Astronomy:WISE J2354+0240
250px WISE J2354+0240 with NIRCam | |
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Pisces[1] |
| Right ascension | 23h 54m 02.42s[2] |
| Declination | +02° 40′ 18.5″[2] |
| Characteristics | |
| Evolutionary stage | brown dwarf or planetary-mass object[2] |
| Spectral type | Y1[2] |
| Astrometry | |
| Proper motion (μ) | RA: +503.5±2.3[2] mas/yr Dec.: −399.5±2.2[2] mas/yr |
| Parallax (π) | 130.6 ± 3.3[2] mas |
| Distance | 25.0 ± 0.6 ly (7.7 ± 0.2 pc) |
| Details | |
| Mass | 14+1 −2[3] MJup |
| Radius | 0.88+0.02 −0.01[3] RJup |
| Luminosity (bolometric) | 10−6.800±0.023[4] L☉ |
| Surface gravity (log g) | 4.65±0.05[3] cgs |
| Temperature | 371±4[3] K |
| Metallicity | Template:M/H[3] |
| Age | 6[3] Gyr |
| Other designations | |
WISEA J235402.79+024014.1, CNS5 5897, WISE J235402.77+024015.0 | |
| Database references | |
| SIMBAD | data |
WISE J2354+0240 (WISE J235402.77+024015.0, WISE 2354+0240) is a brown dwarf or free-floating planetary-mass object. It is a Y-dwarf, meaning it is one of the coldest directly imaged astronomical objects.[2]
It was discovered in 2015, using the Wide-field Infrared Survey Explorer and spectroscopy from the Hubble Space Telescope. The authors find that the J-band peak in the spectrum is narrower than the Y0 standard and therefore assigned a spectral type of Y1, with an estimated temperature of 300−400 Kelvin. The age was estimated to be at least 1.5 billion years.[2] Parallax measurement places this object at 7.7 parsec from the Solar System.[5]
Near-infrared photometry was later obtained with Hubble and a temperature of 335±11 K and a mass of 11±3 |♃|J}}}}}} was estimated.[6] WISE 2354+0240 was observed with the James Webb Space Telescope and the temperature was estimated to be 362+10
−12 K. The object is not described in detail in this work. The authors however mention that they see a number of absorption features in their sample, including water vapor, methane, ammonia, carbon monoxide and carbon dioxide. They note that none of their objects show absorption due to phosphine, which is predicted to occur in these objects.[4]
An analysis of nearby stellar associations and open clusters found that WISE 2354+0240 has a 85.2% probability of belonging to the group HSC517, which does result in a mass estimate of 2.5+2.0
−1.3 |♃|J}}}}}}. This is one of the lowest mass estimates in their list.[7][lower-alpha 1]
See also
- List of Y-dwarfs
- WISE 0825+2805 another Y-dwarf discovered by Schneider et al. 2015
Notes
- ↑ Currently only a pre-print. The full designation of HSC517 will be available once the paper is published.
References
- ↑ Roman, Nancy G. (1987). "Identification of a constellation from a position". Publications of the Astronomical Society of the Pacific 99 (617): 695. doi:10.1086/132034. Bibcode: 1987PASP...99..695R Constellation record for this object at VizieR.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 Schneider, Adam C.; Cushing, Michael C.; Kirkpatrick, J. Davy; Gelino, Christopher R.; Mace, Gregory N.; Wright, Edward L.; Eisenhardt, Peter R.; Skrutskie, M. F. et al. (2015-05-01). "Hubble Space Telescope Spectroscopy of Brown Dwarfs Discovered with the Wide-field Infrared Survey Explorer". The Astrophysical Journal 804 (2): 92. doi:10.1088/0004-637X/804/2/92. ISSN 0004-637X. Bibcode: 2015ApJ...804...92S.
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 Kothari, Harshil; Cushing, Michael C.; Beiler, Samuel A.; Visscher, Channon; Marley, Mark S.; Burningham, Ben; Schneider, Adam C.; Kirkpatrick, J. Davy (2026-04-06). "A Comprehensive Atmospheric Retrieval Analysis of 22 James Webb Space Telescope Spectral Energy Distributions of Cool Brown Dwarfs". arXiv:2604.05104 [astro-ph.SR].
- ↑ 4.0 4.1 Beiler, Samuel A.; Cushing, Michael C.; Kirkpatrick, J. Davy; Schneider, Adam C.; Mukherjee, Sagnick; Marley, Mark S.; Marocco, Federico; Smart, Richard L. (11 Jul 2024). "Precise Bolometric Luminosities and Effective Temperatures of 23 late-T and Y dwarfs Obtained with JWST". The Astrophysical Journal 973 (2): 107. doi:10.3847/1538-4357/ad6301. Bibcode: 2024ApJ...973..107B.
- ↑ Kirkpatrick, J. Davy; Gelino, Christopher R.; Faherty, Jacqueline K.; Meisner, Aaron M.; Caselden, Dan; Schneider, Adam C.; Marocco, Federico; Cayago, Alfred J. et al. (2021-03-01). "The Field Substellar Mass Function Based on the Full-sky 20 pc Census of 525 L, T, and Y Dwarfs". The Astrophysical Journal Supplement Series 253 (1): 7. doi:10.3847/1538-4365/abd107. ISSN 0067-0049. Bibcode: 2021ApJS..253....7K.
- ↑ Fontanive, Clémence; Bedin, Luigi R.; De Furio, Matthew; Biller, Beth; Anderson, Jay; Bonavita, Mariangela; Allers, Katelyn; Pantoja, Blake (2023-12-01). "An HST survey of 33 T8 to Y1 brown dwarfs: NIR photometry and multiplicity of the coldest isolated objects". Monthly Notices of the Royal Astronomical Society 526 (2): 1783–1798. doi:10.1093/mnras/stad2870. ISSN 0035-8711. Bibcode: 2023MNRAS.526.1783F.
- ↑ Gagné, Jonathan; Moranta, Leslie; Faherty, Jacqueline K.; Curtis, Jason Lee; Bickle, Thomas P.; Couture, Dominic; Chiasson David, Amélie; Christie, Katie et al. (17 Feb 2026). "The Montreal Open Clusters and Associations (MOCA) Database: A Census of Nearby Associations, Open Clusters, and Young Substellar Objects within 500 pc of the Sun" (in en). arXiv e-prints: arXiv:2602.15695. https://ui.adsabs.harvard.edu/abs/2026arXiv260215695G/abstract.
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