CubeSAT to Alpha Centauri?

[EliteShadowLeo]

Too much science for me.

[architeuthis]

Just a quick question.

If we took a small CubeSat, and somehow gave it enough power to sustain itself for 100 years, could be throw it onto an SLS rocket and send it to Alpha Centauri, just like that?

You would need some special 3rd stage or have to do a gravity assist at Jupiter, and even then it would take tens or hundreds of thousands of years transit time to reach the Alpha Centauri. The solids boosters, core and upper stages together only give SLS about 18km/s of delta-v (assuming no payload). This is not enough delta-v to reach solar escape velocity from Earth's surface:/

[SuperBigD60]

I believe there's also research into the possibility of propellentless propulsion with some wierd kind of plasma engine. I only know because the KSP interstellar mod has an engine like that and justifies it by saying its sort of possible.

[TheDarkStar]

I believe there's also research into the possibility of propellentless propulsion with some wierd kind of plasma engine. I only know because the KSP interstellar mod has an engine like that and justifies it by saying its sort of possible.

Do you mean the Alcubierre drive (http://en.wikipedia.org/wiki/Alcubierre_drive)? That's the only reactionless drive in that mod.

[K^2]

What would be the point in this venture? Travelling at 0.04c & with no means of slowing down, you'd pass by Alpha Centurai A, then 2.5 days later you'd pass by Alpha Centurai B. 100 years of travelling to spend 60 hours within the system. I don't see the benefit.

I was going to suggest deploying a drogue. It might sound silly, but if you do the math, it can actually get you more than 10Pa of pressure as you are flying by a star at these speeds, which is a good amount of deceleration. Unfortunately, the probe is going to buzz by the region with any significant solar wind density so fast that the net effect is negligible.

Now, for a slightly larger probe, this is still an option. If you use a magnetic scoop instead of a drogue, you can get that incoming hydrogen to something like 1GK, which is more than enough for fusion. So you can organize a reverse bussard ramjet, which can provide significant braking even in interstellar space. But this isn't something that you can put on a 4kg 3U cubesat.

[SuperBigD60]

Do you mean the Alcubierre drive (http://en.wikipedia.org/wiki/Alcubierre_drive)? That's the only reactionless drive in that mod.

no, I meant the quantum vacuum drive or whatever its really called.

[K^2]

no, I meant the quantum vacuum drive or whatever its really called.

A real quantum thruster is effectively a photon drive. We have a discussion thread on it a bit bellow. There is simply no way to get the power generation capability required for this into a cubesat.

[SuperBigD60]

A real quantum thruster is effectively a photon drive. We have a discussion thread on it a bit bellow. There is simply no way to get the power generation capability required for this into a cubesat.

That could pose an interesting engineering problem.

Maybe the machines will figure it out once they take over

[jwenting]

Just a quick question.

If we took a small CubeSat, and somehow gave it enough power to sustain itself for 100 years, could be throw it onto an SLS rocket and send it to Alpha Centauri, just like that?

yes, you could do it. But it'd run out of power after a hundred years and then be just a very small hunk of metal, plastic, and silicon hurtling through space at a few thousands of meters per second on the way to a star light years away for the next several tens of thousands of years or longer.

If you have the money, be my guest. But it's not worth doing. No scientific or economic benefit whatsoever. And not even bragging rights. Not only will you be dead long before it gets there, but it won't even be able to send pictures back so your future descendants hundreds of generations later can point and say "see, your distant ancestor paid for that thing to be launched".