Researchers have discovered a potentially habitable but frozen planet about 3,000 light-years away from earth.
The search for habitable exoplanets is still on and a new planet discovery provides further evidence that there are many celestial bodies, similar to Earth out there in space. Four international research teams, led by professor Andrew Gould of The Ohio State University discovered a new potentially habitable but frozen planet, which is located about 3,000 light-years away from earth. The planet has been named OGLE-2013-BLG-0341LBb.
What's interesting about this discovery is that the planet orbits one of the stars in the binary system at almost exactly the same distance Earth orbits the sun. It also provides the first set of evidence suggesting that terrestrial planets can form in orbits similar to Earth's, even in a binary star system where the stars are not very far apart.
Researchers noted that the star OGLE-2013-BLG-0341LBb orbits is way dimmer than the Sun, the reason why this planet is much colder than the Earth. In fact, it has temperatures that are much below Jupiter's icy moon Europa. Though this planet is practically frozen, researchers said that it could be habitable, had it orbited a sun-like star that facilitated warmer temperatures.
Researchers generally use a technique known as gravitational microlensing. So how does this detection process take place? Sometimes (though very rarely) the gravity of a star in a binary system catches the light of a more distant star and magnifies it like a lens. There are a few occasions when the light of a planet can also be detected through this magnified light. Gravitational microlensing coupled with other computer modeling makes this detection possible. The entire process can get very tricky because the light of the star and the light of the planet can interrupt each other's detection data.
"In gravitational microlensing we don't even look at the light from the star-planet system," Scott Gaudi, professor of astronomy at Ohio State, said in a press statement. "We just observe how its gravity affects light from a more distant, unrelated, star. This gives us a new tool to search for planets in binary star systems."
Signs of the new planet were first detected by OGLE (Optical Gravitational Lensing Experiment) telescope on April 11, 2013. At that time it appeared as a "dip" in the line tracing the brightness data of the star it orbits. Two weeks following the dip, the light became brighter and was observed from telescopes in Chile, New Zealand, Israel and Australia. The teams included OGLE, MOA, MicroFUN (the Microlensing Follow Up Network), and the Wise Observatory.
Specifications of OGLE-2013-BLG-0341LBb
OGLE-2013-BLG-0341LBb is twice the mass of Earth, and orbits its star from an Earth-like distance, around 90 million miles. However, its star is 400 times dimmer than the Sun. So the planet has temperatures ranging around -213 Celsius. The other star in the binary system is located at a distance from the first star similar to the distance between Saturn and the Sun.
Though three other planets have been discovered in binary systems, this is the first planet that has an Earth-like size and also follows an earth-like orbit.
"Normally, once we see that we have a binary, we stop observing. The only reason we took such intensive observations of this binary is that we already knew there was a planet," Gould said. "In the future we'll change our strategy."
The study was funded by the National Science Foundation, NASA (including a NASA Sagan Fellowship), European Research Council, Polish Ministry of Science and Higher Education, National Research Foundation of Korea, U.S.-Israel Binational Science Foundation, Japan Society for the Promotion of Science, Marsden Fund from the Royal Society of New Zealand and the Israeli Centers of Research Excellence.
The findings were published in the July 4 issue of the journal Science.
