Fwd: Planets and stuff

[Timothy Sennott]

Heyo all,

Just wrote this email b/c I was rambling about interstellar travel while camping this weekend. But thought y'all might enjoy it. 

James, correct me on anything if I've misspoken ;)

PS James lets hang out soon! Busy few weeks but maybe grab dinner up here one night on your way back from work? I can probably make it down to the south bay for a night sometime after thanksgiving too

PPS Hope everyone is doing great!

T

Tim Sennott

timothy...@gmail.com

tsen...@berkeley.edu

Skype: timsennott

Mobile: 508.330.3796

Begin forwarded message:

From: Timothy Sennott <timothy...@gmail.com>

Subject: Planets and stuff

Date: November 12, 2012 7:06:46 PM PST

To: Maddee Rubenson <ruben...@gmail.com>

Cc: Zac Rubenson <zrub...@gmail.com>

So, wanted to firm up my spaceflight numbers for the nature kiddies (and myself)

~0.97 years to reach light speed accelerating at a speed of 1 g (normal earth gravity). More realistic speed is about 50% speed of light, max, since relativity makes objects much much heavier past this speed. So 6 months to this speed. 

Closest planet is actually closer than I thought, 4.2 light years, but the next closest is 15 (though we may find more, planets are harder to find than stars). Closest stars are more common, 50 of them between 4 and 15 light years from us. 

So theoretically, we could visit a number of close planets within a human lifetime (barring new physics or worm holes or making warp drive). 

But even with theoretical nuclear fusion rockets using fuel mined from Jupiter that we don't have any idea how to make (we can't even do this on earth yet), you'd need more like 4 years to reach 12% of the speed of light, and then 30+ years or so to reach the closest star/planet. Or 120 years to get to the next closest planet. 

And even then, with this exotic nuclear fuel, 99% of your spaceship needs to be fuel just to get to 12% of the speed of light. Beyond this speed is impossible without something totally new. If you had a spaceship using antimatter as the fuel, and the entire spaceship was fuel, you could probably get to 75% of the speed of light I think. But that would take more energy than everything we've produced on this planet to date. 

Another more realistic project using existing tech (fission) proposed a 100 year trip to reach the nearest star. This would only be 90% fuel... 

Anyway, some fun facts for y'all

T

Tim Sennott

timothy...@gmail.com

tsen...@berkeley.edu

Skype: timsennott

Mobile: 508.330.3796