  DENIS 0255−4700 Location of DENIS 0255−4700 in the constellation Eridanus | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Eridanus |
| Right ascension | 02h 55m 03.693s[1] |
| Declination | −47° 00′ 51.36″[1] |
| Characteristics | |
| Spectral type | L8/L9[2] |
| Apparent magnitude (V) | ~22.9[3] |
| Apparent magnitude (R) | ~20.1[3] |
| Apparent magnitude (I) | ~17.2[3] |
| Apparent magnitude (J) | ~13.2[3] |
| Astrometry | |
| Proper motion (μ) | RA: 1,012.445 mas/yr[1] Dec.: −554.031 mas/yr[1] |
| Parallax (π) | 205.4251 ± 0.1857 mas[1] |
| Distance | 15.88 ± 0.01 ly (4.868 ± 0.004 pc) |
| Absolute magnitude (MV) | 24.44 |
| Details | |
| Mass | 0.0578[4] M☉ |
| Radius | 0.0776[4] R☉ |
| Luminosity | 0.0000154[4] L☉ |
| Temperature | ~1300[2][4] K |
| Rotation | 1.7 hours[5] |
| Rotational velocity (v sin i) | 40.8±8.0[5] km/s |
| Age | 0.3–10[2] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
DENIS 0255−4700 is an extremely faint brown dwarf 15.9 light-years (4.9 parsecs) from the Solar System in the southern constellation of Eridanus.[3][7] It is the closest isolated L-type brown dwarf (no undiscovered L-dwarfs are expected to be closer), and only after the binary Luhman 16. It is also the faintest brown dwarf (with the absolute magnitude of MV=24.44) having measured visible magnitude.[8] A number of nearer T and Y-type dwarfs are known, specifically WISE 0855−0714, Epsilon Indi B and C, SCR 1845-6357 B, and UGPS 0722−05.
History of observations
[edit]DENIS 0255−4700 was identified for the first time as a probable nearby object in 1999.[7] Its proximity to the Solar System was established by the RECONS group in 2006 when its trigonometric parallax was measured.[8] DENIS 0255-4700 has a relatively small tangential velocity of 27.0 ± 0.5 km/s.[2]
Properties
[edit]The photospheric temperature of DENIS 0255−4700 is estimated at 1300 K.[2] Its atmosphere in addition to hydrogen and helium contains water vapor, methane and possibly ammonia.[9] The mass of DENIS 0255−4700 lies in the range from 25 to 65 Jupiter masses corresponding to the age range from 0.3 to 10 billion years.[2] The brown dwarf is rotating rapidly with the period of 1.7 hours, and its rotational axis is inclined 40 degrees from the line-of-sight.[5]
See also
[edit]References
[edit]- ^ a b c d Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b c d e f Stephens, Denise C.; Leggett, Sandy K.; Cushing, Michael C.; Marley, Mark S.; Saumon, Didier; Geballe, Thomas R.; Golimowski, David A.; Fan, Xiaohui; Noll, Keith S. (2009). "The 0.8–14.5 μm Spectra of Mid-L to Mid-T Dwarfs: Diagnostics of Effective Temperature, Grain Sedimentation, Gas Transport, and Surface Gravity". The Astrophysical Journal. 702 (1): 154–170. arXiv:0906.2991. Bibcode:2009ApJ...702..154S. doi:10.1088/0004-637X/702/1/154. S2CID 118650774.
- ^ a b c d e "2MUCD 10158 – Brown Dwarf (M<0.08 M☉)". Centre de données astronomiques de Strasbourg. Retrieved 2009-12-14.
- ^ a b c d Cifuentes, C.; Caballero, J. A.; Cortés-Contreras, M.; Montes, D.; Abellán, F. J.; Dorda, R.; Holgado, G.; Zapatero Osorio, M. R.; Morales, J. C.; Amado, P. J.; Passegger, V. M.; Quirrenbach, A.; Reiners, A.; Ribas, I.; Sanz-Forcada, J. (2020-10-01). "CARMENES input catalogue of M dwarfs. V. Luminosities, colours, and spectral energy distributions". Astronomy and Astrophysics. 642: A115. arXiv:2007.15077. Bibcode:2020A&A...642A.115C. doi:10.1051/0004-6361/202038295. ISSN 0004-6361.
- ^ a b c Zapatero Osorio, M. R.; Martin, E. L.; Bouy, H.; Tata, R.; Deshpande, R.; Wainscoat, R. J. (2006), "Spectroscopic Rotational Velocities of Brown Dwarfs", The Astrophysical Journal, 647 (2): 1405–1412, arXiv:astro-ph/0603194, Bibcode:2006ApJ...647.1405Z, doi:10.1086/505484, S2CID 14358043
- ^ Golovin, Alex; Reffert, Sabine; Just, Andreas; Jordan, Stefan; Vani, Akash; Jahreiß, Hartmut (November 2022). "The Fifth Catalogue of Nearby Stars (CNS5)". Astronomy & Astrophysics. 670: A19. arXiv:2211.01449. Bibcode:2023A&A...670A..19G. doi:10.1051/0004-6361/202244250. S2CID 253264922. Catalogue can be accessed here.
- ^ a b "Discovery of the Nearest L Dwarf: the Intrinsically Faintest Object at Visual Wavelengths Known Beyond our Solar System". RECONS. Retrieved 2007-06-17.
- ^ a b Costa, E.; Méndez, R. A.; Jao, W. -C.; Henry, T. J.; Subasavage, J. P.; Ianna, P. A. (2006). "The Solar Neighborhood. XVI. Parallaxes from CTIOPI: Final Results from the 1.5 m Telescope Program". The Astronomical Journal. 132 (3): 1234. Bibcode:2006AJ....132.1234C. CiteSeerX 10.1.1.622.2310. doi:10.1086/505706. S2CID 18952940.
- ^ Cushing, Michael C. (2006). "Spitzer Space Telescope Observations of M, L, and T Dwarfs". ASP Conference Series. 357: 66–67. Bibcode:2006ASPC..357...66C.
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction