Astronomers photograph exo-planet!

[Seeker]

Actually, if we found one, sending the people isn't as much of a problem as you'd think, if we just keep accelerating them, because of time dilation. We could probably achieve a relatavistic speed using a Project Orion-esque set-up.

Our intrepid explorers zoom off on a journey of many light years to a star with a watery planet and oxygen atmosphere...this journey only takes them a few years...but, d'oh, someone forget the donuts back home...where in the meantime 10 000s of years have gone by, human civilization has changed/moved/died/left a note reminding its descendants to put out the cat...

Time dilation really plays hob with the colonization/trade/cultural exhange of any potential GALACTIC EMPIRE. Maybe the could hack it if they were near-immortals? Hey bob, I know I've been away a while, any thing interesting happen in the last 50k? Oh, same old, same old....

This is why in science fiction there is always a space drive (usually called a 'hyper' or 'warp' drive) to fix this problem, allowing the GALACTIC EMPIRE to thrive and the Humans to finally crush those snivelling Mrrshans. Unfortunetly, the closest theoretical model we can come up with is the Modified Alcubierre Warp Drive(google it), which is amazing in that it is probably sortof theoretically workable, but it relies on large quantities of Unobtainium, such as negative mass matter.

[Vince278]

Originally posted by Bill3000
Technically, all bodies of all types that have a therodynamic temperature above absolute zero radiate.

Including black holes but you can't see those.

[Vince278]

Originally posted by Seeker
such as negative mass matter.

Like condensed dark energy?

[Urban Ranger]

Negative energy matter?

[Vince278]

Originally posted by Urban Ranger
Negative energy matter?

According to E=MC^2, energy and matter are equivalent. I suppose that applies to dark energy as well.

[DeathByTheSword]

the could see the planet because:

a) it is so freakin big
b) the star is very cold (only 1000 degrees on the surface) this is way is is mostly infrared so the light of the star didnt block the view...

[DeathByTheSword]

and oh yes it isnt a normal planet because it is actually a failed version of the star it is orbitting...it was just to little to become a star but it is not that is was formed of residue of the star it is orbitting

[Dry]

Originally posted by Az
my definition
A rock larger than some arbitrary size X with a nearly perfect spherical shape that emits no visible light.

I don't think it needs to be a rock.
I agree on the shape & light emission.
I'd add it needs to orbit oround a star, otherwise it's a moon.

[Bill3000]

It doesn't have to be... Double planets, for instance.

[reds4ever]

Pluto/Charon?

[BeBMan]

Originally posted by Dauphin
The Earth must turn off its lights at night, else its not a planet!

Is that a real pic - looks a bit cgi-ed ... still cool

[reds4ever]

yep, nice pic, but its defineatly been fiddled with

[Az]

I don't think it needs to be a rock.
I agree on the shape & light emission.
I'd add it needs to orbit oround a star, otherwise it's a moon.

Moons are planets, too. I agree that the "rock" part wasn't the correct thing to say.

oh yes it isnt a normal planet because it is actually a failed version of the star it is orbitting...it was just to little to become a star but it is not that is was formed of residue of the star it is orbitting

brown dwarves are planets, too.

[Kuciwalker]

Originally posted by Az

I don't think it needs to be a rock.
I agree on the shape & light emission.
I'd add it needs to orbit oround a star, otherwise it's a moon.

Moons are planets, too. I agree that the "rock" part wasn't the correct thing to say.

No they aren't. Add to the definition that the planet is the body that contains the center of mass of the system orbiting the star.

[Az]

It's a silly definition. If, for example, one would find a celestial body the size of earth, venus, or mars, drifting in space, not calling it a planet would be completely rediculous, IMHO.