UX Tauri

UX Tauri

An artist's conception of a circumstellar disk around UX Tauri A, along with several hypothetical protoplanets.
Observation data Epoch J2000.0      Equinox J2000.0
Constellation	Taurus
Right ascension	04^h 30^m 03.99626^s[1]
Declination	+18° 13′ 49.4355″[1]
Apparent magnitude (V)	+10.80[2]
Characteristics
Spectral type	K2Ve + M1Ve[3]
Astrometry
Radial velocity (Rv)	22.90[4] km/s
Proper motion (μ)	RA: 17.18[1] mas/yr Dec.: -21.91[1] mas/yr
Parallax (π)	-3.70[1] ± 5.73 mas
Distance	450 ly (138 pc)
Details[5]
UX Tauri A
Mass	1.25 M☉
Luminosity	1.3 L☉
Surface gravity (log g)	4.0 cgs
Temperature	4460 K
Age	3 Myr
UX Tauri B
Mass	0.4 M☉
Luminosity	0.5 L☉
Surface gravity (log g)	3.5 cgs
Temperature	3500 K
Age	1 Myr
Other designations
UX Tau, HD 285846, HIP 20990, WDS J04301+1814AB, CCDM J04301+1814AB, 1RXS J043004.5+181342
Database references
SIMBAD	data

A visual band light curve for UX Tauri, plotted from ASAS-SN data^[6]

UX Tauri, abbreviated as UX Tau, is a binary star system approximately 450 light-years away in the constellation of Taurus (the Bull). It is notable for the fact that, despite its recent (in stellar terms) creation, the Spitzer Space Telescope discovered that its protoplanetary disk contains a gap. The dust, which normally accumulates in an expanding ring starting right next to the star at such a young age, is either very thin or nonexistent at a range of 0.2 to 56 AU from the star. Typically, this means that the early ancestors of planets may be forming from the disk, though the star only ignited about 1 million years ago.^[7] In contrast, Earth was formed approximately 4.54 billion years ago, placing its formation about sixty million years after the Sun's ignition around 4.6 billion years ago.

See also

• HD 98800
• Vega
• V4046 Sagittarii

References

1. van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600. Vizier catalog entry
2. "UX Tau". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 5 December 2016.
3. Herbig, G. H. (1977). "Radial velocities and spectral types of T Tauri stars". Astrophysical Journal. 214: 747–758. Bibcode:1977ApJ...214..747H. doi:10.1086/155304.
4. Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID 119231169.
5. Magazzu, A. (1991). "Lithium in the pre-main sequence triple system UX Tauri". Astronomy and Astrophysics. 249 (1): 149–155. Bibcode:1991A&A...249..149M.
6. "ASAS-SN Variable Stars Database". ASAS-SN Variable Stars Database. ASAS-SN. Retrieved 6 January 2022.
7. "NASA - Youthful Star Sprouts Planets Early". Archived from the original on 2012-10-21. Retrieved 2007-11-28.

External links

• Magazzu, A.; Martin, E. L.; Rebolo, R. (September 1991). "Lithium in the pre-main sequence triple system UX Tauri". Astronomy and Astrophysics. 249 (1): 149. Bibcode:1991A&A...249..149M.
• "UX Tauri". Jumk.de. Retrieved 2008-06-16.