Pollution by space crafts

There was a scheme a few years ago to launch spacecraft by dropping a number of nuclear devices out of it's innerds at regular intervals and detonating them. While energy-efficient and weight-efficient according to theoretical calculations, the predicted effects on the atmosphere and the surroundings of so doing are not recorded.

Would the last one to leave please put the lights out?

a nuclear type engine has been tested, tho after finding it works, the site was buried, that was many yrs ago.

It depends on the propellant. Liquid hydrogen + liquid oxygen like was used on Apollo burns clean. Hypergolic fuels, like hydrazine combinations can be quite toxic and nasty. Space Ship 1 burned old tire rubber and kerosene, IIRC.

NASA, and presumably other space faring entities, are moving in the direction of cleaner fuels, cleaner processes and cleaner materials.

I'll also point out that there are many more unmanned rocket flights than manned ones, and all space flight combined is out-polluted by normal earth based aviation, which is, of course, out-polluted by automobiles.

Thanks,

ur posting was informative.

Laxmandas

Hydrazine is very nasty. I have been to a launch pad; MESSENGER Launch, if anything were to happen, it's over in a blink of an eye. All the fuel burns at once, not like a gasoline fueled fire. Now if ya approaching the pad there are sensors and alarms that warn ya if there's a hydrazine leak and ya might have the time to leave.

But the fun out weights the danger

Something I've wondered about also. Each shuttle launch burns 352,000 lbs. of aluminum. I guess we're just lucky its is only occasional.

http://en.wikipedia.org/wiki/Space_Shuttle_Solid_Rocket_Booster

When the Challenger blew up, there was speculation (soon disproved) that its fuel tank had been hit by a high speed, metallic paint chip. The article I read claimed that there is a ring of debris in permanant orbit, moving at very high speed, all generated from separating rocket stages. I haven't heard anything about that, since.

Has anybody else?

It's not just down here man leaves mess.

There is a lot of junk flying around earth orbit at incredible speeds. It wouldn't have been an issue with Challenger though, because it broke up at a relatively low altitude.

There was some damage to one of the radiator assemblies (IIRC) a couple of shuttle flights back though - a tiny piece of circuit board went through the shuttle like a rifle shot.

It's not just paint chips - there is debris of all kinds. A Chinese satellite blew up just a while ago, and generated a major cloud of debris.

Thousands of chunks of garbage are monitored by radar, but there are gazillions more that are too small to follow.

And keep in mind that a typical earth orbital velocity is 18,000 mph, and impact energy is proportional to the square of that.

Also keep in mind that the relative velocity is what matters. If I'm traveling 18,000 mph and hit an object moving 18,001 mph, I see only the 1 mph and would not expect damage. If, however, I was orbiting in the opposite direction, the closing speed would be 36,000 mph. OUCH!!!

NASA just released the first draft of the Programmatic Environmental Impact Statement for the new Constellation space program. You can download it here:

http://www.nasa.gov/mission_pages/constellation/main/peis_noa.html

(click on download PEIS)