Re:Model predicts we're the only advanced civilization in th...
by goatlover on Monday June 25, 2018 @11:47AM
(#17393307)
But it only takes one advanced civilization to do it. And we're probably only a century away from being able to spam the entire galaxy with probes, if we wanted to say take apart Mercury and use solar panels for propulsion. The probes would be small, smart and able to replicate themselves.
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Re:Model predicts we're the only advanced civilization in th...
by vkou on Monday June 25, 2018 @12:19PM
(#17393587)
> And we're probably only a century away from being able to spam the entire galaxy with probes, if we wanted to say take apart Mercury and use solar panels for propulsion. The probes would be small, smart and able to replicate themselves.
1. We're really not.
2. Solar panels obey the inverse square law. Right now, we can't even use solar panels to power probes beyond the orbit of Jupiter - let alone drive an energy-hungry ion engine.
3. Even with an ion engine, you need fuel to thrust.
4. Even if we could send them, they'd need incredibly power-hungry antennas to transmit any useful data back. See 2.
People say things like 'only 1% of c' as if it's trivial. It's only 1%! It's also 3,000 km/s. No man-made machine has ever gone faster then 16 km/s. If we tried really hard, we might hit 1% of 1% of C.
And then it would still take that probe 400 years to visit our nearest star. 10 million years to cross the galaxy.
Re:Model predicts we're the only advanced civilization in th...
by sdenton4 on Monday June 25, 2018 @12:31PM
(#17393673)
...And then at the end of the trip, you've got to slow back down to 0% of c, if you want to do anything useful...
Re:Model predicts we're the only advanced civilization in th...
by vkou on Monday June 25, 2018 @12:34PM
(#17393691)
I find doubling your delta-v requirements to be far simpler then increasing them a hundred-fold. If we could get something to 1% of c, we could, with a bit more work, slow it down the same way.
We can't, though.