Scientists Spot Space Junk With Lasers In Broad Daylight 37
Researchers from the Institute for Space Research at the Austrian Academy of Sciences have developed a technique in which lasers can measure the position of space debris during daylight conditions. Details of this unprecedented achievement were published in Nature Communications. Gizmodo reports: Prior to this, lasers could only detect space junk during twilight, as ground stations enter into darkness and objects near the horizon remain illuminated by the Sun's rays. This small window of opportunity severely minimizes the amount of time available to search for and characterize these orbiting objects, which can threaten crucial satellites.
"We are used to the idea that you can only see stars at night, and this has similarly been true for observing debris with telescopes, except with a much smaller time window to observe low-orbit objects," explained Tim Flohrer, Head of ESA's Space Debris Office, in an ESA press release. "Using this new technique, it will become possible to track previously 'invisible' objects that had been lurking in the blue skies, which means we can work all day with laser ranging to support collision avoidance." The new technique differs from conventional methods in that it can track objects during daylight hours, which it does using a combination of telescopes, light deflectors, and filters that track light at specific wavelengths. So even when the sky is bright and blue, scientists can increase a target's contrast, making previously invisible objects visible. Keys to this method include additional telescopes and the ability to visualize space debris against the blue sky background in real-time. In daylight tests, the distances to 40 different objects were measured with the new technique, which had never been done before.
"We are used to the idea that you can only see stars at night, and this has similarly been true for observing debris with telescopes, except with a much smaller time window to observe low-orbit objects," explained Tim Flohrer, Head of ESA's Space Debris Office, in an ESA press release. "Using this new technique, it will become possible to track previously 'invisible' objects that had been lurking in the blue skies, which means we can work all day with laser ranging to support collision avoidance." The new technique differs from conventional methods in that it can track objects during daylight hours, which it does using a combination of telescopes, light deflectors, and filters that track light at specific wavelengths. So even when the sky is bright and blue, scientists can increase a target's contrast, making previously invisible objects visible. Keys to this method include additional telescopes and the ability to visualize space debris against the blue sky background in real-time. In daylight tests, the distances to 40 different objects were measured with the new technique, which had never been done before.
Now other than dodge, duck, dip, dive and dodge (Score:3)
We could perhaps do something about collecting and removing said space junk.
There seems to be plenty of it, and de-orbiting or collecting it so there is no longer a threat would be a great next step.
Since all the work to get all that weight into space is already done, maybe someone could build an orbital recycling plant.
Re:Now other than dodge, duck, dip, dive and dodge (Score:4, Insightful)
This idea has been explored; the problem is the debris is whizzing around at insane speeds, and matching vectors and velocities is a non-trivial problem. Basically, you'd have to launch a massive vehicle with lots and lots of fuel, because it would be burning huge amounts just to catch up with the targets. Then you'd have to work out how to securely catch and store objects of wildly different compositions, masses and physical configurations.
https://www.researchgate.net/p... [researchgate.net]
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You don't really need to catch it, just slow it down enough to de-orbit in reasonable time. Some kind of sail like structure, or even a cloud of foam might work.
Re: Now other than dodge, duck, dip, dive and dodg (Score:1)
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We already know we can hit it with a laser from the ground. But if we could hit it with a powerful enough laser in space, from in front, perhaps we could slow it down enough to deorbit.
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... what?
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You don't really need to catch it, just slow it down enough to de-orbit in reasonable time. Some kind of sail like structure, or even a cloud of foam might work.
Slow it down? Um... Lower orbits are faster right?
Orbital mechanics are not readily apparent to many.. But let's suffice it to say that you need to apply enough delta V in the proper directions to get the object to enter the atmosphere. Sometimes, that is most efficiently done by adding energy, other times it's removing energy, usually the best approach is to change the orbit into one that at perigee is in the upper atmosphere.
But do understand that this is only a serious problem for objects above a spec
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The boosters for the Apollo landers still revisit Earth periodically, I think one was just re-located a couple years ago. That's a big chunk of mass that it seems someone could find a use for. Jeff Bezos' new summer cottage?
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Drat, turns out you're right. I knew the ones for the later missions were impacted on the lunar surface to give a signal for the siesmometers to read, didn't realize the others were in heliocentric orbit.
Next step: removal. (Score:4, Interesting)
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I think they could try to slow down the junk with well-aimed high-energy bursts to cause deceleration due to ablation.
So sniping space debris with explosives, and hope we don't send it flying in the direction we don't want it to go?
I know we have a garbage problem, but I sure hope this idea doesn't turn into the worlds worst pinball machine.
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How about doing it with lasers?
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How about doing it with lasers?
Only if they're attached to sharks. And cost one-meeeeeliion dollars each.
It's the only way. Otherwise, you'll shoot your eye out, kid.
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How about doing it with lasers?
Only if they're attached to sharks. And cost one-meeeeeliion dollars each.
Ok, but how do you expect to get the sharks into space and live long enough to target the debris with their lasers with a budget of only $1 million each? SpaceX isn't that cheap yet. Or are you hoping over the total duration of the project that the per sharkunit cost will average out to $1 million?
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How about doing it with lasers?
Only if they're attached to sharks. And cost one-meeeeeliion dollars each.
Ok, but how do you expect to get the sharks into space and live long enough to target the debris with their lasers with a budget of only $1 million each? SpaceX isn't that cheap yet. Or are you hoping over the total duration of the project that the per sharkunit cost will average out to $1 million?
That's cost per sharkunit. Additional fundraising provided during the LaserShark telethon, which will be hosted by President Yeezy, broadcast during shark week, and sponsored by NatGeo.
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Not trying to diminish their achievement (Score:2, Funny)
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I think it was a wordplay on the terrible phrasing of the title.
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The real question is, who the heck is arming space junk with lasers in the first place?
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Kessler syndrome (Score:5, Informative)
The Kessler syndrome (also called the Kessler effect, collisional cascading, or ablation cascade), proposed by NASA scientist Donald J. Kessler in 1978, is a theoretical scenario in which the density of objects in low Earth orbit (LEO) due to space pollution is high enough that collisions between objects could cause a cascade in which each collision generates space debris that increases the likelihood of further collisions. One implication is that the distribution of debris in orbit could render space activities and the use of satellites in specific orbital ranges difficult for many generations.
The Kessler syndrome is troublesome because of the domino effect and feedback runaway wherein impacts between objects of sizable mass spall off debris from the force of the collision. The fragments can then hit other objects, producing even more space debris: if a large enough collision or explosion were to occur, such as between a space station and a defunct satellite, or as the result of hostile actions in space, then the resulting debris cascade could make prospects for long-term viability of satellites in particular low Earth orbits extremely low. However, even a catastrophic Kessler scenario at LEO would pose minimal risk for launches continuing past LEO, or satellites travelling at medium Earth orbit (MEO) or geosynchronous orbit (GEO). The catastrophic scenarios predict an increase in the number of collisions per year, as opposed to a physically impassable barrier to space exploration that occurs in higher orbits.
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However, even a catastrophic Kessler scenario at LEO would pose minimal risk for launches continuing past LEO, or satellites travelling at medium Earth orbit (MEO) or geosynchronous orbit (GEO). The catastrophic scenarios predict an increase in the number of collisions per year, as opposed to a physically impassable barrier to space exploration that occurs in higher orbits.
Why is it that we assume that catastrophes at lower orbits, would simply not affect anything else getting through that orbit? Is it simply duration we're basing that on, along with merely crossing our fingers?
Seriously curious.
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True story - same topic but opposite direction
Many years ago I was responsible for the IT infrastructure running over many buildings and sites.
One afternoon a group of people stared digging the road up outside our main building - quite close to where the fibre bundles ran.
The building manager and I went out to chat to them. They were fixing a reported leak in a sewer pipe.
The conversation went:
"Please be careful digging here - there are power and communications cable running between buildings at about this
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Space is really, really big. Even if LEO was 'full' of junk, (which being in LEO would eventually de-orbit by itself), threading the needle to higher orbits would not be too hard, since most objects can be tracked. The very small ones would be a problem, however, so there would be an element of luck involved. (It's not the mass that does the damage, it's the relative speeds at which the objects are travelling) See:
https://www.theverge.com/2016/... [theverge.com]
Re: Kessler syndrome (Score:1)
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So the pessimist says "Space is half full" and the Optimist says "Space is Half empty"?
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The engineer says, "Space is half utilized."
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Duration would be the major asset, if you're going through LEO to a higher orbit you're only there for seconds to minutes. Even in the worst scenarios for Kessler Syndrome something would have to be in LEO for weeks before having a noticeable chance of being hit by anything injurious.
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If you're going to copy/paste something that large please add the source. We don't need SlashDot to get into legal issues.
Stars are visible in the daytime (Score:1)
Laser-o-rama (Score:2)
Find Objects by Shining a Light on Them (Score:1)
Dist (Score:2)
The lasers are used to determine distance, not to find or illuminate it. Iirc they can detrmine the distance to the moon to within 5 inches.
Don't look at my Junk (Score:2)
You can spot my junk with a laser in daylight? Not a technology I want.