Planets usually orbit stars, taking advantage of their light and energy that can eventually lead to the formation of life. But there are also dark planets out there that do not revolve around any star – they’re called rogue planets, and they are completely unilluminated. Therefore, it’s very hard to spot such cosmic objects in space, but science always seems to have an ace up its sleeve.
One way that scientists believe rogue planets could form is that they’re getting hit by other planets while all of them were part of a solar system. Just like our Earth was hit by another body to form the Moon millions of years ago, other objects may have become rogue planets by following a similar pattern.
Praise gravitational lensing!
Scientists found a new rogue planet that’s similar to Earth in size: it’s called OGLE-2016-BLG-1928, and it was detected through the micro-lensing technique and by the KMTN (Korean Microlensing Telescope Network) collaboration. The planet floats freely and lonely through the Milky Way, and it’s also considered to be a low mass planet.
Since rogue planets cannot be observed by telescopes as they lack any light upon their surfaces, scientists are counting on the gravitational lensing method (aka micro-lensing) predicted by the great Albert Einstein. Since any massive object bends space and causes light to deflect slightly, the light itself is amplified like in a magnifying glass.
As weird as they are, rogue planets are predicted to be very common throughout the Milky Way. Our galaxy could be hosting billions to trillions of planets that do not revolve around any star, and the upcoming Nancy Grace Roman Space Telescope will likely shed some light on the mystery and reveal just how many of these lonely planets truly are in our galaxy.
Until that moment, let’s be thankful that our Earth doesn’t show any signs of becoming a rogue planet.