The latest find to come out of the European Southern Observatory (ESO) in northern Chile’s Atacama desert has caused much excitement in the international astronomy community. Floating 100 light-years from our Solar System (a short distance on a cosmological scale), scientists have spotted what they believe to be a rarely seen “rogue planet” – a planetary-mass sized celestial body that does not orbit a centralized star.
Exoplanets – planets outside of our own solar system – are notoriously difficult to see due to light and radiation interference from the stars they orbit. If this find is confirmed as a rogue planet, it could give astronomers the best view yet of any of the 849 exoplanets so far discovered.
“Looking for planets around their stars is akin to studying a firefly sitting one centimetre away from a distant, powerful car headlight,” said Philippe Delorme, an astronomer from Université Joseph Fourier in France and lead author of the new study. “This nearby free-floating object offered the opportunity to study the firefly in detail without the dazzling lights of the car messing everything up.”
There remains the possibility that the body is a small brown dwarf (a type of “failed” star), though the chance to closely analyze such a star would prove equally as interesting to astronomers since the process in which brown dwarfs are formed is still not fully understood.
“(Rogue planets and brown dwarfs) are important, as they can either help us understand more about how planets may be ejected from planetary systems, or how very light objects can arise from the star formation process,” Delorme said. “If this little object is a planet that has been ejected from its native system, it conjures up the striking image of orphaned worlds, drifting in the emptiness of space.”
Fully operational since 2000, the Very Large Telescope is currently the largest optical telescope in the world, though another telescope in Chile is set to surpass it in power. Plans are currently underway for the European Extremely Large Telescope, which is expected to enable astronomers to see further into the history of the universe than ever before.
Due to its almost non-existent humidity and clear skies, the Atacama is the planet’s premier location for astronomy. Chile is home to almost half the world’s telescope infrastructure, and this is set to increase to over two thirds by 2018.