Reminds me of the anime Planetes, about a group of space garbage collectors. In the opening scene, you're shown an innocuous looking screw floating in orbit for something like 10 seconds, and then suddenly a traveling ship appears from the distance, and the screw goes straight through like a bullet, causing all the passengers to die. I don't know how realistic that was, but it really set the tone for the importance of the characters' job in keeping the orbits clean.
What I love about this scene is the proper portrayal of relative velocities in orbit.
You see a slow-moving ship. You then watch a slowly-drifting screw. Then, at the moment they're shown together, you realize their relative velocity is like that of a bullet.
(Also, I love the anime. It tries to handle space with as much scientific realism as possible. Also, even though it frequently shows the worst aspects of humanity, it also shows the best, and overall is pretty hopeful about space.)
"This video contains content from BandaiChannel, who has blocked it in your country on copyright grounds"
It bothers me that crossing an invisible line in the ground blocks access to stuff that others can see simply by standing on a different patch of dirt.
(With the added irony that this is a Japanese show, in the Japanese language, and I am physically in Japan at the moment.)
I had not heard of it before. Thank you for sharing it.
Unfortunately, the login page shows as invite-only; instructs me to contact the workspace admin for access; but doesn't give any obvious way to contact that person.
If you are an admin and would like to invite me, I have an email in my profile.
Comments here seem to agree there is too much junk in space, it's out of control, and a problem.
It's nothing compared to the amount of junk on the ground and in the oceans. Let's also work on lowering that, I propose starting with each of us -- including you -- refusing disposable stuff and acquiring less stuff in general.
It's the forgotten point of reduce, reuse, recycle. People are almost always surprised when I mention that it's a ranked list, heading towards less efficacy. You might be proud of recycling, but it's the low hanging and least useful choice. Simply not using things or re-using sturdier goods is far and away the better choice in terms of waste.
The closest object to Earth is a tank, which suggests a high-inclination launch. I guess Baikonur?
Next, you see a band of debris on less-inclined orbits. Those are close together, suggesting maybe fairings, or remnants of explosive stage separation? Stuff in space will drift apart like that, if you give it a slight push.
Presumably you picked a launch where the Briz, which is a tug stage that the Russians use for Proton launches to GTO, blew up after releasing the satellite in GTO. That's not supposed to happen, but at least it results in debris with a low perigee that will decay in < 25 years, maybe a lot faster.
Briz also drops a fuel tank early on.
Fairings are dropped while sub-orbital. India put one in orbit last year, but not intentionally.
Yeah Breeze-M is a Proton upper stage, which means a Baikonur launch. Unrelated fact: due to Baikonur high launch inclinations it's cheaper (in terms of dV) to circumnavigate the Moon when launching stuff into GEO than to change the inclination at the insertion burn. It's just not practical to do so, because the stage lifetime is limited.
This is an unbelievably well done visualization. Really helps one understand the degree of problematic space junk, though I don't have much of an intuition for collision probabilities.
Keep in mind that dot sizes are hugely exaggerated. Additionally, it's hard to see how the slow moving dots can collide, this visualization can only show the general sense of "how much stuff there is in orbit", which can be entirely misleading and doesn't reflect the real problem.
To be helpful in understanding the problem, it should probably include collision probabilities and relative velocities involved. It will be immediately ovious that, for example, GEO is absolutely safe despite having quite a bunch of "dots", and the most dangerous place is 15 and 14 orbits per day Sun-syhchronous orbits, where the most remote sensing stuff lives.
arbitrary motion collision is almost zero, the dots are several orders of magnitude larger than proper scale would be. But still "high enough to require taking into account when putting something else into orbit".
The odds of one object soon colliding with another object in particular are extreme, but this is a kind of 'birthday paradox' situation. I cant figure it out at hand, but one satellite out of thousands might end up with the same 'birthday' as another not too infrequently.
The visualization shows interesting behavior at the poles. Objects seemingly spinning around the Arctic and Antarctic. Is that an artifact of rendering or do they actually behave that way?
An orbit that swirls only around the poles wouldn't be a real orbit, but there are lot of real "nearly vertical" (90 deg inclination) orbits that just barely miss the poles. Taken together these objects give the impression of the swirling 'bald spots' you've noticed.
Adding to this, if you use the controls, and slow down the render speed, you will see that the objects are not circling the poles. It's just that there are many objects in high inclination orbits that pass near the poles, but comparatively few that actually pass over the poles.
Is it not reasonable to put a laser on a satellite with targeting systems to shoot some of this stuff? It seems like that would be ideal, no ammo needed, no super big nets or propellant (or less anyways).
If you target a bigger piece on one side it could cause a reaction to push it towards earth. If it's a small piece, it may disintegrate it. If it's spinning, it may alter it's orbit to eventually fall, etc...
Is this an unreasonable concept? I know this stuff is hard to find, but here we have a data showing we know where some of it is, and add some radar/lidar/whatever-dar to the satelite and get it a shootin. And no, I don't think a spacebased laser for shooting junk could harm anything planetside.
Impractical and it only makes matters worse since it can turn bigger debris into multiple smaller ones. Rather than shoot stuff with a laser, why not use a vehicle that generates a magnetic field and at least collects feromagnetic debris in one place. Then throw the whole thing into the atmosphere to burn and crash in an unpopulated area.
Lots of debris is likely not magnetic, and much of this stuff is miles away from eachother traveling at incredible speeds. You couldn't make a device fast enough to change direction and have enough magnetic force to capture much.
>...it only makes matters worse since it can turn bigger debris into multiple smaller ones.
That's the question, would it though? Real lasers don't behave like hollywood lasers. And are smaller pieces worse than large ones? Maybe the type of material could be detected, and laser based cleaning would work perfectly well with some types of material?
I suspect a laser would melt and cut up debris. Void is an insulator and the only way to dissipate heat is through radiation.
Smaller pieces are worse because they're more numerous if you break up a bigger piece and harder to spot and avoid. Also the probability of a crash increases with the number of debris.
Sure, but my understanding is that there are so many micrometeors already, they can't leave windows open to space for any extended period of time. There's already tiny particles flying around that they can't do a think about about. This implies that more small stuff shouldn't matter in the least, as they already have no choice but to have protection against this.
That means, there is a size small enough that it's no longer an issue. For someone knowledgable, I think it's simple to determine a ratio of size/speed/material type to determine whether or not to shoot the object with a laser or some other method.
Energy is the bottleneck. Lasers don't provide that much kinetic energy... so you're either briefly firing a powerful laser or continuously firing a small laser. The other energy cost is movement, I don't know how often the satellite would have to move to find debris but the larger satellite has more mass while the smaller one has to expend energy to match debris orbits.
Consider the output of gases from the material being vaporized, that is the thrust/kinetic energy. I don't know the math or the engineering behind lasers to know range, but I suspect in space, it's a lot further than on earth. And possibly cooling is less of an issue? (doubt it though)
Also, rotating mirrors would aim laser, not rotating the satellite. If cleverly done, could point any direction.
Cooling would be more of an issue in the vacuum of space. Even my little engraving laser requires water cooling, that satellite would be covered in radiators. Don't forget the targeting system needs power and cooling too.
Mirrors... Shooting from above is the "cleanest" shot. Hitting debris at an angle will change the debris orbital path (non-deterministic for rotating junk) until it re-enters the atmosphere. That's a risk for space control, which relies on predictable orbits.
Capacitors are a solution if the laser requires far more energy than the solar panels, but that lowers the cleanup rate of one satellite.
Like I said, the idea works. However, there are tradeoffs between price and results - I don't know that there's a practical balance.
Sure, the cooling thing I suspected, only because of reading about space suits a long time ago. Are there no lasers that don't require cooling?
Of course this is all theory, doesn't every good solution start with a theory, then a poorly functioning prototype before you ever get something truly useful?
Wow:
“A small piece of Cosmos 2251 satellite debris safely passed by the International Space Station at 2:38 a.m. EDT, Saturday, March 24, 2012. As a precaution, the six crew members on board the orbiting complex took refuge inside the two docked Soyuz rendezvous spacecraft until the debris had passed.”
KSP's stock career mode does have missions involving retrieving individual pieces of debris. Though it's not framed or incentivized as "removing space junk" in exactly the way you mean.
There's also an anime series about space junk, 'Planetes' (https://en.wikipedia.org/wiki/Planetes) -- which does the best job I've seen in any visual media of getting orbital mechanics right, and is generally somewhere between 'The Expanse' and 'Seveneves' on the scale of sci-fi "hardness". And, as far as anime goes, is relatively light enough on "anime bullshit" to be watchable even if you're normally not into that.
Is there a convention about in what direction you should put satellites ? I know the space is crazy big and it's unlikely you will front-collide with a satellite going the opposite direction. But it would also be crazy to collide with another object at 7,000 m/s
I guess most are in the same direction as earth rotation for practical reasons: Relative velocity to the surface is lower, which probably makes communication easier and requires less energy for launches (as you get a "boost" from earth).
Brilliant!!! Absolutely brilliant!!! So much detail and functionality. Recognition to James Yoder for this amazing product!! But also consider what this represents: From 1957 to now... how much our world has changed.
