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Intelsat 33e breaks up in geostationary orbit

(spacenews.com)
157 points milgrim | 16 comments | 21 Oct 24 14:09 UTC | HN request time: 0.735s | source | bottom
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nordsieck ◴[21 Oct 24 14:28 UTC] No.41904557[source]▶
It is particularly bad for a satellite in geostationary orbit to break up or fail. Satellites are packed as tightly as possible into that orbit due to its economic importance (it's very useful for a satellite, particularly communications satellites, to always be over the same part of the Earth), so there is a higher than normal likelihood that this could be seriously disruptive.
replies(7): >>41904586 #>>41904693 #>>41904725 #>>41905123 #>>41905207 #>>41905406 #>>41906037 #
accrual ◴[21 Oct 24 14:32 UTC] No.41904586[source]▶
Indeed, Intelsat 33e has a couple nearby neighbors in similar orbits and inclinations.

    ID      Name                    Orbit   Incl.
    98050A  ASTRA 2A                57.2    4.93
    09017A  WGS F2 (USA 204)        57.5    0.01
    14023B  KAZSAT-3                58.5    0.02
    12008A  BEIDOU-2 G5             58.7    2.10
    16053B  INTELSAT 33E (IS-33E)   60.0    0.04 <-- 20+ debris components
    19014A  WGS 10 (USA 291)        60.3    0.01
    04007A  ABS-4 (MOBISAT-1)       61.0    3.86
    10008A  EWS-G2 (GOES 15)        61.5    0.04
    19049B  INTELSAT 39 (IS-39)     62.0    0.02
https://www.satsig.net/sslist.htm
replies(1): >>41904962 #
nordsieck ◴[21 Oct 24 15:03 UTC] No.41904962[source]▶
Looks like WGS-10 is the closest.

From Wikipedia, it looks like it's a USSF satellite launched in 2019 with a service life of 14 years. It provides wideband communications to DoD customers.

https://en.wikipedia.org/wiki/USA-291

replies(1): >>41905263 #
1. bryanlarsen ◴[21 Oct 24 15:33 UTC] No.41905263[source]▶
It's 0.3 degrees ahead in orbit. Which means the debris needs to speed up to collide. It's possible if the break-up was explosive, but most, if not all of the debris is more likely to stay at the same velocity or slow down.
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2. taftster ◴[21 Oct 24 15:55 UTC] No.41905461[source]▶
So does that mean the other satellites "behind" it are in more danger?
replies(1): >>41905770 #
3. Aachen ◴[21 Oct 24 16:01 UTC] No.41905536[source]▶
Speeding up does not work, that'll just put it in a higher orbit. My understanding of these issues is that introduced eccentricity gets you: if it takes the "inside corner" (is that the English word for binnenbocht/innenkurve?) around the earth, it could then then meet you on the other side where the orbits intersect. If it sped up (flying out of the corner, in this race analogy) and thereby took a longer way around, it'd rather be a danger to those immediately behind (with each orbit, progressively further back along the circular orbital path)

Disclaimer: this comes from playing a self-made orbital mechanics game, I have no training whatsoever let alone professional experience with this

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4. panki27 ◴[21 Oct 24 16:12 UTC] No.41905644[source]▶
My KSP experience supports your view :)

Parts that were sped up have their opposite orbital side raised, parts that got slowed will have their opposite orbital side lowered.

5. lupusreal ◴[21 Oct 24 16:14 UTC] No.41905660[source]▶
Most of the debris will have eccentric orbits with varied periods which intersect geostationary orbits. Every satellite in a geostationary orbit is at risk, not just the ones near it.
6. bryanlarsen ◴[21 Oct 24 16:22 UTC] No.41905737[source]▶
Any velocity changes will only happen once so will result in an eccentric orbit where only one side of the orbit is raised or lowered -- the other side will still be in SSO.
7. bryanlarsen ◴[21 Oct 24 16:27 UTC] No.41905770[source]▶
The one behind it is 1000km away vs 200km away for the one in front.
8. sangnoir ◴[21 Oct 24 16:27 UTC] No.41905776[source]▶
> Speeding up does not work, that'll just put it in a higher orbit

Speeding up doesn't raise the orbit; it makes it (more) elliptical while still intersecting with the old orbit (shared with neighbouring satellites)- you need at least 2 maneuvers to raise an orbit. You're also assuming a perfectly pro-grade acceleration. In an explosion, different pieces go in different directions, I suspect there is a vector that results in faster speed in the same orbit, but I'm no rocket scientist.

replies(1): >>41908768 #
9. Reubachi ◴[21 Oct 24 17:37 UTC] No.41906391[source]▶
How does one tell the dynamics of orbital objects/debris relative to forces acting on them? Is there a name for this type of field?
replies(2): >>41906752 #>>41907545 #
10. pavel_lishin ◴[21 Oct 24 17:45 UTC] No.41906479[source]▶
> this comes from playing a self-made orbital mechanics game

My interest is piqued!

replies(1): >>41913501 #
11. ◴[21 Oct 24 17:59 UTC] No.41906627[source]▶
12. simne ◴[21 Oct 24 18:10 UTC] No.41906752[source]▶
Ballistics.
13. visviva ◴[21 Oct 24 19:28 UTC] No.41907545[source]▶
Astrodynamics
14. sangnoir ◴[21 Oct 24 21:36 UTC] No.41908768{3}[source]▶
Correcting an inaccuracy in the last sentence I introduced in an edit: Kepler's laws means you cant have different velocities in the same orbit - bit its possible for an explosion to cause a projectile to intercept a satellite that was ahead of it in a new orbit.
15. Aachen ◴[22 Oct 24 12:16 UTC] No.41913501{3}[source]▶
Thanks, but don't expect too much! (In particular on mobile where you can't zoom by scroll wheel or use arrow keys to fly.) I mentioned it in an earlier comment, probably easiest to refer back to that for some context/hints: https://news.ycombinator.com/item?id=35763506
replies(1): >>41914557 #
16. pavel_lishin ◴[22 Oct 24 14:17 UTC] No.41914557{4}[source]▶
Thanks! I'll check this out later today.