First habitable extrasolar planet discovered

Zakharra · Post by **Zakharra** » Thu May 10, 2007 1:43 pm

Vincent van ’t Hof wrote:A lot of interesting propulsion ideas here, except... where are the brakes?

That's simple. Turn the ship around and the thrust that propelled you is now acting as a brake.

Magonushi · Post by **Magonushi** » Thu May 10, 2007 5:30 pm

Charlie wrote:Now there's the question of running into floating detritus in space and getting swiss-cheesed. The front-shielding would need to be very very dense, and yet again.

In addition to the other critisms, you are aware that even a very small ship traveling at relativistic speeds will have to deflect several A-bombs worth of Kinetic Energy every second just from running into hydrogen atoms. Hit a patch of dust and we are talking Kinetic Energy equivalent to that required to nuke the entire surface of the earth.

Not even Zeus's Aegis could deflect that godly amount of energy.

Grand Fromage · Post by **Grand Fromage** » Thu May 10, 2007 9:10 pm

Vincent van ’t Hof wrote:A lot of interesting propulsion ideas here, except... where are the brakes?

Turn around halfway to the destination and the engine becomes the brake. :F

You would also want to swing around large objects and slow down with their gravity, then aerobrake at your destination planet. If it has an atmosphere.

hollyfant · Post by **hollyfant** » Fri May 11, 2007 9:14 am

Assuming we're talking about a cargo of living Humans, there's a limit to the acceleration/deceleration the ship can be subjected to. Using planets at the destination point to slow down requires the vessel to be going pretty slow already, or the required steering will be practically impossible.

Let's face it, generation ships are the only real option.

Mulu · Post by **Mulu** » Fri May 11, 2007 2:49 pm

I tend to agree. A generation ship is certainly the only thing we could make with current technology, or even reasonably foreseeable technology, though it may be possible with genetic engineering in the near future to be freezable and just wake up at the destination.

Charlie · Post by **Charlie** » Mon May 14, 2007 8:17 pm

The ammount of forward-energy produced is porportional to the speed of the vechicle. The mass of all components stay in balance.

Reletivity is an illustion, as is time. Time is your brain remembering what happened, as well as a preception of movement.

There is still, I agree, the issue of slowing down. Takes 8 min for light to reach the earth from the sun.

Deflection is a materials issue. I just build the probe, and the eggheads watch it burn up in the solarsystems outer belts. :p

NESchampion · Post by **NESchampion** » Mon May 14, 2007 9:33 pm

Charlie wrote:The ammount of forward-energy produced is porportional to the speed of the vechicle.

What the hell is "forward" energy? KE in the "forward" direction? Isn't it then given that KE is proportional to velocity? Say in an equation like KE = (1/2)mv^2?

There is still, I agree, the issue of slowing down. Takes 8 min for light to reach the earth from the sun.

What does the time it takes for light to reach Earth have to do with slowing down a spaceship?

Grand Fromage · Post by **Grand Fromage** » Mon May 14, 2007 9:41 pm

roofles, I love being proven right by my targets. :F

Post by **paazin** » Tue May 15, 2007 12:05 pm

Grand Fromage wrote:roofles, I love being proven right by my targets. :F

NickD · Post by **NickD** » Mon May 21, 2007 8:48 am

OMG! I was trying to look up some information on a sci fi show I saw a while back (involving some space fighter recruits who combat aliens that are afraid of dead bodies... that's most of what I remember about it... apart from I really liked the song in the pilot episode so I was trying to look up what it was...)

Anyway... I didn't find it. But I did find this!

http://en.wikipedia.org/wiki/Earth_2_%28TV_series%29

I only watched the first episode or two of it when it was on, but I remember it. "So what?" You ask. Well... look at this!

Desperate to save her son, Devon puts together an expeditionary project called the Eden Project, which intends to travel to an Earth-like planet called G889 in an attempt to find a cure for the illness. More than 200 other "Syndrome families" intend to follow Adair's advance party, joining them on the planet 22 light years away from Earth to form a colony called New Pacifica. The project, however, is opposed by the government and secretly monitored and infiltrated with agents.

And from the article in the first post of this thread.

The planet's name is Gliese 581 c.

[...]

The host star, Gliese 581, is among the 100 closest stars to us, located only 20.5 light-years away

Co-incidence? I think not! I smell a conspiracy!

Grand Fromage · Post by **Grand Fromage** » Mon May 21, 2007 9:13 am

I actually read a book for my sci-fi class that took place on a habitable world orbiting a red dwarf 20 light years away, and the planet was significantly larger than Earth. Clearly there's a conspiracy here.

Post by **paazin** » Mon May 21, 2007 12:08 pm

Grand Fromage wrote:...sci-fi class...

Wha...?

Grand Fromage · Post by **Grand Fromage** » Mon May 21, 2007 5:17 pm

paazin wrote:
Grand Fromage wrote:...sci-fi class...
Wha...?

Science fiction literary analysis. Sitting around talking about the political philosophy of Starship Troopers for credit. Oh yes, it was awesome.

mxlm · Post by **mxlm** » Mon May 21, 2007 7:53 pm

So how many 'Heinlein was a fascist!' comments were there?

Grand Fromage · Post by **Grand Fromage** » Mon May 21, 2007 8:20 pm

mxlm wrote:So how many 'Heinlein was a fascist!' comments were there?

None. It's surprising what people pick up on when they actually read the book.