Rogue Planet

4 Oct 2020

At https://universetoday.com/148097/a-rogue-earth-mass-planet-has-been-disc... ... a rogue earth mass planet has been discovered freely floating in the Milky Way, without a star in attendance. Big news. The story is also at https://phys.org/news/2020-10-rogue-earth-mass-planet-freely-milky.html ... a study which comes with 20 co-authors cited as contributors. You can read it at https://arxiv.org/abs/2009.12377 ... lead author is Przemek Mroz of Caltech. Gravitational lensing is used to find tiny objects in the darkness of space. It requires a distant light source, usually a star, and a closer object, with enough mass to act as a lens, and to bend the light from source. In this instance the low mass planet itself acted as the lens, bending the light from the light source, a distant star it is thought. The researcher added, they could not exclude the possibility of a distant stellar companion. There were no stars within a reasonable distance, said to be 8AUs. However, planets do orbit stars at greater distances than 8AUs - which is perhaps why the paper is currently at arXiv.