Astronomers have recently found a ‘rogue planet’, which is about the same mass as Mars or Earth, drifting in the Milky Way.
‘Rogue planets’ are those planets that leave the gravitational embrace of the solar system and drift through the interstellar space forever.
A team of scientists from the OGLE (Optical Gravitational Lensing Experiment) and KMTN (Korean Microlensing Telescope Network) have now discovered a low-mass rogue planet, which has no stars near it and its distance from Earth still remains unknown.
Finding rogue planets is extremely challenging because, unlike stars, planets do not emit light of their own.
The team behind the discovery used the gravitational microlensing technique to find the planet.
Microlensing is a form of gravitational lensing where light from a background source, such as a star, is bent by the gravitational field of a foreground planet or any other source of gravity.
This creates distorted or multiple images, which show both intensity of light and position of the background source of light inaccurately.
While discovering this planet, the planet itself acted as the lens, distorting light from behind it.
However, a low-mass planet like this doesn’t bend light too much and does so only for a short period of time.
According to the astronomers, this planet’s micro-lensing event lasted only 41.5 minutes.
The researchers describe the event as the “most extreme short-timescale microlens discovered to date”.