Asteroid detecting "net"

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(skip this paragraph to get to the idea)
Asteroids are a major threat to life on earth, we all know this which is why many scientists are trying to come up with a way to prevent any catastrophic asteroid impacts. The problem is that we need to detect asteroids in orders to deal with them, but we can only track them, and we all know that tracking them is far from a perfect art.

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So my idea is to create a network of satellites in a very high orbit, as high an orbit as we can get, in a geocentric orbit so that is makes a backyball like pattern of satellites around the earth.
These satellites would have infrared sensors that would allow us to detect any asteroids coming near earth that we missed, as well as allowing us to determine their size, velocity, location, and, with the help of additional sensors, the makeup of the asteroid. This would allow us to launch last minute countermeasures to help neutralize the asteroid, or at the very least minimize the damage it would cause.

Please comment with your opinions on this proposed system.

Geocentric orbits are equatorial - they would not form a "Buckyball" network. Even a 24-hour polar orbit would have the satellite crossing the South Pole 12 hours after it crossed the North Pole.

Also if the satellites were in a very high orbit they wouldn't be geocentric. It would probably be possible to track asteroids with a smaller number of satellites or from Earth. It should be possible to spot them 20 or 30 years before impact, at least if they're in a roughly circular orbit about the sun.

Comets are less predictable due to their elliptical orbits. We may get one that hasn't been near the sun for centuries. Comets are large and bright so it would be easy to stop. Perhaps the worst and most improbable danger would be from the asteroid belt. If one asteroid crossed another's path, it could change it's orbit and send it towards Earth in a few months and in a way that would be difficult to spot via telescope.

It doesn't necessarily need to be geocentric, thank you for correcting me, it just needs to be in the "Buckyball" pattern.



First, not all asteroids have circular orbits, many have elliptical ones. Second, not all comets are large. Third, they're only bright when they get close to the sun. And finally, I don't understand why a comet would be easier to stop than an asteroid.



That is exactly why we need a system like this, the Chelyabinsk meteor was undetected before it entered the atmosphere, we know that there are many, many, asteroids that we don't know of and therefore unprepared for.

Not possible. Even the GPS satellites do not have orbits that form a "Buckyball". Even if a constellation of satellites initially forms a "Buckyball" pattern, the pattern would change almost immediately, as the satellites travel along their elliptical orbits. Satellites in orbit don't stay in one place.

Remember, satellites in Earth orbit travel around the Earth's center of mass, and not it's axis of rotation.

Yes but any comet that's about to strike Earth would be close to the sun. We would see it.What's supposed to hold the ones above the polls aloft? If they're stationary they're not really in orbit.

There wouldn't need to be ones above the poles


Do you think it would work if all the satellite network would need to do is be able to have a line of sight with two others in the network to detect the asteroids passing between them through the "net"?

Sure ... but even if the satellites are in orbits that are 42,164 km (26,199 mi) in radius, at a speed of 20,000 km per second, there would be only about 2 seconds in which to give warning - just enough time for the people on the ground to realize they were about to die.

Well, I guess we're screwed. If not now then eventually.

No. The "Buckyball" satellite idea is just a bad one. It's the real-universe physics that make it impossible. An asteroid crossing the Moon's orbit at 20,000 km per second would take about 19 seconds to reach the Earth. How well prepared for impact would anyone be in that little time? How far can you run in 19 seconds?

That's why we have telescopes searching for asteroids that threaten Earth years in advance. Over just a few days of observations, its trajectory can be plotted over many decades. This may give us enough time to try to do something about it before the impact occurs.

In terms of asteroid collisions, "last minute" would probably be at least twenty or thirty years in advance.

In terms of what you probably mean by "last minute", if you waited until the last minute, it would be going so fast that you could not intercept it unless you were impossibly lucky. Those asteroids are not moving slowly.

Furthermore, I'm not sure what you could do about it. If it's that bad and you did reach it, what do you think you would do? Blow it up? All that would accomplish would be to vastly increase the number of pieces and the damage done when it enters the atmosphere.

If you were to accomplish something, you would need to nudge its orbit years before.

I think that you mean "geostationary". Not "geocentric".

so much to worry about..

as far as i can determine, the maximum "earth orbit" intersection speed for any object that originated from within the solar system would be about 650 km/s.
there is a class of comets called "sungrazers" that can attain close to this speed at periphelion, but they generally last for one or 2 orbits before they fully vaporize. their solar orbit is extremely elliptical (periphelion of about 120000 km and aphelion between 150-200 AU). any faster than this speed would result in the object escaping the solar system on it's departure trajectory from the periphelion.
maybe i am wrong, but i can not see how.

It would be better to just place a ring of detector sattelites around the sun, at the same orbit as the earth; any astroid that might ever impact the earth needs to cross earth's orbit, and therefor this 'circle'.

OP's idea is, as stated before, neither feasable (the proposed formation is just not possible), nor useful (we'd only get a few minutes warning).

The only way to make this 'last-minute intervention' work is if the sattelites themselves are armed (small enough astroid chunks will burn up in the atmosphere without damage, that's true), but having weapons in space isn't really a great idea...