NASA | JPL-Caltech | Spitzer | 2017 Apr 26
[img3="This artist's concept shows OGLE-2016-BLG-1195Lb, a planet discovered through a technique called microlensing. Credit: NASA/JPL-Caltech"]https://www.jpl.nasa.gov/spaceimages/im ... _hires.jpg[/img3][hr][/hr]Scientists have discovered a new planet with the mass of Earth, orbiting its star at the same distance that we orbit our sun. The planet is likely far too cold to be habitable for life as we know it, however, because its star is so faint. But the discovery adds to scientists' understanding of the types of planetary systems that exist beyond our own.
"This 'iceball' planet is the lowest-mass planet ever found through microlensing," said Yossi Shvartzvald ...
Microlensing is a technique that facilitates the discovery of distant objects by using background stars as flashlights. When a star crosses precisely in front of a bright star in the background, the gravity of the foreground star focuses the light of the background star, making it appear brighter. A planet orbiting the foreground object may cause an additional blip in the star's brightness. In this case, the blip only lasted a few hours. This technique has found the most distant known exoplanets from Earth, and can detect low-mass planets that are substantially farther from their stars than Earth is from our sun.
The newly discovered planet, called OGLE-2016-BLG-1195Lb, aids scientists in their quest to figure out the distribution of planets in our galaxy. An open question is whether there is a difference in the frequency of planets in the Milky Way's central bulge compared to its disk, the pancake-like region surrounding the bulge. OGLE-2016-BLG-1195Lb is located in the disk, as are two planets previously detected through microlensing by NASA's Spitzer Space Telescope. ...
An Earth-mass Planet in a 1 au Orbit around an Ultracool Dwarf - Y. Shvartzvald et al
- Astrophysical Journal Letters 840(1):L3 (2017 May 01) DOI: 10.3847/2041-8213/aa6d09
arXiv.org > astro-ph > arXiv:1703.08548 > 24 Mar 2017 (v1), 25 Apr 2017 (v2)
- arXiv.org > astro-ph > arXiv:1703.08639 > 25 Mar 2017