
|
| Thus, at closest approach Saturn is 8 AU from Earth
| (since Earth orbits at an almost-constant 1 AU from the
| Sun).
| jakeinspace wrote:
| After checking Wikipedia, you are correct.
| [deleted]
| Fordec wrote:
| Is it possible to get a probe out that far in time to make a
| good intercept?
|
| I imagine with this (relatively) short notice this is cutting
| it a bit close to orchestrate a proper orbital insertion by a
| designed, manufactured and tested program?
| ernst_mulder wrote:
| Before I read that it is actually orbiting our star I briefly
| thought "maybe they had an accident with a nuclear waste dump on
| the far side of their planet"
| 34679 wrote:
| >almost undoubtedly the largest Oort Cloud object ever
| discovered- almost in dwarf planet territory!
|
| Not a dwarf planet.
| ptcrash wrote:
| Apologies if this is an obvious question but I'm not familiar
| with astronomy. Will this dwarf planet just pass through our
| solar system or is there a chance it will start to orbit our sun?
| clajiness wrote:
| > its orbit takes it from just beyond the orbit of Saturn (10.9
| AU) all the way out to the Oort Cloud
|
| It looks like it currently orbits the sun.
| perl4ever wrote:
| According to the link, the outgoing aphelion will be almost
| 40% more than the previous one, so I wouldn't assume it's
| going to orbit indefinitely.
| ptcrash wrote:
| Ah, for some reason I read the original message as some new
| dwarf planet was outside our solar system and had a
| trajectory towards it. Thanks for the clarification.
| MereInterest wrote:
| For the most part, conservation of energy dictates that bodies
| in orbit will stay in orbit, and bodies transiting the system
| will exit it. Think of it like a ball rolling down a hill, then
| back up a hill of equal height. By rolling downhill, it gains
| enough velocity to make it back up the hill.
|
| There are exceptions, of course. An asteroid passing through an
| atmosphere may be slowed down by friction (aerobraking), and be
| captured in orbit. Passing near another orbiting body, the
| interloper can be sped up or slowed down (gravity assist). But
| both of those require getting pretty close to a planet, and
| space is really big (citation needed), so it's unlikely that it
| would be captured.
|
| Edit: Looks like I had the same misinterpretation, that it was
| a rogue planet rather than an Oort/Kuiper belt object.
| ordu wrote:
| If it manage to do a gravity assist maneuver around some
| existing planet, it might. Probability of such is very low, I
| believe. Moreover, I think if there was any chance, scientists
| already knew about it. If they keep silence, then no, there are
| no chances.
| marcosdumay wrote:
| It is from our solar system. It has just a very eccentric
| orbit, but it was always orbiting the Sun.
|
| But for interstellar objects, the answer is always "no". Unless
| it passes very close to some object that there's an orbital
| slingshot (or a collision, the odds of both are basically
| zero), interstellar objects always move away.
| samus wrote:
| According to TA it _is_ orbiting the sun. The closest point out
| will be at beyond Saturn 's orbit, the farthest will be 30-50k
| AU. Of course, there are some error bars on these numbers that
| I can't interpret, and given that it orbits that far out, its
| orbit might actually be influenced by neighboring stars as
| well.
| nealabq wrote:
| For now they're calling it 2014 UN271. It's got a Wikipedia page:
| https://en.wikipedia.org/wiki/2014_UN271
|
| I suppose it'll get named soon.
| ceejayoz wrote:
| > could possibly reach magnitude 13 in early 2031
|
| Don't get too excited about looking at this one; that's a bit
| brighter than Pluto, so you'd need a pretty decent telescope to
| spot it.
| https://en.wikipedia.org/wiki/Magnitude_(astronomy)#Examples
| Sharlin wrote:
| I believe this is _absolute_ magnitude, and specifically,
| absolute magnitude as defined for comets [1]. At Saturn 's
| distance, definitely not a naked-eye object in any case.
|
| [1]
| https://en.wikipedia.org/wiki/Absolute_magnitude#Cometary_ma...
| perihelions wrote:
| Not in this case: the +13 figure is a predicted *apparent*
| magnitude. The absolute magnitude 'H' as your link defines is
| the 'H' field in the OP link, which is +7.8. (Note that's 'H'
| from your link's section on asteroid magnitudes, not comets
| or stars -- they're all on different scales).
|
| Here's the documentation for the fields in OP's data table:
|
| "H Absolute visual magnitude. A table converting H to a
| diameter is available."
|
| https://www.minorplanetcenter.net/iau/info/OrbElsExplanation.
| ..
| Sharlin wrote:
| Ah, thanks. So its _H_ _asteroid is currently +7.8, and
| if/when it develops a coma it should become a lot brighter,
| but unfortunately even at perihelion still way too faint
| for a naked eye.
| [deleted]
| pavel_lishin wrote:
| Aw, I thought this was going to be an extrasolar object, but it's
| an oort object orbiting the sun.
|
| It's also pretty small, about 1/20th the size of the moon. Huge
| for a comet, but smaller than Ceres.
| sam-2727 wrote:
| It can definitely feel not as cool from a popular science
| perspective but there are many unanswered questions about the
| Oort Cloud so study of this object would be scientifically
| invaluable, even if it doesn't yield any "pop-sci" results.
| Meerax wrote:
| Is this something we could plan and manage to launch an
| orbiter/lander to in time? Has anyone thought about the
| possibility of slapping something like a telescope on that and
| letting it beam back data and images from veryyyyy far out
| eventually?
| c3534l wrote:
| Apparently no one likes this idea. Here's mine: we nuke the
| planet and collect its smitherines for SCIENCE!
| 015a wrote:
| Let's send some boosters out there, redirect it to earth, and
| make a second moon. Come on people, what ever happened to
| doing shit cause its fuckin' rad, do you know how cool
| another moon would be?!
| f6v wrote:
| Let's just blow the moon up and give rise to 7 new
| genetically engineered races, man-fishes, and dwarves.
| beckingz wrote:
| If it worked in SevenEves I don't see why not?
| [deleted]
| hirundo wrote:
| Constructive interference from multiple tidal waves could
| flood huge coastal areas, killing or displacing millions.
| Uncool.
| jessriedel wrote:
| If you launch your telescope on a spacecraft and get it to
| match speed with the dwarf planet (which is necessary for a
| soft landing), there's not much point in actually attaching it
| to the dwarf planet. That just blocks the view of half the sky.
|
| Also, there will be nothing to see out there other than the
| dwarf planet itself.
| vmception wrote:
| and frozen aliens
| seaman1921 wrote:
| perhaps the sun's heat exposes them :)
| tonmoy wrote:
| Is that really true? If we manage to get a spacecraft get
| captured by the dwarf planet's gravity and orbit it, would
| that not be a lot less delta-V compared to if we made the
| spacecraft achieve the dwarf planet's orbit around the sun
| just by itself?
| jessriedel wrote:
| Yes, this is an aspect of orbital mechanics that people
| find unintuitive before they study it. You can't be
| captured by a planet's gravity alone. If you come in from
| infinity (i.e., not already captured) you will escape to
| infinity (remain not captured). The basic idea can be seen
| from the fact that gravitational dynamics are time-
| reversible, so if gravity could capture you like this you
| could also start in orbit around a planet and spontaneously
| be ejected.
|
| Now, something like this can work if you use an
| _irreversible_ interaction like aerobreaking, but this
| dwarf planet has negligible atmosphere. You could also use
| the dwarf planet for a gravitational assist (basically
| bouncing off it like a billiard ball), but I think
| gravitational assists from the other planets are almost
| always more convenient and effective.
| CamperBob2 wrote:
| That's pretty cool. It's wildly counterintuitive, but if
| it weren't the case, the planets would be orbited by lots
| of captured asteroids and debris, instead of/in addition
| to being covered in craters. The only explanation for why
| that doesn't happen is that it _can 't_ happen.
| shkkmo wrote:
| The presence of natural satellites indicates this can
| indeed happen. It just requires a pretty unlikely orbital
| configuration.
| dragonwriter wrote:
| > The presence of natural satellites indicates this can
| indeed happen
|
| No, it doesn't, because natural satellites are generally
| not captured, and for those that are captured, the
| process involves interactions with other bodies.
| perl4ever wrote:
| The first hit when I search "planets capturing moons"
| says natural satellites generally _are_ captured.
|
| "Most satellites of the outer solar system didn't form
| with their host planets"
|
| https://astronomy.com/news/2016/12/captured-moons-of-the-
| gia...
|
| Even Triton, which is the size of a planet and in an
| almost circular orbit, is thought to be captured, the
| last I heard.
| CamperBob2 wrote:
| No, it doesn't. No (rocky) planet has more satellites
| than craters, but every planet's gravitational field is
| larger than its surface.
| 8note wrote:
| Do we know how many of those craters used to be
| satellites?
| stickfigure wrote:
| Or an impact:
|
| https://en.wikipedia.org/wiki/Giant-impact_hypothesis
| [deleted]
| azernik wrote:
| It can _reduce_ the delta-V requirements, though - by the
| same principles as a gravity assist, a capture burn
| (especially into a loosely-bound planet-centric orbit)
| often takes less work than burning into the equivalent
| heliocentric orbit on your own.
| JumpCrisscross wrote:
| > _by the same principles as a gravity assist, a capture
| burn_
|
| Note to the audience: these mechanisms don't violate the
| conservation of energy because you aren't tapping the
| object's gravitational energy _per se_ but instead its
| orbital energy around the sun. Put another way, you can't
| do a gravity assist or capture burn in any direction.
| beckingz wrote:
| Right! The Oberth effect for a smaller body is not as
| large as it would be for earth, but would still be non-
| zero.
| jessriedel wrote:
| Ok, good point. Thanks.
| shkkmo wrote:
| > You can't be captured by a planet's gravity alone
|
| Technically, this isn't completely true. There are
| gravity assist techniques that will allow you to dump
| speed by essentially adding your momentum to the object
| you are trying to orbit. The is basically an anti-
| slingshot manuever.
|
| In practice, I believe the range of scenarios when this
| is possible with a dwarf planet is so small as to be
| practically useless.
| tmhrtly wrote:
| What if we crash landed into it? That would probably tick
| the irreversible box. Clearly engineering difficulties
| quite high though!
| ehsanu1 wrote:
| It's a cool idea, but seems super sci-fi. Might need some
| wonder materials to make it feasible, even then that
| would be a really big crumple zone. Or flubber. Another
| crazy idea: latch on to the planet from the side, like a
| skateboarder hitching a ride by hanging on to a truck.
| Again, wonder materials required.
| azernik wrote:
| NASA and the Soviets didn't need any wonder materials,
| just airbags. (Though they did a lot of braking first -
| either with the atmosphere for NASA at Mars, or with
| thrusters for the Soviets at the Moon.)
| Sharlin wrote:
| This is often jocularly called _lithobraking_ and is
| typically not advisable.
| fouronnes3 wrote:
| > not advisable
|
| Unless you're NASA landing a probe on Mars in 1997.
| Sharlin wrote:
| Seriously, the tandem failures of the Mars Polar Lander
| and Mars Climate Observer missions were probably
| something NASA as an organization needed at the time. A
| reminder that Space Is Hard, and you can only pick two of
| "faster", "better", and "cheaper". Since then, NASA's
| Mars program has grown in both scope and ambition, yet
| remarkably has had zero loss-of-mission failures during
| that whole time!
| fouronnes3 wrote:
| I was referring to the successful landing of Pathfinder
| but yeah... Space is Hard and NASA is good at it are both
| very true.
| garmaine wrote:
| Most of the velocity of Pathfinder was shed using
| aerobraking and parachutes. The crash-balloon landing
| system just shed the last tiny sliver of velocity after
| cutting the chutes.
| isoprophlex wrote:
| It's a dwarf planet of ~ 200 km diameter. The thing has a
| miniscule gravity well, it won't matter much compared to
| launching from earth and matching orbits with it, i
| think...
| azernik wrote:
| For comparison, that's about 10% of the Moon's diameter,
| i.e. 0.1% of its volume. (The mass ratios are probably
| within that 0.1% ballpark, but can't tell for sure until
| we know more about its composition.)
| anfilt wrote:
| Like till it gets closer we dont even know if it would be
| suitable to put something like that on it.
|
| Although it does seem like interesting idea.
|
| However, we have sent probes much further than this object (aka
| the voyager missions).
|
| So it would mainly be useful for studying this object. So a
| telescope would be less than ideal since we could always in
| theory deploy a telescope much deeper into space if we wanted.
| floatrock wrote:
| Interestingly, the voyager missions were also timed-events --
| they were launched when they were because JPL realized it was
| a 1-in-175-year alignment of the outer planets that made it
| feasible to launch just a few crafts to visit the outer
| planets all in one go:
| https://en.wikipedia.org/wiki/Grand_Tour_program
| f6v wrote:
| AFAIK many launches are timed to make the flight shorter.
| Although not on 1 in 175 years, but shorter windows.
| bewaretheirs wrote:
| Just launch a deep-space telescope; it would be easier.
|
| Soft-landing the telescope on an airless body would be harder
| (in delta-V terms) than just launching it into an equivalent
| solar orbit. And the body would block about half your view of
| the sky at any one time.
| jbay808 wrote:
| Could you get a nice gravity boost away from the sun by just
| following it for as long as possible?
| _Microft wrote:
| The easiest way to think about this is as perfectly elastic
| collision between the spacecraft and the planet (mediated
| by gravity, but this is an unnecessary detail already).
| jstanley wrote:
| I think the point is that in order to follow it, you need
| to (at some point in time) be at the same place and with
| the same velocity. Then you'll follow it.
|
| But the energy required to do that is almost the same as
| what it would be if the dwarf planet wasn't there. You
| could get onto exactly the same orbit for roughly the same
| amount of energy, and if you relax the requirement that
| there be a dwarf planet nearby, you can choose superior
| orbits.
| lamontcg wrote:
| No, that's not how gravity boosts work. If you match speeds
| with an object you actually get zero boost.
|
| The point of a gravity boost is to come in pretty hot
| (relative to the body you're boosting off of) and then go
| out pretty hot in a different direction. So you take your
| relative velocity vector at the point of the encounter and
| twist it around. By doing that you change your orbital
| energy around your central body (the sun) by a lot, and the
| other object will lose a similar amount to keep the
| bookkeeping equal.
|
| If you have zero relative velocity compared to the thing
| you want a gravity assist off of you can't get an assist.
| It isn't like drafting a semi.
| 0-_-0 wrote:
| I think it should provide a much stronger slingshot
| velocity boost than any other planet, however getting to
| 11AU first is not easy.
|
| https://en.wikipedia.org/wiki/Gravity_assist
| btilly wrote:
| For the best gravity assist you want to have a large
| delta V, and you want to come in on a hyperbolic orbit
| that causes you to turn by 90 degrees.
|
| This object has all of the delta V that you could want,
| but for an object of that mass, the hyperbolic orbit
| would require going through the planetoid which you can't
| do. And if it was dense enough that you could (for
| example a miniature black hole), the tidal forces during
| the turn would be insane.
|
| So no, this object cannot give a decent slingshot.
| simonh wrote:
| The magnitude of the slingshot boost increases with the
| mass of the planetary body. This thing is smaller than
| any of the planets so you'd get a much smaller boost. The
| best planet for slingshotting from is Jupiter because
| it's the most massive.
| z3t4 wrote:
| Too far out from the sun and it wouldn't be able to re-charge
| using solar panels. Could put some kind of nuclear power plant
| on it though. And as others has pointed out, you would need to
| match the speed, so you could just as well use that power plus
| gravity assists to get far out. Landing on such a body would be
| really interesting though.
| ianai wrote:
| Probably the reason to orbit such a planet would be to help
| comms from a ground station on it.
|
| 11 AU though seems like quite the stretch right now but maybe
| if there were a fleet of Spacex Starships in operation...
| PaulHoule wrote:
| I think it is not so exceptional, it is just this is one of the
| first ones we spotted.
|
| Practically "outer solar system objects" and "interstellar
| objects" are overlapping categories since there is transport
| between the two.
| MKais wrote:
| How fast can we build and launch something to rendezvous with
| this dwarf planet?
| jessriedel wrote:
| New Horizons took a nearly straight shot to Pluto (just
| stopping by Jupiter on the way for a gravity assist). That trip
| took 9 years to travel 40 AU (not at constant speed, of
| courses, since it's constantly being drawn toward the Sun).
| This dwarf planet makes its closest approach at 10 AU, so you
| could do a fly by in less than 3 years if you wanted to pay for
| it. However, the science return from a flyby would be limited
| compared to falling into orbit around it.
|
| Rosetta took 10 years to match pace with and orbit a comet
| (which had a closest approach to the Sun less than 1 AU) using
| a number of gravity assists.
|
| https://raminskibba.net/2014/08/17/rosetta-and-the-comet/amp...
|
| https://raminskibba.files.wordpress.com/2014/08/f4-large.jpg...
| messe wrote:
| Getting into orbit would be rather difficult, as the probe
| would have have to match the planets velocity at perihelion.
| My instinct says it's probably just on the edge of doable
| (although I'm not sure on which side), but I haven't crunched
| the numbers. It would almost certainly need to be launched on
| a Delta-IV or Falcon Heavy class vehicle.
|
| EDIT: s/perigee/perihelion. I could say periapse and be
| neutral, but perihelion sounds cool.
| jessriedel wrote:
| The speed of Rosetta's comet at perigee is, I think,
| significantly grater than the max speed of this dwarf
| planet. The dwarf planet has a much higher apogee, of
| course, but escape velocity, corresponding to infinite
| apogee, is finite and not that large, and Rosetta had to go
| much deeper into the Sun's gravity well. So, as a non-
| expert who hasn't done the numbers, I'd guess matching pace
| with the dwarf planet would be easier (requiring less delta
| V and/or gravity assists) than Rosetta with the comet.
| messe wrote:
| Somewhat unintuitively, thanks to the Oberth effect, it
| can be easier to reach escape velocity closer to an
| object, (Humorously portrayed in https://xkcd.com/1242).
|
| Aside: if you are looking to learn more, I cannot
| recommend Kerbal Space Program enough.
| perl4ever wrote:
| I've been aware of people talking about Kerbal Space
| Program for years and years, but I lost interest in
| playing it when I heard it didn't do real N-body
| gravitational calculations because they were too
| intensive.
|
| I still find that inexplicable. To me, it sounds like
| saying "our calculator only does basic arithmetic on four
| core machines, square roots are too slow".
| messe wrote:
| Not really that inexplicable, it's a video game. It's not
| for computational reasons, but to make gameplay easier to
| reason about; because again, it's a video game.
|
| The mechanics are simplified, yes, but patched conics is
| quite a good approximation for many cases, and great for
| developing an intuition for the basics.
|
| There is a mod that includes n-body calculations called
| Principia if you're interested in that.
| thoughtsimple wrote:
| I think you meant: https://xkcd.com/1244/
| messe wrote:
| Whoops. Yep, that's the one.
|
| Maybe I'll be vindicated when it turns out the planetoid
| is made out of grey goo.
| perihelions wrote:
| It's difficult to believe that ten years from now, there'd
| be any serious options other than Starship and its future
| peers. (Incidentally, the Delta IV is already at end-of-
| life; ULA is replacing it with Vulcan and its Blue Origin
| engines. The final Delta IV-H launches are planned for
| 2023).
|
| https://spacenews.com/ulas-delta-4-heavy-down-to-final-
| five-...
| messe wrote:
| I more meant that it would take at least that size-class
| of heavy lift launch vehicle.
|
| With Starship this would definitely be doable, and I'm
| really optimistic about it; I just wanted to be cautious
| in my predictions.
|
| I also wouldn't be surprised if Delta IV's life gets
| extended. Vulcan is facing plenty of development delays,
| and Blue Origin are yet to produce anything useful.
| ramraj07 wrote:
| Might there be not some benefits to try to get into orbit
| around this object, like perhaps a free ride to the Oort
| Cloud maybe?
| jfengel wrote:
| There's no such thing as a free ride. If you can soft
| land on it you're already going to the Oort cloud.
|
| You could get a free ride by having it crash into you,
| but that's going to be like catching a bus by letting it
| hit you, at ten thousand miles an hour.
| perl4ever wrote:
| In a few years, can't we look forward to SpaceX making it
| routine to refuel in orbit? If we assume that's feasible, I
| wonder what sort of missions it would enable, other than
| human spaceflight.
| throwaway316943 wrote:
| Maybe starship will be ready with orbital refueling in time
| to make a faster trip. Imagine being able to do a sample
| return mission from such an object.
| orliesaurus wrote:
| I wonder how/IF this will cause anything to spike solar flares?
| that's what's scary to me - all it takes is one big burst and bye
| bye to our tech....
| ceejayoz wrote:
| A dwarf planet wandering around Saturn's orbit isn't gonna do
| very much to the Sun.
| _Microft wrote:
| No, no need to worry. Coronal mass ejections causing
| geomagnetic storms are really something to worry about but this
| thing is just a piece of rock flying around the Sun at very far
| distances (from our point of view). It is coming no closer than
| eleven astronomical units to Sun (1 AU is the mean distance of
| Earth to Sun).
| orliesaurus wrote:
| Yeah I totally misunderstood the distances - my bad.
| _Microft wrote:
| There is a website that visualizes the distances in the
| solar system at the scale of _1 pixel to the diameter of
| Moon_. In the lower right corner there is a symbol with a
| "C" and some lines around it that makes you automatically
| travel at the speed of light. Start the journey, put it on
| an extra screen if you have one and see _nothing_ happen
| for most of the time ;)
|
| The current distance from Sun is shown in the bottom center
| and you can change units in the menu attached to it.
| "Astronomical units" or "light minutes" might be the most
| useful, kilometers or miles if you just want to be blown
| away by the order of magnitude.
|
| https://joshworth.com/dev/pixelspace/pixelspace_solarsystem
| ....
|
| I also submitted it for discussion here:
|
| https://news.ycombinator.com/item?id=27573172
|
| Edit: fixed the scale, it's 1px:diameter of Moon, not
| 1px:distance Earth-Moon as I initially wrote.
| messe wrote:
| I'm not seeing the relation other than it's also in space (so
| is the earth and everything on it by the way).
|
| Why would this do anything to spike solar flares? It's a lump
| of rock and ice 130km across, further out than Saturn. What
| possible mechanism do you think there is that would cause that
| to occur?
| orliesaurus wrote:
| @messe guess you're right - I'll take the downvotes...
| thechao wrote:
| You voiced your comment as more speculative rather than as
| a question. Please don't stop asking questions!
| orliesaurus wrote:
| Ty!
| DaiPlusPlus wrote:
| > It's a lump of rock and ice 130km across
|
| That's it? I was hoping for something at least the size of
| Texas...
| messe wrote:
| It's almost certainly bigger than an olympic swimming pool,
| and definitely larger than an American football field.
| hownottowrite wrote:
| It won't do anything.
|
| Also, Carrington class events are very rare. You should worry
| more about space junk crashing into important things and even
| then it's not much of a worry.
|
| https://warwick.ac.uk/newsandevents/pressreleases/likelihood...
| EarthLaunch wrote:
| > The analysis shows that 'severe' magnetic storms occurred
| in 42 out of the last 150 years, and 'great' super-storms
| occurred in 6 years out of 150
|
| That seems extremely imminent, like in my lifetime. How many
| of these events would shut down tech for months or years? Are
| those odds worth risking civilization over?
| 8note wrote:
| As far as space weather goes, I remember the forecast being
| severe all through September while I was doing magnetic
| surveying in northern Sask.
|
| Sever might not be so dangerous
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