Researchers observed a super-Earth pass in front of a Sun-like star from a ground-based telescope for the first time.
Detecting the planet's transit could allow the researchers to gain insight into the composition of its atmosphere, Harvard-Smithsonian Center for Astrophysics reported.
Through their observations the researchers determined the planet, dubbed 55 Cancri, crosses in front of its host star and blocks the starlight from our view for about two hours. Calculations using this data suggest the planet is about twice the size of Earth.
"Our observations show that we can detect the transits of small planets around Sun-like stars using ground-based telescopes," said Ernst de Mooij of Queen's University Belfast in the United Kingdom, lead author of the study. "This is especially important because upcoming space missions such as TESS and PLATO should find many small planets around bright stars and we will want to follow up the discoveries with ground-based instruments.
The NASA TESS mission is scheduled to launch in 2017 and PLATO will takeoff in 2024 by the European Space Agency. The goal of both missions is to sear for planets orbiting bright stars.
"With this result we are also closing in on the detection of the atmospheres of small planets with ground-based telescopes," said co-author Mercedes Lopez-Morales of the Harvard-Smithsonian Center for Astrophysics (CfA). "We are slowly paving the way toward the detection of bio-signatures in Earth-like planets around nearby stars."
The fascinating planet 55 Cancri is believed to be about eight times as massive as Earth with a period of 18 hours, it is the innermost of a system of five planets. Since it is so close to its host star it is believed to reach a scorching temperature of 3,100 degrees Fahrenheit, which is hot enough to melt metal.
Before this observation only one other super-Earth transit had been observed using a ground-based telescope, but this object passed in front of a red dwarf; this new successful observation could help lead to similar accomplishments in the future.
"We expect these surveys to find so many nearby, terrestrial worlds that space telescopes simply won't be able to follow up on all of them. Future ground-based instrumentation will be key, and this study shows it can be done," Lopez-Morales said.
The findings were published in a recent edition of the Astrophysical Journal Letters.
