This article about the Pioneer 10 spacecraft got me wondering. Assume that aliens launched a similar probe and that it’s traveling at the same speed (27,335 MPH). If the probe were to fly through our solar system today, would we realize it? And if we did, would there be any chance we could catch it?
We can’t keep people from crossing the Mexican/American border when we have people standing there looking for them. You want us to spot something the size of a person travelling through the solar system? Also, bear in mind that the majority of the solar system exists 'way out beyond the orbit of Mars, and, by non-Star-trek standards, that’s a huge amound of space.
I think it might be doable. It would be basically a cometary rendezvous, and if we had enough advance warning (say, if it were broadcasting), I think a mission could be set up to meet it.
Capture it, maybe not; any payload we sent up would be pretty darn small; but I don’t think it’s impossible to meet it & take some pictures.
Unless it was emitting something, I can’t see how we’d realize it.
Could we catch it? If there was enough advanced notice, a definite maybe but that would almost certainly depend on how fast it really is going.
Cripes…the alien satellite had better fly REALLY close by the earth for us to see it. There are tons of asteroids, meteors and such already out there. One teeny space probe likely would go completely unnoticed.
As for catching it I don’t think we could. However, if we knew it was there, knew it was alien and had enough time to prepare (unlikely) I’m sure we could manage to get something together to catch it. Certainly be worth the effort.
Finally, realize that 27,000 MPH is REALLY slow! Proxima Centauri is 4.22 light years (40 trillion kilometers) away and is the next closest star to us besides the sun. Our fastest space probe would take 300,000 years to get there (and Pioneer is not the fastest…I think Ulysses is but I’m not certain). It just gets worse form there so I wouldn’t hold your breath on this one.
It would be exceedingly unlikely. Even if it passed by close enough to earth to be seen and identified as an asteroid like object, it would probably take some time for its path to be calculated, and find that it was an interloper to the solar system. By this time, a Pioneer sized object would likely be out of range for further study, let alone any Rendezous with Rama style missions to the object, even with robot probes.
One interesting case is the discovery of a third stage Apollo booster in orbit around Earth, outside the orbit of the moon…
http://www.space.com/scienceastronomy/rocket_paint_020918.html
This object is larger than Pioneer by a few orders of magnitude, and in orbit around the Earth so it can be observed at the leisure of scientists.
The best way for such an object to be “visible” would be for it to be broadcasting a radio beacon out in all directions.
“Catching it” would be an interesting exercise I think, and would probably involve send a probe out to rendezous and attach to it, then using a booster to modify its path to put it in permanent Solar orbit for future study. I would guess that it will be many, many years before we have the capabilities to improvise such a mission on extreme short notice.
Cripes. Why didn’t Sagan and all those other yahoos who went through all the trouble to design the plaque, etc., give this some thought? How hard would it be to configure the thing to broadcast a beacon signal whenever the power from its solar panels allowed? That would give the aliens a fighting chance.
Who wants to be noticed? Didn’t anyone see the movie “Independence Day?” How about “V?” Or has anyone read “The Hitchickers Guide to the Galaxy?” Untill we are sure of how the aliens are going to behave, we ought to exercise our ears, and keep our mouths shut!
The Pioneer and Voyager spacecraft don’t have solar panels. They use RTGs - radioisotope thermoelectric generators, which is a lump of plutonium-238 which warms up one side of a thermocouple. The temperature difference is converted to electricity. The half-life of Pt-238 is about 90 years, so it would be useless in a few hundred years. In any case, the plaque is just a symbolic gesture. Nobody expects it to be found by aliens.
As for tracking and capturing a visiting spacecraft, it’s within our technological capability to launch a probe to rendezvous with it. If it’s small enough, it might even be possible to attach to it and slow it down. However even given an unlimited budget, I’d guess such a spacecraft would take at least 5 years to develop and build. You’d need a lot of advance warning to pull it off.
Read Arthur C. Clarke’s classic novel Rendezvous with Rama. It’s precisely about rendezvous with an alien space probe. In his novel, the earth has put in a “meteor watch” system to prevent Tunguska/“Armageddon” events, so there’s plenty of advance warning that allows the earth to put together a mission to rendezvous with the probe, which is on a hyperbolic orbit around the sun.
Yeah but Rama was one helluva lot larger than the Pioneer space probe. If a Rama sized object came through our solar system I sure as hell hope someone would notice!
In Clarke’s novel, Rama was not only big but spinning fast. So fast that if it were a natural comet or asteroid it shouldn’t be able to stay in one piece, which was why they decided to investigate it.