 Artistic representation of a rogue planet. | |
| Discovery | |
|---|---|
| Discovery date | 2020 |
| Detection method | Microlensing |
| Physical characteristics | |
| Mass | 0.3 or 2 M🜨 |
OGLE-2016-BLG-1928 is an exoplanet located in the constellation Sagittarius, discovered via gravitational microlensing. It is likely to be a rogue (free-floating) planet, as no host star was detected within 8 astronomical units.
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. 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. It is believed that these planets have been ejected from their origin planetary systems.
Discovery
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. 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.
Microlensing is an useful method for detecting planets that emit little or no radiation.
See also
Notes
- Constellation was inferred from exoplanet.eu's coordinates using this website.
References
- ^ 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.
- ^ "First 'Earth Without A Sun' Discovered: Thousands More To Be Revealed Soon". Big Think. 2020-11-09. Retrieved 2024-01-11.