Satellite could plummet to Earth

[citivolus (Ric)]

The first Australian pass starts in about 14 minutes, over Adelaide. I don't know if anything large enough to be daylight visible will be entering yet, but it may be worth a look.

[glenc (Glen)]

Here is some more news: http://news.bbc.co.uk/2/hi/science/nature/7254540.stm

[rogerco (Roger)]

I must be the last person to hear about this, no TV for the last few nights.

Can someone tell me? Did they just hit it and the impact force broke it up or did they explode something? Its just I though a conventional explosion would require oxygen? So did they hit it with a small nuclear shell, which I think is against some treaty or other.

Roger

[Kal (Andrew)]

The satellite was travelling at more than 20,000 km/h so they didn't need a warhead, just the kinetic energy from the collision would be enough to detroy it

[fringe_dweller]

this via meteorobs group

'Taken from the Satobs list, quoting in turn a message taken from the RASC list:

http://www.satobs.org/seesat/Feb-2008/0450.html

A message posted on the mailing list of the Royal Astronomical Society of
Canada says in part:

at approx. 19:43 PDT while observing the lunar eclipse at the PGAO (53 45'
29" N 122 50' 56" W) a group of
about 30 people, PG Centre members and public, witnessed what we assume was
the demise of the spy
satellite USA 193.

Many debris trails were witnessed moving from south-west to north-east at
high altitude. One was especially
bright and long lasting. I can recall about 6 bright trails and 15 fainter
ones.

The debris trails seemed to come in "waves" with the first wave being
brighter than the debris that followed
behind it. The trails seemed to be in a fan shape with the trails being
wider apart in the north-east than they
were in the south-est.

Brian Battersby, Prince George Centre RASC

- Marco

-----
Dr Marco Langbroek - SatTrackCam Leiden, the Netherlands.'

[Outbackmanyep]

Sure it wasn't "Percy" the Taiwanese made UK satellite from "Supernova" ?? hehe

[glenc (Glen)]

The US is confident that its shooting down of a disabled spy satellite with a missile managed to destroy its potentially toxic fuel tank. Marine Gen James Cartwright said there was a 80-90% chance that the satellite's tank had been destroyed.
A fire ball, vapour cloud and spectral analysis indicating the presence of hydrazine all indicated that the tank had been hit, he told reporters.
The operation has been criticised by China and Russia.
"We're very confident that we hit the satellite," Gen Cartwright said at a Pentagon briefing hours after the missile was fired.
"We also have a high degree of confidence that we got the tank."...
http://news.bbc.co.uk/2/hi/americas/7256741.stm

[gaa_ian (Ian)]

This has been an Amazing Story to watch unfold to its ultimate climax. No wonder the Russians and Chinese are a bit unsettled !
It would have been great to be with the RASC group seeing the debris burn up !

[snowyskiesau]

Here's a DOD clip of the satellite's final moments.

http://www.dodvclips.mil/?&fr_story=...=oneclip&rf=ev

[gaa_ian (Ian)]

That is very cool Geoff !
It was front page news here yesterday in the NT as some of the debris could land here !
http://www.ntnews.com.au/article/200...21_ntnews.html

[glenc (Glen)]

http://celestrak.com/events/usa-193.asp
Assuming this information is correct and using the same approach as applied to the analysis of the orbital debris of from the Chinese ASAT test, we obtain the following chart. It shows the percent of the 169 objects which decay over time (at least 59 of which are reported to have already decayed), based on our analysis. The black line represents 10-cm objects and the blue line represents 20-cm objects. In the 10-cm case, the last object decays 67 days after the intercept; in the 20-cm case, the last object decays 113 days after the intercept.

[citivolus (Ric)]

Yes, I was very amused by that chart, especially in light of the quotes floating around in articles shortly after the press conference in which the intercept attempts were announced, where in some cases it was claimed that 50% of objects would re-enter within the first half orbit.