Astronomy:WISE 0825+2805

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Short description: Brown dwarf in the constellation Cancer
WISE 0825+2805
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WISE 0825+2805
Credit: JWST/MIRI; Faherty et al.
Observation data
Equinox J2000.0]] (ICRS)
Constellation Cancer[1]
Right ascension  08h 25m 07.35720s[2]
Declination +28° 05′ 48.5592″[2]
Characteristics
Evolutionary stage Sub-brown dwarf
Spectral type Y0.5[3]
Apparent magnitude (J) 22.53±0.10
Apparent magnitude (H) 23.09±0.18
Astrometry
Radial velocity (Rv)−18.7±3.4[4] km/s
Proper motion (μ) RA: −66.7±0.9[2] mas/yr
Dec.: −235.8±0.9[2] mas/yr
Parallax (π)152.6 ± 2[2] mas
Distance21.4 ± 0.3 ly
(6.55 ± 0.09 pc)
Details[4]
Mass3.7±0.2 MJup
Radius1.144±0.002 RJup
Surface gravity (log g)3.85±0.02 cgs
Temperature359±3 K
Age414±23 Myr
Other designations
WISEA J082507.37+280548.2, WISE J082507.35+280548.5
Database references
SIMBADdata

WISE 0825+2805 (WISE J082507.35+280548.5) is a planetary mass brown dwarf or rogue planet with a spectral type of Y0.5.[3] It is about 21.4 light-years away from Earth in the Cancer constellation.[5] It is a potential member (93% chance) of the Corona of Ursa Major (CUMA) moving group, a collection of young stars that are 414±23 million years old.[4] If WISE 0825+2805 has the same age as the CUMA moving group, then its spectral energy distribution suggests it has a mass of 3.7±0.2 Jupiter masses, a radius of 1.144±0.002 Jupiter radii, and an effective temperature of 359 ± 3 K (86 ± 3 °C; 187 ± 5 °F).[4]

Discovery

WISE 0825+2805 was discovered in 2015 by Schneider et al. with the Wide-field Infrared Survey Explorer and the Hubble Space Telescope, using WFC3 near-infrared grism spectroscopy. The team also announced the discovery of three T-dwarfs as well as two additional Y-dwarfs (WISE J1206+8401 and WISE J2354+0240) in the same paper.[3]

Physical properties

WISE 0825+2805 has been observed with the James Webb Space Telescope's NIRCam and MIRI instruments. A best-fit model of WISE 0825+2805's spectral energy distribution (SED) indicates that its atmosphere is phosphine-free and diabatic. A good-fitting SED model requires an effective temperature of 350 Kelvin and a surface gravity of log g = 4.0. Alternatively, a lower surface gravity could improve the SED fit. The model parameters correspond to a mass of 5 ||J}}}}}} and an age of 800 Myrs.[6] On the other hand, if WISE 0825+2805 is the same age as the Corona of Ursa Major moving group (414±23 Myr), then the best-fit SED indicates a mass of 3.7±0.2 MJ, a radius of 1.144±0.002 RJ, and an effective temperature of 359 ± 3 K (86 ± 3 °C; 187 ± 5 °F).[4]

See also

References

  1. 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. Bibcode1987PASP...99..695R  Constellation record for this object at VizieR.
  2. 2.0 2.1 2.2 2.3 Kirkpatrick, J. Davy et al. (2021). "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. Bibcode2021ApJS..253....7K. 
  3. 3.0 3.1 3.2 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. Bibcode2015ApJ...804...92S. 
  4. 4.0 4.1 4.2 4.3 4.4 Kiman, Rocio; Beichman, Charles A.; Diaz, Azul Ruiz; Faherty, Jacqueline K.; Lacy, Brianna; Suarez, Genaro; Marocco, Federico; Kirkpatrick, J. Davy et al. (January 2026). "The Diversity of Cold Worlds: Age and Characterization of the Exoplanet COCONUTS-2b". The Astronomical Journal 171 (2): 60. doi:10.3847/1538-3881/ae230f. 
  5. Kirkpatrick, J. Davy et al. (December 2023). "The Initial Mass Function Based on the Full-sky 20-pc Census of ∼3,600 Stars and Brown Dwarfs" (in en). The Astrophysical Journal Supplement Series 271 (2): 55. doi:10.3847/1538-4365/ad24e2. Bibcode2024ApJS..271...55K. 
  6. Leggett, S. K.; Tremblin, Pascal (2024-01-01). "James Webb Space Telescope Spectra of Cold Brown Dwarfs are Well-reproduced by Phosphine-free, Diabatic, ATMO2020++ Models". Research Notes of the American Astronomical Society 8 (1): 13. doi:10.3847/2515-5172/ad1b61. ISSN 2515-5172. Bibcode2024RNAAS...8...13L.