Exoplanets
Artists impression of an Exoplanet in a 2 star system (Source:NASA)
Exoplanets or extrasolar planets are planets detected outside our solar system. They can be detected and studied by ground based telescopes (ESO's VLT, Keck Obs) as well as space telescopes like the Hubble, Kepler, Spitzer, COROT, and MOST. Hopefully the James Webb Space Telescope will be making the scene in space around 2018. We are also finding new ways of investigating the atmospheres of these far away planets and their densities.
The Solar Nebular Disk Model... clouds collapse and form stars which then can give birth to planets. The formation of planetary systems is thought to be a natural result of star formation. The process is thought to take at least 100 million years.
Newly discovered, potentially habitable planets Kepler-62e and Kepler-62f ; the best candidates for habitable, earth-like planets we know.
The goal of course is to find Earth like planets within our Milky Way Galaxy...the closer the better! It is wise that we take the time to investigate exoplanets that are in our "cosmic neighborhood" before setting forth on a voyage that, even with better future technology that we'll develop, will take a very long time to complete.
We are just beginning to learn about these other worlds and other planetary systems. Kepler-22b is about 2.4 times the size of Earth and is considered a "Super-Earth". It is within the habitable zone in its planetary system, which means that it isn't too close or too far from its star. It takes 289.9 days to fly around its star (orbital period), which is very much like our sun.
Links --> Kepler 22 B video Alien Planetary Systems Exoplanet Videos Search For Earth-Like Planets
A Far Off Solar System Is Earth the galaxy's most prime piece of real estate? StarShade
Astrobiology/Exoplanets - Geoff Marcy Planets thrive in extreme environments
Planet rise - sort of an exotic full moon Olivier Guyon NGTS Debra Fischer: All About Exoplanets
Ancient Civilizations Astronomy Earth Mars Quotes Thinking Evolution