Researchers have found an Earth-sized planet outside of our solar system, and they think it has a rocky composition.
Kepler-78b is most likely not suitable for life as we could understand it because it is blazing hot, a NASA news release reported. The planet makes a speedy rotation around its host star every eight and a half hours.
"The news arrived in grand style with the message: 'Kepler-10b has a baby brother,'" Natalie Batalha, Kepler mission scientist at NASA's Ames Research Center, said. "The message expresses the joy of knowing that Kepler's family of exoplanets is growing. It also speaks of progress. The Doppler teams are attaining higher precision, measuring masses of smaller planets at each turn. This bodes well for the broader goal of one day finding evidence of life beyond Earth."
The planet was discovered using the well-known Kepler telescope, which searches for dips in light across 150,000 stars that could indicate the presence of an orbiting planet.
After discovering Kepler-78b, the team used ground-based telescopes to discover the planets characteristics.
The researchers used the radial velocity method, which measures the planet's tug of gravity on its star, to determine Kepler-78b's mass.
A number of Earth-sized planets have been discovered before, but Kepler-78b is the first of these planets to have both its mass and size measured. This allowed the team to gauge what the planet was made out of.
Kepler-78b is "1.2 times the size of Earth and 1.7 times more massive," which gives it a similar density to the blue planet. This suggests the newly discovered planet is made from iron and rock. Its host star is a slightly less massive than our own Sun and is 400 light-years away, located in the Cygnus constellation.
