Two planets orbiting a distant star represent the first Earth-sized planets to be discovered at a distance from the host sun that allows them to be warm enough to sustain liquid water, an essential element to support life.
The NASA-led project, involving a Beaver Falls native and 2003 graduate of Penn State Erie, discovered five planets orbiting the star Kepler-62 that lies 1,000 light-years from Earth. One of those planets is 1.6 times the size of Earth and another is 1.4 times Earth’s size.
Planets as large as three times the size of Earth are terrestrial, or made of rock. Larger planets typically comprise gases or a combination of gases and rock, which would not support life, said Justin R. Crepp, now an assistant professor of physics the University of Notre Dame.
While Earth-like planets within the habitable zone represent the holy grail of astronomy, technology in development will be necessary to determine whether the two planets contain oxygen, carbon dioxide, methane or water — all elements necessary for life.