CWISEP J1047+5457

CWISEP J1047+5457

Hubble WFC3 image of CWISEP J1047+5457 (blue cross-hair)
Observation data Epoch J2000      Equinox J2000
Constellation	Ursa Major
Right ascension	10^h 47^m 57.50^s
Declination	+54° 57′ 42.17″
Characteristics
Evolutionary stage	brown dwarf
Spectral type	Y1[1]
Astrometry
Proper motion (μ)	RA: –447.9 ±41.7 mas/yr[2] Dec.: –65.5 ±35.2 mas/yr[2]
Parallax (π)	68.1 ± 4.9 mas[1]
Distance	48 ± 3 ly (15 ± 1 pc)
Details
Mass	20.6 or 15.9[3] MJ or 1–3[4] MJup
Radius	0.94 ± 0.07 or 0.98 ± 0.07[3] RJup
Luminosity (bolometric)	10^-6.582 ± 0.063[1] L☉
Temperature	415+20 −22[1] K
Age	40–200[4] Myr
Age	6.73 or 5.01[3] Gyr
Other designations
CWISEP J104756.81+545741.6
Database references
SIMBAD	data

CWISEP J1047+5457 (CWISEP J104756.81+545741.6, CWISEP J1047+54) is a Y-dwarf discovered in 2020.[5]

CWISEP J1047+5457 was discovered in 2020 from a preliminary CatWISE catalog, initially determined to have a spectral type of Y0.[5] Follow-up observations with JWST spectroscopy (NIRSpec and MIRI) showed that it had a spectral type of Y1. The observations showed that it had unusually strong carbon monoxide and carbon dioxide absorption. This causes the Spitzer ch1-ch2 color to be extremely blue (2.47 ±0.19 mag) for its spectral type and explains the misidentification as a Y0 in the discovery paper. The strong absorption might be explained with extreme disequilibrium chemistry, low surface gravity, or a low carbon to oxygen ratio. Other molecules, such as water vapor, methane and ammonia are also detected in the spectra. Phosphine is not detected.[1]

Another study suspects this object to be young and low mass. The researchers find that increased amount of CO and CO₂ can be explained with a low gravity. A low gravity is commonly associated with a young age for brown dwarfs. The researchers estimate a mass of less than 3 M_J for an age of 200 Myr. The researchers also find a 52% likelyhood that it belongs to the 40 Myr old Argus association, which would lower the mass to around 1 M_J.[4] This would make it one of the lowest-mass free-floating planetary-mass objects.

See also

• List of Y-dwarfs
• CWISE J1055+5443 is another Y-dwarf with blue ch1-ch2 color, here this is explained with a young age
• List of star systems within 45–50 light-years

References

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". arXiv:2407.08518 [astro-ph.SR].
2. Kirkpatrick, J. Davy; Gelino, Christopher R.; Faherty, Jacqueline K.; Meisner, Aaron M.; Caselden, Dan; Schneider, Adam C.; Marocco, Federico; Cayago, Alfred J.; Smart, R. L.; Eisenhardt, Peter R.; Kuchner, Marc J.; Wright, Edward L.; Cushing, Michael C.; Allers, Katelyn N.; Bardalez Gagliuffi, Daniella C. (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. arXiv:2011.11616. Bibcode:2021ApJS..253....7K. doi:10.3847/1538-4365/abd107. ISSN 0067-0049.
3. Zhijun, Tu; Shu, Wang; Liu, Jifeng (28 September 2024). "Physical Parameters and Properties of 20 Cold Brown Dwarfs in JWST". arXiv:2409.19191 [astro-ph].
4. Albert, Loïc; Leggett, Sandy K.; Calissendorff, Per; Vandal, Thomas; Kirkpatrick, J. Davy; Gagliuffi, Daniella C. Bardalez; Furio, Matthew De; Meyer, Michael; Beichman, Charles A. (2025-01-23). "JWST 1.5 μm and 4.8 μm Photometry of Y Dwarfs". arXiv:2501.14100 [astro-ph].
5. Meisner, Aaron M.; Caselden, Dan; Kirkpatrick, J. Davy; Marocco, Federico; Gelino, Christopher R.; Cushing, Michael C.; Eisenhardt, Peter R. M.; Wright, Edward L.; Faherty, Jacqueline K.; Koontz, Renata; Marchese, Elijah J.; Khalil, Mohammed; Fowler, John W.; Schlafly, Edward F. (2020-02-01). "Expanding the Y Dwarf Census with Spitzer Follow-up of the Coldest CatWISE Solar Neighborhood Discoveries". The Astrophysical Journal. 889 (2): 74. arXiv:1911.12372. Bibcode:2020ApJ...889...74M. doi:10.3847/1538-4357/ab6215. ISSN 0004-637X.