OGLE-2016-BLG-1928
 Artistic representation of a rogue planet. | |
| Discovery | |
|---|---|
| Discovery date | 2020 |
| Microlensing[1] | |
| Physical characteristics | |
| Mass | 0.3 or 2 M🜨[1] |
OGLE-2016-BLG-1928 is an exoplanet located in the constellation Sagittarius, discovered via gravitational microlensing.[2][a] It is likely to be a rogue (free-floating) planet, as no host star was detected within 8 astronomical units.[1]
This likely free-floating planet has a mass of either 0.3 ME, if it is located within the galactic disk, or 2 M🜨 is located in the galactic bulge. The former scenario is the most likely.[1] Low-mass rogue planets like OGLE-2016-BLG-1928 are thought to be very common in the Milky Way, but few have been spotted as they are very hard to detect.[3] It is believed that these planets have been ejected from their origin planetary systems.[4]
Discovery
[edit]
OGLE-2016-BLG-1928 was discovered through a gravitational microlensing event observed by the Optical Gravitational Lensing Experiment (OGLE) and Korea Microlensing Telescope Network (KMT-N) surveys. This event had the shorest duration of any observed, at just 41.5 minutes. The discovery was announced in 2020 by a team of astronomers led by P. Mroz.[1] A microlensing event happens when the observer, the planet and a background star are aligned: The planet's gravitational effect magnifies, distorts and creates multiple images of the background star.[4]
Microlensing is an useful method for detecting planets that emit little or no radiation.[4]
See also
[edit]Notes
[edit]- ^ Constellation was inferred from exoplanet.eu's coordinates using this website.
References
[edit]- ^ a b c d e Mróz, Przemek; Poleski, Radosław; Gould, Andrew; Udalski, Andrzej; Sumi, Takahiro; and; Szymański, Michał K.; Soszyński, Igor; Pietrukowicz, Paweł; Kozłowski, Szymon; Skowron, Jan; Ulaczyk, Krzysztof; Collaboration), (OGLE; Albrow, Michael D.; Chung, Sun-Ju (October 2020). "A Terrestrial-mass Rogue Planet Candidate Detected in the Shortest-timescale Microlensing Event". The Astrophysical Journal Letters. 903 (1): L11. arXiv:2009.12377. Bibcode:2020ApJ...903L..11M. doi:10.3847/2041-8213/abbfad. ISSN 2041-8205.
- ^ Martin, Pierre-Yves (2023). "Planet OGLE-2016-BLG-1928". exoplanet.eu. Retrieved 2024-01-08.
- ^ Wall, Mike (November 4, 2020). "Tiny rogue planet is the smallest free-floating exoplanet candidate yet". space.com. Retrieved January 8, 2024.
- ^ a b c "First 'Earth Without A Sun' Discovered: Thousands More To Be Revealed Soon". Big Think. 2020-11-09. Retrieved 2024-01-11.