World's Smallest Rogue Planet Size of Our Earth Discovered Floating in the Milky Way
Image for representation purpose only.
Astronomers have found an Earth-sized rogue planet. The findings were published in a study that has appeared on October 29 in The Astrophysical Journal Letter.
According to the USA and Polish astronomers, the planet is rogue which means that it is floating in Milky Way and is not attached to any star. It is also the world’s smallest rogue planet discovered so far, with size between Earth and Mars, as reported by Daily Mail.
Scientists believe that the number of rogue planets in Milky Way might even outnumber the stars present there.
As per the team, studying such free-floating objects can enable researchers to know about the past of the planetary systems, including that of Earth. The same team had found 10 such planets in 2011 which were approximately the size of Jupiter. They did not have any parent star within the distance of 10 astronomical units.
An astronomical phenomenon called the gravitational microlensing was used for determining the presence of the planet. The planet was discovered when it bent the light of the distant stars.
Data collected from microlensing surveys of the central part of the Milky Way — Galactic Bulge — was used to spot the planet. Chile’s Las Campanas Observatory collected the data with the help of the Warsaw Telescope.
California Institute of Technology’s astronomer Przemek Mroz, who is the author of the study, said that the chances of observing microlensing are not good because it needs the perfect alignment of three objects namely — source, lens and observer.
Commenting on their findings, paper author Radoslaw Poleski, who is an astronomer at Poland’s University of Warsaw, said that when they first spotted the event, they understood that it was caused by ‘an extremely tiny object.’
He said, “We can rule out the planet having a star within about eight astronomical units.”
It is believed that these free-floating planets might get separated from their parent planetary system after they interact gravitationally with other objects in the space.