Astronomers made the first ever observation from a ground-based telescope of a super-Earth passing in front of a nearby Sun-like star, a development that could spur them in their search for signs of life on alien planets from afar.
“Our observations show that we can detect the transits of small planets around Sun-like stars using ground-based telescopes,” said lead author Ernst de Mooij of Queen’s University Belfast in Northern Ireland.
The international research team used the Nordic Optical Telescope on the island of La Palma, Spain, to make the detection.
The host star “55 Cancri” is located just 40 light years away from us and is visible to the naked eye and the transit of the exoplanet named “55 Cancri e” is the shallowest detected from a ground-based observatory.
During its transit, the exoplanet crosses “55 Cancri” and blocks a tiny fraction of the starlight.
This shows that the planet is about twice the size of Earth or 16,000 miles in diameter.
This discovery is important because upcoming space missions such as TESS and PLATO should find many small planets around bright stars.
TESS is a NASA mission scheduled for launch in 2017 while PLATO is to be launched in 2024 by the European Space Agency.
Both will search for transiting terrestrial planets around nearby bright stars.
“We are slowly paving the way toward the detection of bio-signatures in Earth-like planets around nearby stars,” added co-author Mercedes Lopez-Morales of the Harvard-Smithsonian Center for Astrophysics.
The findings appeared in the Astrophysical Journal Letters.