1st August 2010, 5:48 AM
That said, planet "size" is rather irrelevant. Existence of water, distance from stars, and several other factors are of much higher consequence than size.
"Size is not at all irrelevant." The only working model we have that definitely supports life is a planet with an equatorial radius of 6,378.1k, equatorial circumference of 40,075k, surface area of 510 million k, mass of 5.9736 × 1024 kg, and surface gravity comparale to 0.99732 g. Now, I'm not at all suggesting that all the world's astronomers, physicists and engineers know more about what to look for than you do--chances are, they don't---BUT if they're seeking an Eath-sized-planet because we know that an Earth-sized-planet, based upon the above criteria is the only concrete example of a model than can support life... well I hate to contradict you, because you know so much about astrobiology, but I'm going to go ahead and give them the nod to continue.
Dr. EdenMaster, we all know that life may exist on worlds larger or smaller than the Earth. The fact remains that our only empirical model of Life is the Earth. I think it is totally logical to begin a search for life on Earth-sized planets.
Planets much larger will be almost inevitably gas giants. And even if these gas giants do have life, it'd almost certainly be of a type that we have never seen and could not readily identify.
Planets much smaller, almost certainly rocky and solid, may or may not have the mass and gravity to maintain an atmosphere... and furthermore, they'd be harder to find.
Earth-sized planets are the totally logical place to look.
"Size is not at all irrelevant." The only working model we have that definitely supports life is a planet with an equatorial radius of 6,378.1k, equatorial circumference of 40,075k, surface area of 510 million k, mass of 5.9736 × 1024 kg, and surface gravity comparale to 0.99732 g. Now, I'm not at all suggesting that all the world's astronomers, physicists and engineers know more about what to look for than you do--chances are, they don't---BUT if they're seeking an Eath-sized-planet because we know that an Earth-sized-planet, based upon the above criteria is the only concrete example of a model than can support life... well I hate to contradict you, because you know so much about astrobiology, but I'm going to go ahead and give them the nod to continue.
Dr. EdenMaster, we all know that life may exist on worlds larger or smaller than the Earth. The fact remains that our only empirical model of Life is the Earth. I think it is totally logical to begin a search for life on Earth-sized planets.
Planets much larger will be almost inevitably gas giants. And even if these gas giants do have life, it'd almost certainly be of a type that we have never seen and could not readily identify.
Planets much smaller, almost certainly rocky and solid, may or may not have the mass and gravity to maintain an atmosphere... and furthermore, they'd be harder to find.
Earth-sized planets are the totally logical place to look.
H.R.M. DARVNIVS MAXIMVS EX TENEBRIS EXIT REX DEVSQVE GORONORVMQVE TENDORVM ROMANORVM ET GRÆCORVM OMNIS SEMPER EST