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ISS Could Be Fitted With Lasers To Shoot Down Space Junk
An anonymous reader writes Japan's Riken research institute has suggested a new idea for dealing with space junk. They say a fiber optic laser mounted onto the International Space Station could blast debris out of the sky. From the article: "To combat the increasingly dense layer of dead satellites and miscellaneous space debris that are enshrouding our planet, no idea — nets, lassos, even ballistic gas clouds — seems too far-fetched to avoid. Now, an international team of researchers led by Japan's Riken research institute has put forward what may be the most ambitious plan to date. They propose blasting an estimated 3,000 tons of space junk out of orbit with a fiber optic laser mounted on the International Space Station."
Does poking holes space junk make it disappear or make more of it?
The idea of using lasers to de-orbit space debris has been around for a while.
http://adsabs.harvard.edu/abs/...
Back when I was working on lasers for power beaming, the idea was discussed as an alternate use for the ground-based lasers.
http://www.geoffreylandis.com
See, that's the mistake supervillains make... You need to start small. Start with a wealthy but small place, like Martha's Vineyard, so that the powerful know that this is coming for them, so that they can put pressure on their private government officials to make it happen. Then move on to bigger and bigger wealthy suburbs and cities until you get to Washington.
After all, if you destroy DC, you destroy the people that are authorized to pay you in the first place.
Do not look into laser with remaining eye.
Maybe they thought the closer the better?
Slashdot, fix the reply notifications... You won't get away with it...
Here is the problem. Blowing up or melting items does not work.
But if you heat up one side of an object, that side out-gasses or vaporizes and alters the orbit. Pick the side intelligently and you can slowly nudge stuff into a decaying orbit.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
Just imagine, you are done with they days duties on-board the ISS, then you slip into your jumpsuit and grab a stick and shoot down space junk. This is simply put, SPACE INVADERS for real :D
And the answer is...
None! We're not even talking enough laser to blind someone at that range, much less vaporize something/someone....
"I do not agree with what you say, but I will defend to the death your right to say it"
> Just leaves smaller material in orbit.
Yes, then you have to shoot them again to score more points. At least this doesn't have B&W vector graphics.
My guess is that the power of the ISS laser, if aimed at the ground, would cause less damage than aiming a laser pointer at the ground. For all of the sci-fi programs showing space-based lasers decimating cities, our atmosphere is very good at diffusing light and the ISS's laser isn't going to have the power needed to overcome this.
My sci-fi novel, Ghost Thief, is now available from Amazon.com.
think of the ants, you insensitive clod!
Launch "Aerogel" producing satellite robot.
Grow immense Aerogel sponge(s).
Push the sponge(s) through the most contaminated orbits.
so why bother.
"Win treats sysadmins better than users. Mac treats users better than sysadmins. Linux treats everyone like sysadmins."
there is a better article here: http://www.csmonitor.com/Scien...
you can read the full paper (for free) here: http://www.researchgate.net/pr...
Anons need not reply. Questions end with a question mark.
My understanding (as very limited as it is), is that you'd need to ablate enough material off the object to knock it out of orbit and to fall to earth.
However do you even need to hit it that hard? Can you just put enough laser energy on to it to perturb it out of orbit without ablating/vaporizing material? More massive objects would of course require more power applied.
Ok, this is a nice plan and all, but there is one little problem: how do you keep the sharks alive in a vacuum?
The only thing necessary for evil to triumph is for it to be pitted against a slightly greater evil
Planetes was a cool anime until near the end when the characters all when off the damn rails.
Anyhow, the headline and description are terrible. The plan is not "blasting" debris out of space. They're using the lasers to degrade the orbit. The atmosphere would then destroy the debris. Of course, using lasers to "burn", "propel", or "push" the debris out of orbit doesn't sound nearly as sexy as "blasting" it. So, for everyone talking about how "blasting" will simply create more debris, it's not an issue.
Irony: Agile development has too much intertia to be abandoned now.
How does heat affect the orbit?
You vaporize one side of the object, and the expanding gases provide some thrust.
All the laser has to do is slow the junk down, just shining the object with the laser will impart a force which will cause a slowing of momentum. Once momentum of the object has slowed below orbital speed, it should fall towards earth and burn up in the atmosphere. Tracking should not be that hard as radar aimed weapons have been around for many years. How much energy and for how long to illuminate is up to the designers.
Passionately Indifferent
After all, if you destroy DC, you destroy the people that are authorized to pay you in the first place.
That, and you completely destabilize/devalue the very thing you are demanding. Your $100B USD won't go far if the US government collapses. Better ask for Gold or Bitcoins.
All of it will eventually deorbit, it just might take a while.
Much of the trash is from military and commercial launches - singling out "the scientific community" is silly.
Oh boy, that was such a flame-bait post.
Just cool down, man, the ISS is still up there and still useful -- this (shooting space junk) is just a good example of it.
Besides, if the US Governement had invested in space research and (cheap, reliable) space access, you guys would not be at the tender mercies of the naughty naughty Russian bear. So you only have yourselves to blame here...
The right to offend is far more important than the right not to be offended. (Rowan Atkinson)
Everyone would cheer if they went after Martha's Vineyard or Cape Cod. It would solve more problems than it causes
if you break space junk up it continues on the same orbit.
The force of gravity is proportional to mass, so the acceleration doesn't change if you break an object into parts. However, other effects are not proportional to mass, in particular atmospheric drag and radiative pressure. In low Earth orbit, there is still enough gas around to drag small bodies and dust down over the timescale of months or years.
And radiative momentum transfer can't exceed the momentum of the photons hitting it which won't be a lot or you'd also be pushing on the space station too.
Radiative pressure is all about the ratio of surface area to total mass. Large objects like the space station are pushed on by radiative pressure, but they have relatively small surface area for their mass compared to say dust. Near earth, the pressure from sun light is about 9*10^-6 Pa. If this were applied to a 1 m^2 surface area object that had a mass of only 1 kg (e.g. a solar panel with nothing else attached), its speed would only change by ~1 cm/s after half an hour. For dust a couple microns across and made of metal, that would ~1 m/s delta-v instead. This adds up after many orbits.
Doesn't work
Yes it does.
Here is the problem. Blowing up or melting items does not work.
Here is the solution: don't do either of those things.
systemd is Roko's Basilisk.
Little did I know that this was the long-term plan planted by the Government implemented by Atari. My years of playing Asteroids will now lead me to picked up by a government van, dropped at Fort Lauderdale, where I will be immediately transported into space to fill my destiny.
Just like The Last Starfighter! (Did I date myself too much...)
Therefore, we shall call it the Alan Parsons Project.
None because the atmosphere does a fantastic job of absorbing energy from laser blasts.
If you want to kill people from orbit, you should take bricks up with you and throw them out the airlock, it's way more likely to succeed.