These are serious amounts of nasty chemicals for those who work with or near them. Sometimes these rockets do blow up shortly after launch and create a hazard. But the USA-193 tank simply wasn’t a credible threat to anyone on the ground. Spacecraft fuel tanks are thin to save weight, and break apart quickly on re-entry. Hydrazine is flammable (it is a rocket fuel after all) so at most it would have briefly brightened the USA-193 re-entry fireball. BFD.

StevoR said:
> Now ok, it was rationalised – not overly convincingly – as a possible threat to people with hydrazine fuel but c’mon, there’s a lot of understandable cynicism about that!

Understandable cynicism. Maybe multiple reasons for the takedown. Doesn’t negate the hydrazine risk.

> Wasn’t there a lot of hydrazine or suchlike dangerous chemicals spilt when ‘Columbia’ broke up on re-entry? Seem to recall NASA using that as a warning-off from morbid ghouls picking up pieces of the shuttle debris and seling them on e-bay or whatever ..

Yes, there was some hydrazine on Columbia, and there was concern over contaminated parts. Not sure, but it sounds like you’re trying to belittle the hydrazine risk by saying Columbia had hydrazine, too. Couple differences. 1) Columbia had used up most of the hydrazine on board, vs this satellite having full tank. 2) Columbia broke up, dispersing most of the remaining hydrazine, while the satellite was predicted to have tanks survive reentry intact and thus have a large amount concentrated in the strike zone. Also, and this is significant, Columbia was intended to return intact, so breaking up and spilling hydrazine was not intentional, nor was scattering potentially contaminated parts across Texas.

“Aren’t there some serious issues here with the international (UN?) law on space -in terms if not militarizing space or using it for aggressive military purposes? ”

Should be :

Aren’t there some serious issues here with the international (UN?) law on space – in terms *of* not militarizing space or using it for aggressive military purposes?

Obviously!
—————
‘Needless to say’,
It need not be said
But so many needlessly say it.
Is this because its not ‘needless to say‘
And that’s why we so often say it?
For if its not needless
Then needs must we say
But if not we needn’t e’er say it!

Aren’t there some serious issues here with the international (UN?) law on space -in terms if not militarizing space or using it for aggressive military purposes?

Now ok, it was rationalised – not overly convincingly – as a possible threat to people with hydrazine fuel but c’mon, there’s a lot of understandable cynicism about that!

Wasn’t there a lot of hydrazine or suchlike dangerous chemicals spilt when ‘Columbia’ broke up on re-entry? Seem to recall NASA using that as a warning-off from morbid ghouls picking up pieces of the shuttle debris and seling them on e-bay or whatever ..

The real reasons being showing off to China and preventing it falling into non-US military hands strikes me as being much more credible. & just because China does something bad doesn’t mean the USA has to copy them .. “Great Powers” politics is so stupidly & dangerously childish on occassion.

(I blow up a satelite! Hah Hah! Hey! I can blow one up too! Ner,ner! Grow up please “Uncle Sam” and “Chinese Lil’ Emperors”!

In fairness, I ‘spose all three reasons could be combined to justify destroying Sat. USA-193 but … hmmn… as I said, mixed feelings & mixed messages there.

I am glad of one thing though – at least unlike in ‘Futurama’ they didn’t miss the real target and blow up Hubble by mistake!

Umm, ain’t a kinetic kill vehicle a warhead?

On second thought, maybe not. A bullet is a kinetic kill vehicle, and it isn’t considered a warhead.

I told you so, the odds of missing were nearly nil.

Enjoy your blog a lot (I write a vaguely science-themed blog). Thank you, thank you, thank you for the Heavens Above link!

Enjoy your blog a lot (a write a vaguely science-themed blog). Thank you, thank you, thank you for the Heavens Above link!

http://news.bbc.co.uk/1/hi/world/middle_east/7255657.stm

Gizmodo has the footage too. I prefer them myself, their videos load quicker.

It was an awsome show. Awsome.

[[Of course with a closure of about 30,000mph K=mv2]]

And Steve H writes:

[[The rest is simple F=MV^2 ]]

Guys, kinetic energy is

Ek = (1/2) m v^2

and force is

f = m a

Here Ek is kinetic energy (in joules in the SI), m is mass (kg), and v velocity (m s^-1). F is force (newtons), m mass again (kg), and a acceleration (m s^-2).

Check an introductory physics textbook.

BA, you sound as if you’re surprised by this fact. Others have chided you in earlier posts on your use of the phrase “blow up” when referring to this shot. Yet you used it again in this article? What’s up with that?

Breaking news! It’s going to hit Australia!! Near my town! Whoo hoo!

“China is continuing to closely follow the possible harm caused by the U.S. action to outer space security and relevant countries,” Foreign Ministry spokesman Liu Jianchao said Thursday.”

…Oh you slimy littles… YOU made harm, THEY actually waited for enough decay!

As for showing an image of the Hubble… wasn’t one of the Keyholes (KH-11) thought to have resembled Hubble? I had heard talk back when Hubble was launched that it was somewhat based on one of these spy sats.