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India’s satellite destruction is threatening the ISS


ProtoJeb21
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India got the bright idea the other day to shoot down one of its satellites to prove it is a “space power” (getting a probe to Mars should be enough to prove that, and they already did so in 2014). They picked a satellite in a low enough orbit so no debris would cross paths with the ISS and risk the possibility of an impact. 

Just take one guess about how well that went. 

https://www.businessinsider.com/nasa-space-junk-india-destroying-missile-threaten-international-space-station-terrible-thing-2019-4

Debris too small to be tracked were thrown into orbits exceeding the station’s apogee, and now the ISS has a 44% chance of an impact with one of them, or 24 other fragments exceeding 10 cm (4 in) across, within the next ten days. To make matters worse, six astronauts are currently on board, and these fragments could end up creating an even bigger mess in LEO.

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Just now, Green Baron said:

Not sure if that isn't a politically motivated thing. The sources don't seem too trustworthy to me ....

Bridenstine may be politically-motivated but I trust that if he states a bare fact, it's true.

The idea of a 4" chunk of space debris catapulted up above the ISS orbit is terrifying. Impact with an object that large would shred an entire module in an instant. 

You need less than 30 m/s of dV to kick a piece of debris's apogee up to 400 km from a 300-km orbit. Kill vehicle impactor speed (relative) was probably well over 3 km/s. Really, really stupid. 

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30 minutes ago, Green Baron said:

Not sure if that isn't a politically motivated thing. The sources don't seem too trustworthy to me ....

It doesn’t really matter whether the source has political bias or not, because there’s no denying with the truth that what India did was stupid. Like I said before, they’ve already proven themselves with the Mars Orbiter Mission in 2014, and all they’ve managed to do this time was threaten the safety of everyone on the ISS.

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Just now, ProtoJeb21 said:

It doesn’t really matter whether the source has political bias or not, because there’s no denying with the truth that what India did was stupid. Like I said before, they’ve already proven themselves with the Mars Orbiter Mission in 2014, and all they’ve managed to do this time was threaten the safety of everyone on the ISS.

Weird they did not lowered the orbit of the satellite down to an orbit there the parts would deorbit fast. 
US did shoot at an satellite who was close to deorbit. 
Shooting at an upper stage who is already on an almost suborbital trajectory would also work. 

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28 minutes ago, magnemoe said:

Weird they did not lowered the orbit of the satellite down to an orbit there the parts would deorbit fast. 
US did shoot at an satellite who was close to deorbit. 
Shooting at an upper stage who is already on an almost suborbital trajectory would also work. 

I think that the perigee of the target was low enough to enable fairly rapid deorbit, but the collision would have been violent enough to kick up the apogee of some of the debris. The debris will still deorbit in a matter of months, but until then it will cross the ISS's orbit and will vary considerably.

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2 hours ago, ProtoJeb21 said:

Debris too small to be tracked were thrown into orbits exceeding the station’s apogee, and now the ISS has a 44% chance of an impact with one of them, or 24 other fragments exceeding 10 cm (4 in) across, within the next ten days. To make matters worse, six astronauts are currently on board, and these fragments could end up creating an even bigger mess in LEO.

Extra, extra! Read all about it! If you hit something, there are always fragments sent flying behind it!

Seriously, they could have just tried to build a maneuvering terminal vehicle that hits its target on the way down... if their ASAT was anything but a repurposed antimissile.

Edited by DDE
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Hi folks,

Several posts have been removed.  Please don't discuss politics here in the forums (forum rule 2.2.b).  Yes, we realize that this is a discussion involving a national space program, so a certain amount of discussion of that nation and its space program is unavoidable.  But please keep things focused on the space flight aspect of it-- i.e. the risks involved, etc.  Please don't sidetrack into a discussion of political motivation, or general political discussion (such as who's having an election when, etc.), because that's off-topic.

Also, kindly refrain from trolling, i.e. directly trying to provoke a reaction, per forum rule 2.2.n.

Thank you for your understanding.

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According to Wikipedia, there are >100 million pieces smaller than 1cm, and <1 million of 1-10cm, 34000 > 10cm of space debris flying around.

Nationalities aside, we do need a mechanism to clean up.

Edited by Green Baron
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3 hours ago, Green Baron said:

According to Wikipedia, there are >100 million pieces smaller than 1cm, and <1 million of 1-10cm, 34000 > 10cm of space debris flying around.

Nationalities aside, we do need a mechanism to clean up.

That's true, and making more is not going to help anyone.

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54 minutes ago, sevenperforce said:

I think that the perigee of the target was low enough to enable fairly rapid deorbit, but the collision would have been violent enough to kick up the apogee of some of the debris. The debris will still deorbit in a matter of months, but until then it will cross the ISS's orbit and will vary considerably.

It was no protest about the US sat kill, as in complains about debris, it was critique of the weak excuse that it was done to prevent toxic fuel reaching the surface and general dislike about weapons in space or weapons generally. 
I assume it was low enough that even if aP got high small fragments would deorbit in an orbit. If target is aerobraking hitting it is a bit harder as in good training and an good commercial :) 
Scrap the last one, nobody in marketing could come up with names like Standard Missile 3?  Why not something more catchy? S400 sounds way better by not sounding idiotic. 

 

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37 minutes ago, Green Baron said:

Nationalities aside, we do need a mechanism to clean up.

One man’s debris removal system is another man’s ASAT system.

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Great.  Way to go India.  I thought the global space community sought advice and made reference to such plans with everyone else before making such a move.  Nobody saw this coming?  Nobody attempted to coach and advise this nation's program of the move they were about to make?  The "ISS" being what it is, something doesn't seem right here.

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I've seen the 44% number thrown around a lot. In some cases it's used as "increased to 44%" but in others it's used as "increased by 44%." If it's the latter, then there's a chance that it's an increase above the last value. Like, if the chance of a collision was 0.000001, it is now 0.00000144, not that much of an increase. However, I've seen the 44% number used in different ways, so I don't know which of those it means. If it's "to 44%" then we have a problem, but otherwise we don't.

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Some more posts have been removed, due to 1. discussing politics and 2. trolling, after it was just posted above to kindly refrain from 1. politics, and 2. trolling.

Folks, "don't go there" means "don't go there".  Thanks.

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1 hour ago, Ultimate Steve said:

I've seen the 44% number thrown around a lot. In some cases it's used as "increased to 44%" but in others it's used as "increased by 44%."

The quote from Bridenwhatsit was "the risk went up 44%".  So whatever the risk was before, it's now at (risk)*1.44 over the next ten days.

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1 hour ago, Ultimate Steve said:

I've seen the 44% number thrown around a lot. In some cases it's used as "increased to 44%" but in others it's used as "increased by 44%." If it's the latter, then there's a chance that it's an increase above the last value. Like, if the chance of a collision was 0.000001, it is now 0.00000144, not that much of an increase. However, I've seen the 44% number used in different ways, so I don't know which of those it means. If it's "to 44%" then we have a problem, but otherwise we don't.

Yeah. The semantics of percent increase and percent probability are quite important.

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