Earth-Like Planets May Be Very Common
18 February 2008
NASA's Spitzer Space Telescope is able to detect the infrared wavelengths from dust around other stars. NASA is saying they have detected 'warm' dust that is between -280 F and 80 F. From this information they are concluding that many stars have a region that is able to sustain the formation of planets like earth. Now the only problem they have is that planets can not form by themselves.
"From those observations of dust, we infer the presence of colliding larger rocky bodies, not unlike asteroids and other things in our solar system that we know bang together and generate dust," Meyer told reporters here at the annual meeting of the American Association for the Advancement of Science (AAAS). "By tracing that dust, we trace these dynamical processes that we think led to the formation of the terrestrial planets in our solar system."
In short, if there is dust there is rocks and rocks make planets.
Any object with mass produces its own gravity and affects any object that comes within its sphere of influence. If two objects are traveling at the exact same speed in the exact same direction in a zero gravity environment their own gravity may pull them together. If this happens with rocks enough times you will eventually get a object composed of many smaller rocks until their gravity becomes so strong that it can pull the object into a planet. The problem is that gravity is one of the weakest forces in nature. Every day you are able to supersede the gravity produced by 260,000,000,000 cubic mile planet by simply standing up.
Problems with planet formation:
1. Any rocks held together by their own gravity would not get larger, but be blasted apart by any other impacting objects.
2. Gravitational attraction would form a non spinning planet, unlike all the planets we observe.
3. Any static bond of dust sized particles would easily be overcome by the kinetic energy of a colliding particle.
4. Where did the first rocks come from? If planets are made of rocks and rocks made planets, what came first? How did rocks evolve from gases in space?
http://www.foxnews.com/story/0,2933,331107,00.html
