http://techfox.comicgenesis.com/d/20041112.html

For instance, exactly how did you determine the percentage of kinetic energy that resuults in spacecraft damage? What is your conversion rate of Joules to tons of TNT?

(Please do all work in metric…along those lines, is tons of TNT a metric ton or a British ton?)

Thanks. This just gets everyone on the same page and provides a nice physics primer for verybody.

I imagine that the actual lines of motion were less than perfectly aligned. The resulting “glancing blow” would cause both birds to leave the scene spinning very very rapidly which would cause them to rip apart into thousands of fragments.

Taking the total kinetic energy of both objects only works if they end up in a single mass and and then you still have to subtract the KE of the resultant blob.

There is no way to ever know how much energy was released. One thing is for sure. At those speeds on a crossing vector there was plenty of energy to destroy both birds.

Nor am I not anti-jewish, just Pro-Palestinean!

Actually pro-Humanity when you think about it. Israel violates international law, basic human rights principles, committs endless war crimes and creates anti-semitism daily. (& not just anti-Palestinean and anti-Arab variety anti-semitism but anti-semitism directed, rather justifiably, against the perpetrators of so many war-crimes and crimes against humanity – Israel & the wider Israeli-Jewish lobby.)

Ultimately, Israel will harm everybody incl. the Jews themselves. There is no better way to wipe out the jewish people, should you actually want to – which I don’t – than get them all together in one small piece of land then really, & I mean really get the neighbours of that land to hate you.

Israel will not remain militarily superior forever. One day it will lose its ability to terrorise its neighbours into submission – and will have the choice – learn to respect & get on well with its neighbours – or perish.

It is hardly naive to think Mutally Assured Destruction works the USSR-USA Cold War & the current India-Pakistan situation is proof of that.

Mahmoud Ahmadinejhad is certainly no crazier than “Dubya” Bush and Iran too has a right to exist without fear of attack.

Why might I ask should Israel and USA, nations demonstrably more aggressive and with far worse records of respecting the rights of others have WMDs and yet not Iran? There is no answer for that question which is not blatant hypocrisy.

@ Ragutis : (Feb 12th, 2009 at 2:58 am)
StevoR, I don’t hesitate to criticize and condemn Israel for it’s criminal behavior against the Palestinians over the years, but you have got to be nuts to think that a nuclear Iran is a good idea. Nuclear weapons are a terrible idea in any circumstance, but imagining them in the hands of a theocracy is blood-chilling.

Too late. Israel is a religio-racist apartheid military theocracy – & it already has secret nukes in violation of UN law. The US was ruled until recently by a man (in the loosest sense of the word) who believes God told him to invade Iraq. I’d prefer Iran had nukes than either of those nations -its record on the international stage is much more responsible and peaceful!;-)

(It is historical fact that Iran hasn’t actually attacked any other
nation since WWII – but rather been attackied by a few notably Iraq with
Amercian encouragement.)

Ragutis continued :
… Yu want a quick solution? Get rid of that nutjob Ahmadinejad and overthrow the Supreme Leader. Iran has a huge youth population that are quite progressive and would really like to Westernize.”

Sounds like the neo-cons plan for Iraq. Weren’t we going to be greeted
with flowers and cheering crowds there?

No. Reigeme change just does NOT work. Accept it. Just because the US doesn’t like some other govt does NOT give it the right to attack that nation. Its time this axiom was acknowledged and the US stopped itshysteria and started behaving more responsibly and multilaterally – hopefully Obama will the USA in that direction.

“An aggressive U.S. and Israel only helps the reactionaries and clerics remain in power.”

Now on that we agree!

As for emoticons, well I like ‘em!

Oh & the reason I was worried about my post coming though wasn’t paranoia – I’ve just had a few problems posting things on other threads here before.

I was playing fast and loose with the terms the way I would with a layman, refering to the fact that in state 1 we had a chunk of metal going in a straight line and in state 2 we had a million chunks of metal going every which way liberaly mixed with rapidly cooling metal gas/plasma.

I wasn’t trying to say anything profound physics-wise, just that Madscientist had his definition of explosion wrong

Haha – weight indeed. OK, so it’s the mass of each satellite which is quoted. As for the weight, they’d weigh slightly less than they would on earth with their given orbit. After all, gravitational acceleration is proportional to 1/r^2 and at the surface that’s already 6300km, so at the altitude of the orbit r~7080km. Unless I got sloppy with punching buttons, that means the weight is about 79% of what it is at earth’s surface.

For the less physics inclined, at the ISS orbit and the range of shuttle orbits, the occupants are *not* weightless – for example, trips to the ISS give you about 87% of your weight and the highest shuttle missions were roughly at the altitude of these colliding satellites. The reason we see astronauts, cosmonauts, and others ‘floating’ in the cabins is that the spacecraft are falling as fast as its occupants – this is just what happens on the ‘vomit comet’ except that the spacecraft are perpetually falling whereas the vomit comet needs to pull out of the dive before it hits the ground.

Now onto the BA’s latest post and apology for his goof-ups …

I know a guy who was involved with that bird. Solwind was a solar observation satellite that was failing. Most of the instruments were dead. The software workarounds (it needed to be reconfigured repeatedly) to continue testing with the remaining instruments were causing problems on the sat control network, so they flagged it as a convenient ASAT test in 1985. All debris was down by the early 1990s. In fact, the results of that test were used as lessons learned in the US193 shoot down.

heasarc.nasa.gov/docs/heasarc/missions/p78-1.html

The main complaint against the Chinese ASAT test was the altitude. It was way out of the atmosphere, so you get debris lasting indefinitely. It was also a kinetic energy weapon instead of a warhead, so there was nothing *but* debris. Over 2000 chunks of trackable size, and it single handedly increased the number of tracked object by over 20%.

That or most painful styrofoam ball fight ever. “Ow! Why’d you have to throw a satellite-debris ball at me, man!”

The Juice? Isn’t he in jail in Vegas now?

Make sure they get one with the Black Hole attachment.
Gravity is the only thing that sucks in a vacuum.

If we really want to travel in space, we really need to work harder at preventing this sort of thing.

Wish we had video. It’s a shame it happened, but at least then we’d get a cool wreck out of it.

Remember, there is a small amount of atmosphere even out to 1000 Km. Left to themselves these sats orbits would eventually decay and impact the denser atmo, burning them up. Which is why we have to keep boosting the ISS, just to maintain its orbit.

GAry 7