ASAT Warfare

[Kerbin Dallas Multipass]

On one hand we have ASAT weapons http://en.wikipedia.org/wiki/Anti-satellite_weapon

Note the relatively recent proof-of-concept missions by China and USA.

On the other hand whe have the Kessler syndrome http://en.wikipedia.org/wiki/Kessler_syndrome

We know from the cold war that things occasionally got pretty hot. For example when the Russians shot down a US U2 spyplane. There were numerous incidents of airspace provocations between the superpowers, sometimes causing a certain trigger happiness with tragic results http://en.wikipedia.org/wiki/Korean_Air_Lines_Flight_007

It appears that countries do not wish to be spied on from above by their enemy in a cold war situation.

Let's just hypothetically assume that we see tensions rise between two space powers sometime in the next decade or two. Do you think we will see ASAT skirmishes?

Why am I asking this?

The general public and the media did not take much notice of the most recent missions listed in the wiki article. I don't think anyone is aware of the Kessler syndrome and nobody really wants to know the mid-term effects of an ASAT skirmish. Blowing up several dozens of satellites might render manned and unmanned spaceflight in certain orbits impossible or terribly expensive - For generations. It would throw our communication/navigation networks back to where they were in the late 70s. But ask any John Doe on the street and he'll be in favor of blowing up **** at no cost of human lives.

[Vaebn]

In a war situation, totally.

In a non-war situation, shooting down other people's satellites is not polite. Big explosions in space sending space garbage inducing trails everywhere is too visible an action to ignore.

More likely there is/will be a satellite cold war then where satellites would be disabled in "softer", deniable ways. Ie:

Lasers! Not to destroy (that's -probably- still pretty hard), but to, ie, blind the cameras on spy satellites.

Haxxors! Like trying to intercept/spoof commands to a satellite to waste all its attitude control. But which a government can always pretend "that's totally not us, it's terrorists with rasberris pi's or something".

Edited November 12, 2013 by Vaebn

[jwenting]

The Soviets have operational ASAT weapons. The US used to have but retired them when they retired the only aircraft that could operate them (a few modified F-15As) and thus had no way to use them (and by the time their solid rocket motors were becoming questionable anyway).

During the decades they've existed none have (been reported to have) been used except in pre-announced tests against derelict satellites or purposely launched targets.

And oh, Gary Powers' U-2 was far from the only US aircraft shot down over the USSR. The very reason the U-2 was developed was the increasing losses of its predecessors to Soviet fighter attacks.

[Nibb31]

The US has modified SM-3 missiles that can be fired from an Aegis cruiser to shoot down satellites, but missiles are really too messy to be used effectively as ASAT weapons. They can cause too much collateral damage.

Your best bet as an ASAT weapon is some sort of small orbital manoeuvering platform equipped with non-destructive weapons. Which incidentally, seems to be akin to what the MiTEx experiments were about. They could be prepositioned at strategic inclinations with enough dV to rendez-vous with their targets close enough to use their weapons.

As for the weapons, you would haver either:

- A high power laser that could burn a whole through the enemy sat's propellant tanks: The gas venting through the hole would put the target into an uncontrollable spin and deplete the propellant.

- A paint ball pellet gun or a black goo spray gun. These would mess up the optics and sensors and disable the solar panels of course, but black paint would also cause the components to overheat and fail.

Edited November 12, 2013 by Nibb31

[jwenting]

hmm, I seriously doubt an SM3-ER can reach that high... They can and have intercepted ballistic missiles in boost phase, but that's about it.

The one time it was used was against a deorbiting satellite at under 250km up, not a normal orbit for an ASAT target.

While a capable weapon, that under ideal launch conditions might be able to hit something in extremely LEO, it's certainly not a primary ASAT weapon.

[magnemoe]

hmm, I seriously doubt an SM3-ER can reach that high... They can and have intercepted ballistic missiles in boost phase, but that's about it.

The one time it was used was against a deorbiting satellite at under 250km up, not a normal orbit for an ASAT target.

While a capable weapon, that under ideal launch conditions might be able to hit something in extremely LEO, it's certainly not a primary ASAT weapon.

Not sure how high SM3 can reach but I guess maximum Ap is higher than 250km.

Main benefit of using it against an decaying satellite is that it don't leave any junk in orbit.

I don't see how missiles will cause more junk than a orbital asat weapon, the Russian and Chinese orbital asat is basically an small satellite with something like an claymore mine you point against target, setting it off will blow up the weapon platform and send the pellets towards the target.

The missile is one warhead, and its suborbital so all its fragments will fall down.

The target will be junk with lots of separate pieces in both cases.

[Seret]

Do you think we will see ASAT skirmishes?

Absolutely. Satellites are very high value C4I targets. That puts them high on the target list early in any war. If you have the ability to pluck out the other side's eyes, you do it.

[magnemoe]

Absolutely. Satellites are very high value C4I targets. That puts them high on the target list early in any war. If you have the ability to pluck out the other side's eyes, you do it.

However it require an war between two major countries, at least today, in the future asat capabilities will become more common.

S-400 might get asat capabilities like SM3 as the newest version has ABM capabilities so plenty of countries will get some asat capacity.

[Kryten]

A satellite low enough to be hit by something like S-400 or SM-3 is doomed anyway.

[jwenting]

Not sure how high SM3 can reach but I guess maximum Ap is higher than 250km.

Main benefit of using it against an decaying satellite is that it don't leave any junk in orbit.

they used it against a decaying sat because that sat was threatening to dump a load of hydrazine over populated areas when it came down (though there are doubts as to whether that tank would have survived reentry), and because it was the only thing they could reach and they wanted to show off after the Chinese destroyed a satellite in orbit (and a much higher orbit).

If they could have hit something that showed the system had real military value as an ASAT they would have, as is they just showed their lack of current capability.

[jwenting]

A satellite low enough to be hit by something like S-400 or SM-3 is doomed anyway.

Correct, and even then you need to get very lucky and/or spend a very long time positioning your launch system to take potshots at it.

No military value, but nice for propaganda to your civilians who don't know that you spent 2 months preparing to shoot something down that a week later would have crashed on its own while that real target is safely out of reach and spying on you, sending the location of all your units to your opponents in real time.

[magnemoe]

Correct, and even then you need to get very lucky and/or spend a very long time positioning your launch system to take potshots at it.

No military value, but nice for propaganda to your civilians who don't know that you spent 2 months preparing to shoot something down that a week later would have crashed on its own while that real target is safely out of reach and spying on you, sending the location of all your units to your opponents in real time.

On the other hand an satelite based asat weapon like the Chinese or old Russian require an satellite launch. Hit the rocket on pad or simply the wab with an cruise missile to disable the asat system.

The old US system with the F15 as first stage was also ballistic, if you wanted an asat weapon make an larger first stage on the SM3, you could not shoot it from the vertical launch system silo but you could live with that for the few launches you might need.

[Tommygun]

The US and Russia have already had a "satellite war" that isn't really talked about.

A number of years ago the Russian military fired a laser weapon at a number of US satellites.

They were ether destroyed of damaged. The US retaliated by hacking into the telemetry of at least one Russian satellites and ordering it to use all it's on board propellent to spin out of control.

These things happen, but you don't hear about them until ten or fifteen years later.

Unless there is an all out war between two countries, using missiles is too provocative.

It's more likely that they will use less conventional means I mentioned above.

Edited November 13, 2013 by Tommygun

[Nibb31]

A number of years ago the Russian military fired a laser weapon at a number of US satellites.

They were ether destroyed of damaged. The US retaliated by hacking into the telemetry of at least one Russian satellites and ordering it to use all it's on board propellent to spin out of control.

[Citation needed]

Edited November 13, 2013 by Nibb31

[lajoswinkler]

I never understood the logic behind this. It's like dropping an atomic bomb onto enemy target a kilometre away. Both parties suffer damage. If you crap up an orbital layer, nobody benefits from it. But I guess that's how it goes with military and logic. They just don't go together.

[Idobox]

In case of a war between two major powers, the ability to send scientific missions in 10 years counts less than the ability to move troops or fire ICBM without the ennemy knowing. You don't care about Kessler syndrome when you fear you country might be turned into a nuclear wasteland.

It's like dropping an atomic bomb on the whole enemy navy 1km from one of your bases: you're going to suffer losses, but they're worth it.

Russia, USA and France (and maybe others) have small rockets that can be launched from jet fighters (bombers?). They can be used to replace satellites downed by the enemy, and probably as ASAT too.

[Nibb31]

You don't need to blow up a sat to disable it. Modern ASAT solutions (as described in my previous post) don't cause debris.

[UltraVires]

Well, I couldn't find the Citation Nibb31 wanted, but I do remember the Incident that Tommygun is referring to. Happened during the 90's I think...

I did find this tho, with a quick google search http://news.discovery.com/space/history-of-space/satellites-cold-war-hacking-china.htm

This article refers to China's ability to perform Anti-Satellite operations, which has come about in the last 10-20 years, including the fact that they may already be messing with NASA orbital missions.

I even heard a Conspiracy theory that the loss of the Mars Observer Spacecraft was because the Chinese destroyed it with one of their own probes. I can't confirm that though...

There are several countries on Earth now with the capability of attacking and destroying targets in space. Seems space is about to be a pretty busy place...

Edited November 13, 2013 by UltraVires

[Kryten]

[Citation needed]

The Soviets did have an anti-satellite laser the 'Terra-3' complex, though only one designed to 'dazzle' optical spysats over their territory-I'd imagine what this is describing, after maybe half a dozen exaggerated retelling.

You don't need to blow up a sat to disable it. Modern ASAT solutions (as described in my previous post) don't cause debris.

Those aren't 'modern' solutions, those are future projects. Anything approaching an operational weapon system works on the good old-fashioned KKV technique-the only recent innovation in the field is China demonstrating that GEO sats are in reach with their 'Kunpeng-7' launch.

I even heard a Conspiracy theory that the loss of the Mars Observer Spacecraft was because the Chinese destroyed it with one of their own probes. I can't confirm that though...

And with good reason. The Chinese have never put anything on a trans-mars trajectory, as verified by anybody with space-tracking radar (e.g. USTRATCOM). If they did, they'd get a lot more out of having their own probe than blowing up somebody elses. It's not like blowing up interplanetary probes is something that's likely to ever really be militarily useful.

[ravener]

If you launch your asat weapon, say, a few dozen bricks with orbital manouvering capabilities, AGAINST the rotation of the earth. When the satelites connect with your orbital wall, could the loss of velocity be enough to make a satelite re enter? How far up, if anywhere, could you do this? What posibilities are there to forcibly decomission geostationary satelites without the debris staying in orbit?

[drakesdoom]

Most military targets in space are on very low orbits to minimize pass time and allow for greater image quality, any debris from them being shot down will have reentered in less than a year.

I would be more concerned about kessler syndrome starting if a GEO sat failed to move to a parking or disposal orbit and caused a crash.

[Warhorse]

If you launch your asat weapon, say, a few dozen bricks with orbital manouvering capabilities, AGAINST the rotation of the earth. When the satelites connect with your orbital wall, could the loss of velocity be enough to make a satelite re enter? How far up, if anywhere, could you do this? What posibilities are there to forcibly decomission geostationary satelites without the debris staying in orbit?

One of the quiet nightmares for NATO planners during the cold war was the realization that just about all the satellites in GEO belonged to the western powers --- the Soviets tended not to use that orbit, since much of the USSR is too far north to be seen from GEO. It was posited that the Soviets could launch an ASAT mission atop a large booster, and use a lunar swing-by maneuver to place it in a retrograde orbit at geosych altitude. Detonating the warhead would then create a cloud of debris moving in the opposite direction to most of NATO's commsats, thereby taking out a dismayingly large portion of their communications in one fell swoop ... :-(

[magnemoe]

If you launch your asat weapon, say, a few dozen bricks with orbital manouvering capabilities, AGAINST the rotation of the earth. When the satelites connect with your orbital wall, could the loss of velocity be enough to make a satelite re enter? How far up, if anywhere, could you do this? What posibilities are there to forcibly decomission geostationary satelites without the debris staying in orbit?

Try it in KSP, intercept speeds get very high, far higher than intercepting with an ballistic missile, so you get the worst of two worlds: you need to launch something to orbit and at the same time deal with intercept speed faster than in an ABM system. Its not that you need an anti tank weapon to kill a satellite.

[Bacterius]

If you launch your asat weapon, say, a few dozen bricks with orbital manouvering capabilities, AGAINST the rotation of the earth. When the satelites connect with your orbital wall, could the loss of velocity be enough to make a satelite re enter? How far up, if anywhere, could you do this? What posibilities are there to forcibly decomission geostationary satelites without the debris staying in orbit?

Unless I've misunderstood what you describe, there won't be much left of the satellite after it "connects" with the orbital wall. But a couple debris might deorbit, with some luck...

[falofonos]

Steel needles in a shotgun shell would do more than enough damage if launched to the right altitude, with a little planning you can knock out pretty much anything in a given orbit. It's not a case of pushing the satellite out of orbit, it's just a matter of hitting it with enough energy to vaporize important components.

geostationary orbital speed is 3.1 km/s, if you put your kinetic kill cloud in a retrograde orbit at the same altitude the combined impact velocity of 6.2 km/s gives you an impact energy of 19.2 megajoules / kilo.

You don't have to limit yourself to the retrograde orbit, of course, but if you want to kill all geostationary sats then it would be the way to go.

There are treaties prohibiting the westernization of space but it's a fair bet that all the major space powers have some orbital asat capability up there.