A large planet microlensing occasion

A large planet microlensing occasion
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Giant planet microlensing event

A Hubble picture of a purple galaxy appearing as a gravitational lens for a extra distant blue galaxy, bending its gentle in an arc. Exoplanets may be detected by means of the same impact, gravitational microlensing, when a foreground star and its orbiting planet occur to move by means of a background star within the sky, creating shiny flashes. Astronomers have detected a brand new microlensing Jupiter-sized exoplanet round an M dwarf star, and are utilizing the outcome to assist determine between competing planet formation eventualities. Credit score: ESA/Hubble and NAS

Thus far, greater than 5,000 exoplanets have been detected, of which greater than 90% have been discovered utilizing transit or radial velocity methods. Of the opposite 10%, 105 have been discovered utilizing the microlensing methodology that takes benefit of the truth that the trail of a light-weight beam is deflected by the presence of a large physique. The gravitational drive of the physique acts as a lens (a “gravitational lens”) to distort the picture of an object seen behind it. When a large object occurs to move in entrance of a star, it acts as a gravitational lens, and thus its movement throughout the sky causes the background star to briefly seem to brighten. When the foreground object is a star internet hosting a planet, each our bodies can produce brightening occasions as they move in entrance of the star, and the flares seen from Earth may be modeled to find out their plenty and separation.

The microlensing methodology presents two vital benefits over extra frequent exoplanet detection methods. First, the brightness of microlensing doesn’t depend upon the brightness of the transferring physique, solely on its mass, which makes it attainable to detect faint, low-mass M-dwarf stars. The second benefit is that the microlensed planet can orbit its star at a fantastic distance, even many astronomical items. (from regular[{” attribute=””>exoplanet techniques, like transiting, require multiple detections over many orbital periods, exoplanets with large orbits take years to complete their cycle and so far the vast majority of all measured exoplanets have orbits smaller than one astronomical unit.) As a result of their large orbits, the detected giant planets around microlensing host stars are usually far enough away to reside beyond the “snow line,” the distance at which surface water would freeze.

Harvard-Smithsonian Center for Astrophysics (

Reference: “OGLE-2017-BLG-1049: Another Giant Planet Microlensing Event” Yun Hak Kim, Sun-Ju Chung, A. Udalski, Ian A. Bond, Youn Kil Jung, Andrew Gould, Michael D. Albrow, Cheongho Han, Kyu-Ha Hwang, Yoon-Hyun Ryu, In-Gu Shin, Yossi Shvartzvald, Jennifer C. Yee, Weicheng Zang, Sang-Mok Cha, Dong-Jin Kim, Hyoun-Woo Kim, Seung-Lee Kim, Chung-Uk Lee and Dong-Joo Lee, 31 December 2020, Journal of the Korean Astronomical Society.
DOI: 10.5303/JKAS.2020.53.6.161

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