Extrasolar planets

[Chuchichastli]

I find the concept of a Dyson Sphere preposterous. We're talking something of the order of trillions upon trillions of cubic kilometres of building materials required to build the thinnest, most delicate habitable shell 93 million miles from the sun. The surface area would be something like 4 x 3.142 x 145,000,000 x 145,000,000 = 2.64 x10 to the power 17 square kilometres. An astronomical number! It's 40 million square kilometres for every man, woman and child on earth. A country well over twice the size of Russia or nearly five times the size of the USA! Each! I think it would be actually easier to simply build a planet from scratch.

Or am I misunderstanding what a Dyson Sphere is?

[Trapper]

I have to agree Chuchichastli.

I think it would be potentially easier to drag Titan, Mercury, and Venus to orbits we preferred. This could even solve the problem of Sol's future transitions of state.

This thread is getting pretty out there. Not that I'm complaining. I love this stuff.

nb the reason I advocated sending ships to other spiral arms is the risk of a hypernova in our vicinity.

[Sandgorgon rider]

I did some quick calculations about what you would need for a Dyson sphere. Assuming you want a sphere 93,000,000 miles (150,000,000 kilometers) in radius and say 10 meters thick this would give you a volume of 2.8X10^15th cubic kilometers. If you were to build it out of aluminum (density 2700 kg per cubic meter) this would require a mass of about 7.6X10^27 kg of aluminum. The mass of the Earth is about 6x10^24th kg, so you would need the equivalent of 1272 Earths worth of Aluminum or approximately the mass of 4 Jupiters.

It would be much easier to terraform planets, but of course you get much more living space with a Dyson sphere. There is of course the problem of the sun going Nova, use lots of sunscreen?

[Avatar]

Haha...very interesting posts folks.

Trapper...you talking about...trojan points???...or something there? (Re-orbiting nearby bodies) Sounds familiar somehow.

I think that sub-light colony ships is not such a far-fetched idea really. As we well know, the concept is already pretty entrenched in human understanding...it would surprise me more if it wasn't attempted by somebody.

--A

[Trapper]

I wasn't talking about Trojan points, Av. I must admit my understanding of that area of physics is lamentably poor. Actually my understanding of most things is poor...

The L3 Lagrange point might be a start, eg moving Venus to a mirror-image orbit around the sun relative to ours. Hopefully it would cool down a bit.

I was just saying that those bodies aren't doing us much good where they are.

I agree with you about interstellar travel. It's centuries off at best, but even at a snails pace I think it's something we should eventually try. It would be more fun than destroying ourselves, anyway.

[Avatar]

Haha, no, it's my lametable ignorance in the field...I didn't mean trojan points, I meant Lagrange points. My mistake.

--A