View Full Version : Ep. 82: Space Junk

2008-Mar-31, 05:40 PM
We're polluting every corner of our own planet, so it only makes sense that we'll take our trashy habits out into space with us. This week we look at the myriad of ways we're messing up space, from the trash orbiting the planet to the radiation we're leaking out into space.http://feeds.feedburner.com/~r/astronomycast/~4/261409562

More... (http://feeds.feedburner.com/~r/astronomycast/~3/261409562/)

2008-Apr-03, 04:38 AM
I started a thread elsewhere that is related to the topic of this show but not close enough to ramble along in this thread.
Space Dump (http://www.bautforum.com/space-exploration/72385-space-dump.html)

2008-Apr-05, 07:45 AM
The stuff that we have left on the Moon and other bodies didn't certain me as much as the stuff in orbit....until I heard about the microbes! Ouch! I thought some spacecraft was sterilzed before launch. That seems like a good, especially if it is going to some place with an atmosphere.

But yet, this program talks about microbes that have survived on the moon and tomato seed in orbit. At least they can't grow there!

But on the orbiting junk, Dr. Gay said that changing orbits is easy if you are not in a hurry. That got me thinking about an automated system that could use solar sails to deorbit junk. Ideally, you like the sail to be able to deorbit some junk and then detach and change configuration to go back in orbit and move to the next object. Would that be possible?

2008-Apr-17, 01:46 AM
The only way I think a solar sail could work is if you use it like a parachute to slow the junk down using the drag on the upper atmosphere. Then it could fold up and fire its ion engines to get back into a higher orbit. I think whatever acceleration you would get from the sail would be fairly small compared to the drag caused by the sail on the upper atmosphere.

Of course, that would only be useful if you're trying to bring something in low earth orbit down to be destroyed. The stuff that's farther out wouldn't really need to be adjusted since their orbits are stable but I guess it could be used if you're trying to move something farther away from the earth.

2008-Apr-24, 03:30 PM
Hey, a robot could attach small disposible sun sails to the smaller stuff (the stray nut or bolt), do the dive and ion drive back for the medium stuff, and for the larger stuff, use the ion drive to move it to a stable common orbit with Other Things - a Cosmic Junkyard area. Maybe even tie it all together.

There has also been some (unsuccessful, if I recall) experiments with using tethers for orbit change. This project could explore that further, maybe with a separate robot, and once the technology was viable, it could be used to collect the junk. This is all significant AI challenge or a great place for students to place practical celestial mechanics, under proper supervisor, of course. Yes, I am assuming the problems are non-trivial. But so would a bolt through the helmet of a space walker. The image of a cracked Space Shuttle window from a paint chip is haunting.

2009-Jan-13, 07:58 PM
Pamela mentioned that ISS astronauts throw trash in zip lock bags out into space. Is that true??? If so, how is that justified?

2009-Jan-14, 08:18 AM
Pamela mentioned that ISS astronauts throw trash in zip lock bags out into space. Is that true??? If so, how is that justified?

I thought they returned trash to earth, it came back with them.

2009-Jan-14, 06:08 PM
That's what I assumed too. But at 2:15 and 7:00 minutes into the episode Dr. Gay mentions the zip locked junk "hurled into space". Surprises me if the existing space junk is already a damage threat to the ISS, not to mention other space junk issues.