EPIC 204278916
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Scorpius |
| Right ascension | 16h 02m 07.576s |
| Declination | −22° 57′ 46.89″ |
| Characteristics | |
| Evolutionary stage | Pre-main-sequence |
| Spectral type | M1[1] |
| Apparent magnitude (R) | 13.7[2] |
| J−H color index | 0.712 |
| J−K color index | 1.033 |
| Astrometry | |
| Proper motion (μ) | RA: −13.5±8.7[1] mas/yr Dec.: −20.0±8.8[1] mas/yr |
| Details | |
| Mass | 0.5[3] M☉ |
| Radius | 0.97[3] R☉ |
| Luminosity (bolometric) | 0.15[2] L☉ |
| Temperature | 3,673[2] K |
| Age | ≈5[3] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
EPIC 204278916 is a pre-main-sequence star, about five million years old and of spectral type M1. It is part of the Upper Scorpius sub-group of the Scorpius–Centaurus Association, and is in the constellation Scorpius. The star is approximately the size of the Sun at 0.97 R☉, but is only half its mass (0.50 M☉) and a fraction of its luminosity (0.15 L☉).[3][4]
This stellar object was first characterized by the 2nd USNO CCD Astrograph Catalog and the Two Micron All-Sky Survey, and was further studied during the Kepler space telescope's extended K2 mission Campaign 2 between 23 August and 13 November 2014.
Luminosity
In August 2016, a team of astronomers, led by Simone Scaringi of the Max Planck Institute for Extraterrestrial Physics in Germany, reported that this red dwarf star has a resolved circumstellar disc. Further, the research team observed unusual luminosity dimmings of up to 65% for 25 consecutive days (out of 79 total observation days). The variability in luminosity was highly periodic and attributed to stellar rotation. The researchers hypothesized that the irregular dimmings were caused by either a warped inner-disk edge or transiting cometary-like objects in either circular or eccentric orbits.[3]
See also
- KIC 8462852, a star showing similar light fluctuations
References
- 1 2 3 Bouy, H.; Martín, E. L. (September 2009). "Proper motions of cool and ultracool candidate members in the Upper Scorpius OB association". Astronomy and Astrophysics. 504 (3): 981–990. arXiv:0907.0149
. Bibcode:2009A&A...504..981B. doi:10.1051/0004-6361/200811088. - 1 2 3 Preibisch, Thomas; Brown, Anthony G. A.; Bridges, Terry; Guenther, Eike; Zinnecker, Hans (July 2002). "Exploring the Full Stellar Population of the Upper Scorpius OB Association". The Astronomical Journal. 124 (1): 404–416. Bibcode:2002AJ....124..404P. doi:10.1086/341174.
- 1 2 3 4 5 Scaringi, S.; Manara, C. F.; Barenfeld, S. A.; Groot, P. J.; Isella, A.; et al. (August 2016). "The peculiar dipping events in the disk-bearing young-stellar object EPIC 204278916". Monthly Notices of the Royal Astronomical Society, Advanced Access. stw2155. arXiv:1608.07291. Bibcode:2016MNRAS.tmp.1267S. doi:10.1093/mnras/stw2155.
- ↑ Nowakowski, Tomasz (30 August 2016). "Irregular dimming of a young stellar object investigated by astronomers". Phys.org. Retrieved 5 September 2016.