Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: bearnard1212 on 11/02/2021 09:49:00
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The consideration to keep in mind is called space junk, we got quite some trash up there in orbit of our planet. It's considered not to be a problem due that the size of the object would burn in our atmosphere. But we of Asgardia want to go to space and we require to keep in mind out of the prospect of security, what do we do about the space junk? And is there a possibility that space junk might be dangerous for Earth and its` population?
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The problem is not about it burning in the atmosphere since if it was in the atmosphere, it wouldn't be space junk. Thus very little of space junk poses a danger to Earth population since most of Earth's population is in said atmosphere where the space junk isn't. Some big pieces de-orbiting (Skylab for instance, also the Columbia) do pose a danger, but humans are remarkably small targets to hit, and the general influx of normal meteors poses a much larger threat, and even then it is incredible news when one of them actually manages to injure somebody.
So the problem is the threat posed by the stuff to non-junk satellites. There is almost nothing one can do about it unless we can invent some sort of tangential tractor beam, which is pure science fiction. The idea is to get these objects to actually hit the atmosphere instead of continuously missing it.
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The consideration to keep in mind is called space junk, we got quite some trash up there in orbit of our planet. It's considered not to be a problem due that the size of the object would burn in our atmosphere. But we of Asgardia want to go to space and we require to keep in mind out of the prospect of security, what do we do about the space junk? And is there a possibility that space junk might be dangerous for Earth and its` population?
My understanding of Asgardia is that they put some pieces of space junk into orbit with every bit as much rationality and scientific integrity as the people who went round sticking union jack flags into tropical islands a few hundred years ago.
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I had never heard of Asgardia...
Asgardia, also known as the Space Kingdom of Asgardia and "Asgardia the Space Nation", is a micronation formed by a group of people who have launched a satellite into Earth orbit. They refer to themselves as "Asgardians" and they have given their satellite the name "Asgardia-1".
https://en.wikipedia.org/wiki/Asgardia
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Asgardia as in "cover your..."? Or a misprint for the Irish police force? If the latter, no problem - they are very good at clearing the roads.
Space travellers have little to worry about. Most of the junk is in low earth orbit, and you won't want to hang about near home, surely?
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If you do not wish to allow the space junk to degrade in its orbit naturally and thus burn up of its own accord, you would have to decelerate/alter the orbit or the space junk, that would require alot of fuel. To get the fuel up there you would have to fire many more rockets up, or more probably a reusable space shuttle as you do not wish to create more space junk.
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The problem is not about it burning in the atmosphere since if it was in the atmosphere, it wouldn't be space junk. Thus very little of space junk poses a danger to Earth population since most of Earth's population is in said atmosphere where the space junk isn't. Some big pieces de-orbiting (Skylab for instance, also the Columbia) do pose a danger, but humans are remarkably small targets to hit, and the general influx of normal meteors poses a much larger threat, and even then it is incredible news when one of them actually manages to injure somebody.
So the problem is the threat posed by the stuff to non-junk satellites. There is almost nothing one can do about it unless we can invent some sort of tangential tractor beam, which is pure science fiction. The idea is to get these objects to actually hit the atmosphere instead of continuously missing it.
The largest problem about space junk is that it is dangerous for the spacecraft that can collide with this space junk and damage a space ship and put whole mission that can cost a fortune under thread. I know that some space comoany wants to make a mission which is about to clean this space debris somehow to avoid these colisions.
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The consideration to keep in mind is called space junk, we got quite some trash up there in orbit of our planet. It's considered not to be a problem due that the size of the object would burn in our atmosphere. But what do we need do about the space junk? And is there a possibility that space junk might be dangerous for Earth and its` population?
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I would look at it in a different way.....and propose a proof of concept experiment. We track the big pieces with radar. I would put a UV or x-ray laser in orbit, and see if we could ionize the junk object, and see what affect it had on it's orbit. I would not rely on any simulation or opinions. If that alone doesn't work, a magnetic field can decelerate the charged object. Space robot cowboys.
But even if we could remove the large junk, there is still a great problem, and that is all the "speck" junk. Perhaps a high powered x-ray emitter, to ionize, flying in a grid search fashion, might charge the specks.
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I would look at it in a different way.....and propose a proof of concept experiment. We track the big pieces with radar. I would put a UV or x-ray laser in orbit, and see if we could ionize the junk object, and see what affect it had on it's orbit. I would not rely on any simulation or opinions. If that alone doesn't work, a magnetic field can decelerate the charged object. Space robot cowboys.
But even if we could remove the large junk, there is still a great problem, and that is all the "speck" junk. Perhaps a high powered x-ray emitter, to ionize, flying in a grid search fashion, might charge the specks.
I found out that some space company is going to make so called cleaning mission that is about to clean Earth`s orbit from space junk. Cleanup represents the first step towards a clean space environment by being the first space debris removal dedicated mission.
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Although I appreciate the environmental issues raised by previous posters on this topic, I do quite like the thought that we've put all those satellites, and even bits of junk, into space.
It gives me a feeling of pride, in our human accomplishment. Does anyone else feel the same? I mean, looking up at the starry night sky, and seeing one of our artificial satellites travel quietly and routinely among the stars, and think:
"We did that"!
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Although I appreciate the environmental issues raised by previous posters on this topic, I do quite like the thought that we've put all those satellites, and even bits of junk, into space.
It gives me a feeling of pride, in our human accomplishment. Does anyone else feel the same? I mean, looking up at the starry night sky, and seeing one of our artificial satellites travel quietly and routinely among the stars, and think:
"We did that"!
Do you feel the same about this?
https://en.wikipedia.org/wiki/Great_Pacific_garbage_patch
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Although I appreciate the environmental issues raised by previous posters on this topic, I do quite like the thought that we've put all those satellites, and even bits of junk, into space.
It gives me a feeling of pride, in our human accomplishment. Does anyone else feel the same? I mean, looking up at the starry night sky, and seeing one of our artificial satellites travel quietly and routinely among the stars, and think:
"We did that"!
The big number of space items can cause to what is known as the ‘Kessler syndrome’, which represents a state where the object density is so high that it can cause collisions.
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Cleanup represents the first step towards a clean space environment by being the first space debris removal dedicated mission
The problem is that changing your orbit requires an enormous amount of fuel.
Such a mission can only hope to rendezvous with 1 piece of space junk and deorbit it.
It takes almost an entirely new mission to rendezvous with the next piece of junk (unless they are in a nice line, in a common orbital plane, like Starlink, geosynchronous or GPS satellites).
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The Clearspace-1 satellite, or ‘The Claw’, represents the first step towards a clean space environment by being the first space debris removal dedicated mission
The problem is that changing your orbit requires an enormous amount of fuel.
Such a mission can only hope to rendezvous with 1 piece of space junk and deorbit it.
It takes almost an entirely new mission to rendezvous with the next piece of junk (unless they are in a nice line, in a common orbital plane, like Starlink, geosynchronous or GPS satellites).
According to the information I found on the website of The satellite uses a pincer motion in order to capture the Vespa stage using its robotic arms. Following the seize of the rocket piece, the spacecraft and the captured object will re-enter the atmosphere and burn together. In order to successfully grab the debris item. As far as I know, GPS system is being still developed. (http://Spam[/url)
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The quickest way to get rid of the orbiting satellites, would be to start a global nuclear war. In such a war the combatant countries, America, Russia and China, would for military purposes, shoot down all the satellites.
Thus cleansing the sky of large chunks of material. Smaller bits would remain, and indeed be very abundant.
In the form of shattered debris from the military spy-satellites, GPS satellites, communication satellites, the Hubble Space Telescope, and so on, shot down during the war.
But these fragments would soon decay from orbit, and burn up as harmless meteors. Leaving the sky clean!
Is this a environmental argument for the benefits of immediate nuclear war?
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I think I'm getting infatuated BC
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The quickest way to get rid of the orbiting satellites, would be to start a global nuclear war. In such a war the combatant countries, America, Russia and China, would for military purposes, shoot down all the satellites.
Thus cleansing the sky of large chunks of material. Smaller bits would remain, and indeed be very abundant.
In the form of shattered debris from the military spy-satellites, GPS satellites, communication satellites, the Hubble Space Telescope, and so on, shot down during the war.
But these fragments would soon decay from orbit, and burn up as harmless meteors. Leaving the sky clean!
Is this a environmental argument for the benefits of immediate nuclear war?
Space junk include not only satellites. There are a lot of used parts of rockets and space shuttles Also, there are satellites and microsatellites that don`t work anymore and just hover in Earth`s orbit. I guess we need to use special technology that can clean our orbit from space debris
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A chance for profits, recycling satellites. Lot's and lot's of rare earth in them I guess. But mostly they burn up. You could make it a International law that once they've done 'their thing', they still should be able to push themselves to earth to burn. But with the new types of micro satellite's miniaturized to a extreme degree we might not even notice them. Well, maybe? The problem relates to the scale of them, doesn't it?
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The quickest way to get rid of the orbiting satellites, would be to start a global nuclear war.
This just reduces thousands of satellites in controlled orbits to millions of fragments in uncontrolled orbits. It would multiply the hazard a thousandfold.
On the plus side, said war would essentially remove the problem since no new satellites would go up and all the new junk up there won't bother anybody anymore.
In such a war the combatant countries, America, Russia and China, would for military purposes, shoot down all the satellites.
You can't shoot one down. At best you can blow it to bits, which just gets you a lot of bits. It's not like an airplane where the bits all fall to the ground when you 'shoot it down'. A few chunks will be in orbits that now intersect Earth, but most will not.
But these fragments would soon decay from orbit, and burn up as harmless meteors. Leaving the sky clean!
That would require their kinetic energy to go somewhere. How does that work? If it did, there wouldn't be a significant space junk problem in the first place.
Yes, there are tiny molecules of gas up there and the friction with them will bring down the lower satellites after many centuries, but most orbits are too high to wait for this process.
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A chance for profits, recycling satellites. Lot's and lot's of rare earth in them I guess. But mostly they burn up. You could make it a International law that once they've done 'their thing', they still should be able to push themselves to earth to burn. But with the new types of micro satellite's miniaturized to a extreme degree we might not even notice them. Well, maybe? The problem relates to the scale of them, doesn't it?
That is a good point. They should be able to push themselves to earth to burn. And that is a good idea that can be used for futher usage of sats and microsats that don`t have large term of longevity. But space junk it`s not just used sats, There are a lot of fragments and parts from rockets and space shuttles.
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If you go out on a dark, clear, night, and look up at the sky, sooner or later you'll see a "meteor". In the form of a thin streak of white light, briefly passing downwards through the sky.
These meteors have been observed since ancient times. The explanation for them, in ancient times, was that they were a purely terrestrial atmospheric phenomenon. Like a kind of weak form of lightning.
The true explanation didn't emerge until the 19th century. When they were recognised as particles of extra-terrestrial matter, plunging into the Earth's atmosphere. Getting heated up by atmospheric friction, which made the particles become incandescent. And so become visible as meteors. The particles were usually very small. Like grains of sand.
All this is well-known and obvious.
The question I'd like to ask is this: Why don't we see our modern skies streaked with showers of meteors caused by thousands of tiny particles from our decaying satellites and rockets?
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The question I'd like to ask is this: Why don't we see our modern skies streaked with showers of meteors caused by thousands of tiny particles from our decaying satellites and rockets?
Partly because they are
tiny
But also because there aren't many of them.
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I admire BC's sophistry in not answering the question
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And also because most of the space junk is in orbit around the earth, unlike the classic meteor showers which orbit the sun.
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I admire BC's sophistry in not answering the question
Is there something wrong with your computer or whatever?
Here's the answer I gave
The question I'd like to ask is this: Why don't we see our modern skies streaked with showers of meteors caused by thousands of tiny particles from our decaying satellites and rockets?
Partly because they are
tiny
But also because there aren't many of them.
Can you see it?
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And also because most of the space junk is in orbit around the earth, unlike the classic meteor showers which orbit the sun.
And that I think is the answer, alan. Most of our space junk comes from stuff in low Earth orbit. So when this weak LEO stuff decays from orbit, it isn't travelling fast enough to get really incandescent.. Not like classic solar-orbiting meteors, which hit our atmosphere at huge velocities, and burn up in a spectacular light-show..
How come you knew the answer, and BC didn't?
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it isn't travelling fast enough to get really incandescent..
Orbital speed for low Earth orbit is about 8 km/s
So, for example a 1 Kg lump of aluminium would carry 32 MJ of energy
The specific heat capacity of aluminium is about 0.9 J/g/K
So 1Kg heats up by about 1.1 K for each KJ of energy you add to it.
And with 32000 KJ of energy, (if nothing else happened) it would reach about 29000K
Roughly 5 times hotter than the surface of the Sun.
How come you knew the answer, and BC didn't?
Because it's the wrong answer.
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It's the right answer. Meteors are not in earth orbit. space junk mostly is. Now and again a bit falls to earth but, far from "nothing else", stuff happens en route, like low-temperature ablation because the orbit decays gradually whereas meteors plunge into the atmosphere in travel in pretty much a straight line and convert their kinetic energy to heat very quickly.
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The idea that 8 km/s isn't fast enough to induce incandescence is wrong.
The issue is that it's in the wrong direction.
The other big problem is that there aren't many of them.
Sure, there's a catalogue with 128 million entries, but most of them have been there for a while and will be there for decades or centuries, so the number that fall in a given year is small.
And, of course, small things are more affected by the thin "atmosphere" up there but, as you say, they are gradually brought to a halt, so the effect isn't spectacular.
Only the big bits could hope to give us a firework display, and those are rare.
But we do see them sometimes
https://futurism.com/the-byte/footage-nasa-satellite-burning-up-reentry#:~:text=A%20NASA%20satellite%20that%20launched,spotters%2C%20as%20reported%20by%20CNET.
So the the answer to this question
The question I'd like to ask is this: Why don't we see our modern skies streaked with showers of meteors caused by thousands of tiny particles from our decaying satellites and rockets?
Is that we do see them.
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The idea that 8 km/s isn't fast enough to induce incandescence is wrong.
Which is why nobody suggested it.
small things are more affected by the thin "atmosphere" up there
Depends on the density of the thing. A steel bolt has loads of kinetic energy and very little drag, whereas a spent first rocket stage is huge (lots of aerodynamic drag) and relatively light, so quickly slowed down and deorbited by the wispy fringe of the atmosphere.
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The idea that 8 km/s isn't fast enough to induce incandescence is wrong.
Which is why nobody suggested it.
small things are more affected by the thin "atmosphere" up there
Depends on the density of the thing. A steel bolt has loads of kinetic energy and very little drag, whereas a spent first rocket stage is huge (lots of aerodynamic drag) and relatively light, so quickly slowed down and deorbited by the wispy fringe of the atmosphere.
The density of the space junk is very high, so that is why space companies are afraid of their space crafts can be damaged by these space junk on the Earth's orbit
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I think the main problem is tracking the small, high density bits. Rocket casings and suchlike will have a big radar profile and one of Buzz Aldrin's gloves (if it hasn't burned up yet) won't do a lot of damage, but a 2 x 1/4 (note the US dimensions) nut and bolt travelling at 8 km/s has 5 times the kinetic energy of a rifle bullet.
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Which is why nobody suggested it.
It seems a little harsh to call Charles a nobody.
So when this weak LEO stuff decays from orbit, it isn't travelling fast enough to get really incandescent
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small things are more affected by the thin "atmosphere" up there
Depends on the density of the thing. A steel bolt has loads of kinetic energy and very little drag,
Would a small bolt be affected more than a big bolt... you know... like I said?
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As with most aerodynamics, it's all about form factors. A small bolt will have a larger surface to mass ratio than a large bolt of the same general design, so will ablate more rapidly in the upper atmosphere, and a deorbiting cargo door (a friend had one fly open on his 757 freighter recently, and the DC10 was wont to shed the shed from time to time) may either burn up or float relatively gently to earth depending on its initial angle of attack, whereas most of a large bolt may survive the trip and impact at very high speed, like a metallic meteorite.