Kepler Spacecraft Discovers Twin Planets

    Astronomers using NASA's Kepler found two planets orbiting the sun and only 1.5 million miles from each other! To give you a perspective, Venus, the closest planet to earth, is 27 million miles away from earth along its orbital path.
    The smaller of the two planets is named Kepler-36b, has an estimated 30% iron mass, and is 4.5 times more massive (heavier) than Earth. The larger planed is dubbed Kepler-36c and is composed of mainly hydrogen and helium.
    Planets in orbit like this are unheard of, and have gotten scientists to revisit theories having to do with the formation of solar systems. It is largely accepted and understood that in the formation of a solar system, solid planets are able to form closer to the sun because their mass and gravity can retain what makes up the planet, where as gaseous planets form further away from the sun because the closer to the sun you get, the harder it is for the gas making up the planet to be retained.
    An explinations for this has to do with Kepler-36c having migrated over time into the orbit it is in now. Even more exciting to scientists is the possibility that they may be able to use this data to find the "sweet spot" where planets are able to retain a gaseous atmosphere like Earth's verses it being vaporized by the sun like on Venus.