NASA Studies Laser for Removing Space Junk

Today, James Mason at NASA Ames Research Center near Palo Alto and a few buddies describe a much cheaper option. Their idea is to zap individual pieces of junk with a ground-based laser, thereby slowing them down so that they eventually de-orbit. Of course, laser removal isn't entirely new. In the 1990s, the US Air Force studied the idea, thinking that a powerful enough laser could ablate an object, creating a force that could be used to de-orbit it. The trouble with this idea is that such a powerful laser has an obvious dual purpose, which is unlikely to please other space faring nations. So Mason and pals have studied the possibility of using a much less powerful system which uses the momentum of photons alone to decelerate the junk.

For Full Story Click Here


This is pretty cool…
With all that junk floating around I’m surprised we’re able to fly rockets and shuttles into space as well as we do… without incident

Surprised that this hasn’t already been built… It's something I actually think is useful... We rely on satellites too much... if a few crashed... that would, put a strain on our systems... and my TV might not work lol

Also I think it poses a great opportunity to build a global defense network… you know in case aliens invade us


-Evol Eric

Why doesn't all the debris fall back to earth and burn up in the atmosphere? they need to reposition satellites orbits all the time and the space station too. maybe the mass isn't enough for the earth to pull them in close enough?

reply to post by roughycannon

These objects consist of everything from spent rocket stages and defunct satellites to explosion and collision fragments. The debris includes slag and dust from solid rocket motors, surface degradation products such as paint flakes, coolant released by RORSAT nuclear powered satellites, clusters of small needles, and objects released due to the impact of micrometeoroids or fairly small debris onto spacecraft.[1] As the orbits of these objects often overlap the trajectories of spacecraft, debris is a potential collision risk.

According to good old Wikipedia
You are right... most of the junk is very very very small... but still...
couldn't the risk be compared to a bumble bee hitting your windshield and causing a fatal hull breach to your car?


But according to the same wikipedia page...

Impacts of these particles cause erosive damage, similar to sandblasting. The majority of this damage can be mitigated through the use of a technique originally developed to protect spacecraft from micrometeorites, by adding a thin layer of metal foil outside of the main spacecraft body. Impacts take place at such high velocities that the debris is vaporized when it collides with the foil, and the resulting plasma spreads out quickly enough that it does not cause serious damage to the inner wall. However, not all parts of a spacecraft may be protected in this manner, e.g. solar panels and optical devices (such as telescopes, or star trackers), and these components are subject to constant wear by debris and micrometeorites.

most of the debris poses lil risk... but still there is risk...
Personally I don't like the idea of a "bumble bee" hitting my "car" and killing me...

...think I will cancel my space agencies plans to send myself to the moon... at least until that laser is built

So what is this exactly? Is it part of seed to get humans used to the idea of seeing laser looking weapons shhot into the atmosphere while aiming at a target. Last time I heard this spoken about it was shooting at a craft just outside earths borders. The craft dodged it and probably could again.

I write this not to insult but to ask a question. What if the "aliens" up there are not all coming to get us. Are we to shoot and ask questions later or watch it shot and be told its to clean up the mess we made up there?

It wouldnt pose an issue to me if honesty were within the morals of our elected officials but since it isnt I see that article as covering some tracks for when we begin to see more weaponized lazers shooting at "stuff" in space.

I think the enemies that we need to worry about are walking right here on the ground and would love to be able to shoot things into space with plausable deniability on the alien topic to coinside with the benifit of the doubt. I think I see a seed being planted and wouldnt be surprised if this topic is spread around the internet much more in the days to come to get us all ready for it with a predetermined notion of what it already was.

say no to the lasers shooting into the sky. We are not barbarians and would like to give any visitors a chance to speak or fight. We offer each country the right before we go to war so why any different here. If a fight is what they want then we need to follow up with who is their enemy and why. It'll probably be another race other then us that has been enslaving the humans and the new comers wish it to stop. We could use the help.

Originally posted by roughycannon
Why doesn't all the debris fall back to earth and burn up in the atmosphere? they need to reposition satellites orbits all the time and the space station too. maybe the mass isn't enough for the earth to pull them in close enough?

That's a good question. I think the answer is, eventually much of it will fall back to earth and burn up in the atmosphere, but we don't want to wait that long as it poses a risk now, so the proposed laser method would greatly speed up that process. Also as the OP article says, we have to stop creating space junk:

Kessler pointed out that when the rate at which debris forms is faster than the rate at which it de-orbits, then the Earth would become surrounded by permanent belts of junk, a scenario now known as the Kessler syndrome.

The Chinese test that destroyed a satellite may have created over a million new pieces of space junk:
Anti-satellite test generates dangerous space debris

Millions of new pieces of space junk may have been generated during a Chinese test of an anti-satellite weapon

Regarding the mass, it's the opposite of what you said for the most part. It's actually the mass to surface area ratio that determines drag, and in general if densities are equal, the more massive the object, the longer it will take for drag to pull it back to Earth because its mass to surface area ratio is smaller, so the effect of drag is smaller on more massive objects.

Also you should familiarize yourself with Galileo Galilei. Before him people thought as you suggested that more massive bodies would be pulled faster to the Earth, but he is famous for proving that's not the case: Galileo Galilei - The Falling Bodies Experiment

Originally posted by Brianegan
I write this not to insult but to ask a question. What if the "aliens" up there are not all coming to get us. Are we to shoot and ask questions later or watch it shot and be told its to clean up the mess we made up there?

The answer is probably that NASA is looking at this technology for just what it says, to de-orbit space junk.

The military would be the ones thinking about defensive weaponry and probably the things they would be thinking about shooting at would be enemy satellites rather than aliens, though it would be interesting to know if they ever considered defending against an alien threat. The problem is, it's impossible to know what technology aliens would have until they actually show up, and besides that defending against a laser attack is pretty simple, all it requires is something as simple as a mirror. When the laser hits a mirror, it bounces right back, and no harm done to the hypothetical aliens, they wouldn't even need shields.