[HN Gopher] Rocket Carrying North Korean Spy Satellite Crashes i...
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Rocket Carrying North Korean Spy Satellite Crashes into Sea
Author : nickthegreek
Score : 87 points
Date : 2023-05-31 16:39 UTC (6 hours ago)
(HTM) web link (gizmodo.com)
(TXT) w3m dump (gizmodo.com)
| jerkstate wrote:
| I've seen a lot of reporting, including this, which states that
| this is North Korea's "first" spy satellite. I thought it was
| well known that NK has performed at least 2 successful satellite
| launches previously, KMS-3-2 and KMS-4, which are documented on
| Wikipedia and tracked on n2yo.com. Does anybody understand the
| disconnect between the reporting and the evidence of 2 existing
| spy satellites?
| zamadatix wrote:
| Officially, those were non-spy Earth observation satellites.
| Not that that means much, but this one is actually labeled a
| spy satellite. Besides that, KMS-3-2 is known to have gotten to
| orbit while failing to stabilize and KMS-4 is not known to have
| sent any signals back.
| jerkstate wrote:
| Good points, according to the Wiki page, KMS-4 was initially
| tumbling and then shown to have stabilized, which seems to
| indicate that communication was established.
| zamadatix wrote:
| Not necessarily, at least in terms of communications back
| https://space.skyrocket.de/doc_sdat/kwangmyongsong-4.htm.
| Of course, it's also possible nobody has publicly tried
| looking at the right time. At the same time, it's also
| possible it wasn't really a functioning imaging satellite
| in the first place and was more just another test. Hard to
| tell when the official source just says whatever sounds
| most interesting that day.
| AYBABTME wrote:
| Fun fact: a wartime-like siren rang in Seoul for 1min, freaking
| out everybody, until it was announced that it was a false alert.
|
| (I wasn't there but I saw people panicking on Kakao Talk group
| chats)
| boeingUH60 wrote:
| [flagged]
| kjs3 wrote:
| Since they've done it successfully before[1][2][3], in addition
| to that whole working nuclear device thing, why wouldn't we?
|
| [1] https://www.n2yo.com/satellite/?s=39026 [2]
| https://www.n2yo.com/satellite/?s=41332 [3]
| https://en.wikipedia.org/wiki/Kwangmy%C5%8Fngs%C5%8Fng-4
| boeingUH60 wrote:
| Ah, I stand corrected!
| mabbo wrote:
| I keep telling people: Space is _hard_.
|
| > The rocket lost thrust after the first stage separation due to
| an "abnormal startup of the engine" on the vehicle's second stage
| that may have been caused by an instability in the engine and
| fuel system, according to KCNA.
|
| This is the challenge for most newcomers to space deal with.
| Every space startup in the US over the last couple years seems to
| have all had some trouble between stage 1 engine cut off and
| stage 2 operating. It's so easy in Kerbal Space Program!
|
| You need to: Stop your main engine; disconnect the first and
| second stage cleanly, successfully; put at least a little
| distance between first and second stage; _Start the stage 2
| engine_ in a vacuum and in freefall (which you cannot test out on
| the ground) and do it remotely /autonomously; have stage 2
| correctly identify its own position and speed well enough to aim
| to the stable orbit you hoped for.
|
| Oh, and don't forget to successfully ditch your faring at some
| point or the satellite is trapped in an egg shell with no solar
| panels, communications equipment, or (in the case of a spy
| satellite) telescopes.
| systems_glitch wrote:
| It was hard enough with two Estes engines! Often that second
| stage went off into the wild blue, never to be seen again, at
| some weird angle, or even spinning!
| vidanay wrote:
| LOL. Me and my friends designed a two stage rocket, and of
| course we insisted that our first attempt use "D" size
| engines. The first stage took the rocket up about 75-100 ft
| and when the second stage lit off, the rocket somehow kicked
| over and was flying perfectly horizontal.
|
| The problem was, we were launching from the bottom of a
| retention basin at the local park district so we started out
| at -40 ft altitude. This meant the rocket went zooming across
| the neighborhood only slightly above tree top level.
| chasd00 wrote:
| in the high power rocketry the newer flight controllers
| that have staging capabilities have lockouts now. We can
| configure logic like "only fire the second stage igniter if
| N seconds have elapsed since stage 1 burnout AND the rocket
| is traveling at a min of X ft/sec AND no more than Y
| degrees off vertical". It makes things a lot safer and more
| convenient
|
| 1) an M motor igniting 45 degrees off vertical 20k feet up
| means a long drive let alone a long walk.
|
| 2) an M motor igniting at a negative velocity ( descending
| and likely pointing down) is very scary heh.
| polishdude20 wrote:
| A year back or so I built a thrust vectored model rocket
| with two stages using an Estes E12 and an F15 motor for
| the second stage. The flight computer had logic in it to
| only light the second stage if the first stage had been
| successful to lift off the ground and the rocket at some
| vertical angle plus/minus some degrees and the velocity
| was positive upwards and non-zero. Luckily this first
| attempt worked out!
|
| https://www.youtube.com/watch?v=zPtFv-cwcfQ
|
| The first stage was designed to be pushed out by the
| second stage and a bit before the first stage was
| completely out or the rocket would lose too much control
| authority.
| vidanay wrote:
| We had Christmas paper tubes, balsa fins cut with a dull
| xacto knife, a hand carved nose cone and a super glued
| washer as a thrust ring.
| systems_glitch wrote:
| That sounds about right :P There's some really cool stuff
| nowadays, but I certainly didn't grow up with it!
| foobarbecue wrote:
| So YOU were the ones that started that fire in October Sky
| vidanay wrote:
| Well, my grandfathers surname was Hickman, and I was born
| in WV.
|
| (I know, Homer Hickam is different...but it's close)
| weard_beard wrote:
| Same latin root
| systems_glitch wrote:
| Met him once in college, I was in the Corps of Cadets at
| Virginia Tech, which is where Homer Hickam ended up as
| well. Very humble guy, at least in the few minutes I was
| around him.
|
| Fun fact, while at VT he led the creation of the original
| Skipper cannon. He and a bunch of other cadets thought it
| was shameful that VT had no cannon and VMI would trot out
| this little deck gun ("it was really more like a mortar!"
| according to him) at football games and shoot it off. He
| amassed a bunch of brass uniform bits and approached a
| foundry in IIRC Radford about it. They laughed about how
| a cannon made of uniform brass would blow up, but traded
| them for gunmetal brass.
|
| The first time they fired it was a salute for President
| Kennedy, but the assassination happened before they had
| time to drill a touch hole. They rounded up every ketchup
| squeeze bottle they could find, put the charge of powder
| in that, and taped a piece of fuse in the spout. The
| ketchup bottle assemblies were lit and slid down the
| barrel.
|
| Years later, a bunch of drunk cadets on Skipper Crew blew
| the original up. They kept cramming charges down after
| misfires, I think they had three in there when it went.
| The explosion blew up the caisson and threw shrapel, some
| of which embedded in Slusher Tower and is supposedly
| still there. The pieces were gathered up, mostly
| reassembled, and at least when I was there resided in the
| Corps Museum.
|
| Anyway, yeah, rockets!
| vidanay wrote:
| My favorite Hickam story is the ultimate "Do you know who
| I am?"
|
| "And I am on the National Space Council that oversees
| NASA,"
|
| https://www.usatoday.com/story/news/nation-
| now/2018/08/22/na...
| systems_glitch wrote:
| Nah I grew up in a different part of southern WV...and a
| few decades too late to be responsible!
| yabones wrote:
| Well, if your goal was to create an anti-ship cruise
| missile, I'd say you're about half-way there..!
|
| https://en.wikipedia.org/wiki/File:Brahmos_ER.webm
| Arrath wrote:
| Oh that is just brilliant. Model rocket shenanigans were a
| highlight of my childhood.
|
| Turns out, duct taping extra motors onto the rocket body as
| a cluster of second stage engines, initiated by cannon fuse
| itself ignited by the first stage didn't work so hot.
| WWLink wrote:
| I had a few model rockets, but I also made some
| completely custom ones out of index cards wrapped around
| a small motor. I added curved fins so one would spin.
| THAT was interesting! One of my (normal estes) rockets
| was hanging from a tree over a bike path by the park for
| like a week until I finally brought a ladder and some
| poles to get it down. Honestly I'm surprised nobody ever
| tried to grab it lol.
|
| Edit: The very first estes rocket was from a kit - our
| teacher had a "rocket week" and we all made and launched
| rockets. Mine went up, a fin fell off, then it u-turned,
| and then went straight for the math teacher.
| sidewndr46 wrote:
| I believe you can start the second engine without stopping the
| first engine, then initiate separation and cut fuel to the
| first stage engines. A number of rockets feature this design
| and have a way for the rocket exhaust gas to pass to the
| outside of the hull before separation occurs.
| kjs3 wrote:
| The old Soviet Vostok did something similar with the third
| stage, AFAIK.
| m4rtink wrote:
| Yep, its called hot staging & was used on some of the Titans
| for example.
|
| Another even more conservative option is to ground start all
| your engines and then throw some of them away directly
| (original Atlas) or with a stage (R7/Soyuz).
|
| There are certainly some tradeoffs with this, such as making
| it impossible to use a proper altitude/vacuum optimized
| nozzle if all your engines are ground started.
| ericbarrett wrote:
| In this vein, I highly recommend the RP-1 mod set for KSP1,
| which introduces (among other things) ullage and engine start
| failures, launching from a realistic Earth. Really gave me a
| huge appreciation for the difficulty of achieving orbit.
|
| https://github.com/KSP-RO/RP-0
| teeray wrote:
| Never mind the whole magic trick of landing the first stage on
| a barge and catching the faring in a big net.
| notfish wrote:
| They actually just scoop em out of the ocean instead of
| catching the fairings now
| sidewndr46 wrote:
| The recovery of the shuttles SRBs was always really cool to
| me. They float and the process even included manipulating
| their buoyancy to get them upright for easier recovery!
| gabereiser wrote:
| M/V FreedomStar and M/V LibertyStar were the recovery
| vessels. I named my sailboat the S/V FreedomStar in
| namesake. Out of Cape Canaveral, FL.
| LegitShady wrote:
| some people think the goal of kerbel space program is to launch
| rockets into space ... i think its to have them fail in
| hilarious fashion. we are not the same.
| [deleted]
| geocrasher wrote:
| Even before the rocket crashed into the sea, its launch was
| deemed controversial due to an international ban on North Korea
| from using ballistic missile technology
|
| The takeaway from this is that the international community is
| concerned that N Korea is developing ballistic missile technology
| under the guise of an orbital vehicle. The difference between
| orbit and sub-orbital flight is only a bit of Delta V and
| different payload.
| jzawodn wrote:
| You used the word "only" there to imply ... well, that it's
| simple? I don't think most serious aerospace folks would agree
| with that assessment.
| Thrymr wrote:
| Well, sure, it's not that simple, but the main point here is
| that it's "easier" to hit any point on the surface of the
| Earth with a rocket than it is to get a payload into orbit.
| geocrasher wrote:
| Nothing is _simple_ in aerospace, and I 'm sure there are
| things I'm missing. But generally speaking, an orbital
| vehicle becomes suborbital when it doesn't have enough speed
| to not fall back to the Earth. There's re-entry to contend
| with, but that's a solvable issue. And then there's the
| payload, also solvable.
| giantrobot wrote:
| The word "only" is appropriate here. If you _have_ an ICBM it
| 's still a challenge to get to orbit. If you _have_ a rocket
| capable of getting to orbit you automatically have an ICBM.
| If you 've got the power to get to orbit you've got the power
| for a ballistic trajectory.
| m4rtink wrote:
| Or possibly to build a FOBS (or even put nukes in orbit
| outright).
| HarryHirsch wrote:
| The bigger challenge is to get _out of orbit_ into one
| piece. Heat shields for the transonic regime are not
| trivial technology.
| tomcam wrote:
| > The rocket lost thrust
|
| At my age I completely understand that issue
| jmkni wrote:
| I'm amazed they admitted it! Not even claiming it was 'shot down'
| or denying completely that there ever was a spy satellite, just
| straight up admitting that it didn't work.
| Beached wrote:
| for internal drpk propaganda, it would be fairly difficult to
| keep the launch failure from the public, when success is orbit.
|
| the best spin on a failure is partial success. to their
| population, dprk has one job, to protect the population from
| the imperialists. losing the rocket to military action which
| they have been claiming they have successfully been keeping at
| Bay is a worse internal spin than 2nd stage failure
| AnimalMuppet wrote:
| What's it doing crashing off of the _west_ coast of Korea? If you
| 're trying for orbit, don't you usually launch east, so that you
| get a boost from earth's rotation? Or did the rocket just
| malfunction that badly? (Or is the article just wrong on that
| detail? Or did I read it wrong?)
| kryptiskt wrote:
| Spy satellites are launched to highly inclined orbits (think
| passing over the poles) so they can cover the whole of the
| Earth and slightly against the Earth's rotation so they can be
| sun-synchronous[0]. So this is just what you would expect from
| such a satellite.
|
| [0] https://en.wikipedia.org/wiki/Sun-synchronous_orbit
| Alupis wrote:
| A guess would be to avoid Japanese airspace, who promised to
| shoot down anything flying overhead. That assumes this rocket
| was actually intended to reach orbit and deposit a real
| satellite.
|
| It seems very ambitious to try to park a satellite in orbit on
| your very first orbital rocket. Unless I'm missing something?
| BWStearns wrote:
| They've gotten a couple sats to orbit.
| https://en.wikipedia.org/wiki/Unha
| ancientworldnow wrote:
| They put their first satellite in orbit in 2012 confirmed by
| NORAD. This is not the first launch of a satellite, only a
| "spy satellite."
|
| Honestly, feels like a concerted media effort to stoke panic
| about North Korea. Japan and South Korea acted like they
| didn't know was happening publicly (alarms etc) despite being
| informed of the launch publicly days before as reported in
| the media.
| AnimalMuppet wrote:
| > Japan and South Korea acted like they didn't know was
| happening publicly (alarms etc) despite being informed of
| the launch publicly days before as reported in the media.
|
| They may have known it was _happening_ , but once the
| launch malfunctioned, they didn't know where it was
| _going_.
| bink wrote:
| And I don't think either side trusts the other when they
| say "we're launching a rocket near you but not at you".
| bonestamp2 wrote:
| Not to mention, they have to trust that they're actually
| telling the truth because it's basically an ICBM with a
| satellite as a payload (instead of an explosive weapon).
| Heck, it could still be both. Since it's a hostile party
| launching it, they have to treat it as if it's a weapon
| before it even launches (such as warning they'll shoot it
| down if it's in their airspace).
| Rebelgecko wrote:
| For some high inclination orbits (like if you want a polar
| orbit that covers the whole world) it might make sense to
| launch in a NNW or SSW direction. Even for lower inclinations,
| sometimes it's easier for geopolitical reasons. IIRC Israel
| always launches retrograde over the sea to avoid upsetting
| their neighbors, could be similar with NK
| oh_sigh wrote:
| Their launch complex is in the far west of the country, and
| directly east does cross over portions of Korea Bay(/Yellow
| Sea). Or, I guess, they could have been going for a polar
| orbit.
|
| 39.65974870373334, 124.70613853508173
| wkat4242 wrote:
| It was launched from Tonghae which is in the east right?
| oh_sigh wrote:
| Tonghae is in the far east, but per the article it was
| launched from Sohae Satellite Launching Ground.
| wkat4242 wrote:
| Oh strange, in the news here it said Tonghae-Ri. Thanks!
|
| Edit: Aha I see it, I looked it up and it says it is from
| Tong _chang_ -ri which is where Sohae is, not Tong _hae_.
| This was what confused me.
|
| Little knowledge + too much wikipedia + assumptions =
| fake news :P
| dylan604 wrote:
| nah, fake news wouldn't have printed the correction and
| just doubled down on it
| xoa wrote:
| > _If you 're trying for orbit, don't you usually launch east,
| so that you get a boost from earth's rotation?_
|
| No, or rather it's somewhat more complicated. Yes there are
| many popular orbits (or deep space) where that's an advantage,
| but there are also lots of orbits where it's less so or even
| outright undesirable such as with polar orbits. Depending on
| the purpose of the launch in question it may be necessary to
| cancel out that energy which means it's actively more expensive
| to have it. Locations far from the equator get less either way
| and have to take that into account.
|
| Launch safety is critical too as well, nobody wants to have
| debris from a failed launch come down somewhere undesirable.
| For civilized countries that's anywhere that might cause
| damage, but even for dictatorships it'd include other countries
| they don't want to offend that specific way or alternatively to
| give insights into whatever they are launching that could come
| from wreckage analysis (failure in low first stage isn't going
| to mean stuff burns up like a deorbit). So even when a target
| orbit would indeed benefit from such a directly easterly
| launch, a dog leg is often part of it.
|
| Obviously NK is less than transparent about all this but the
| basic incentives are still there.
| dylan604 wrote:
| >For civilized countries that's anywhere that might cause
| damage
|
| Trying to find a joke for that applied to SpaceX/Starship.
| goalieca wrote:
| How fast will this be torn apart? I wonder what level of
| technology, sourcing of components, and quality of security there
| is.
| wkat4242 wrote:
| It's most likely already 'torn apart' by the impact and
| possibly explosion. A lot of parts will have sunk to the
| seafloor. And any analysis might be classified.
|
| Also I'm sure they are able to obtain components from the west,
| their border with China is pretty porous.
|
| But yeah I'm also interested to hear the outcome in case
| something does surface. Just wouldn't count on it.
| dmix wrote:
| It said it simply lost thrust and descended, I don't think it
| exploded.
| wwilim wrote:
| Plot twist - it was a spy submarine all along
| not_your_mentat wrote:
| Surprise.
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