T Coronae Borealis

T Coronae Borealis
Observation data
Epoch J2000      Equinox J2000
Constellation Corona Borealis
Right ascension 15h 59m 30.16s[1]
Declination 25° 55 12.6
Apparent magnitude (V) 2.0–10.8[1]
Characteristics
Spectral type M3III[1][2] / White Dwarf
Variable type recurrent nova (NR)[1]
Astrometry
Radial velocity (Rv)14.33[2] km/s
Parallax (π)1.61 ± 1.63[2] mas
Details
Other designations
AAVSO 1555+26, 2MASS J15593015+2555126, HD 143454, BD +26° 2765, HIP 78322, SAO 84129[2]

T Coronae Borealis (T CrB), informally nicknamed the Blaze Star,[3] is a recurring nova in the constellation Corona Borealis. It normally has a magnitude of about 10, which is near the limit of typical binoculars. It has been seen to outburst twice, reaching magnitude 2.0 on May 12, 1866 and magnitude 3.0 on February 9, 1946.[4] Though a more recent paper shows the 1866 outburst with a possible peak range of magnitude 2.5 ± 0.5.[5] Even when at peak magnitude of 2.5, this recurrent nova is dimmer than about 120 stars in the night sky.[6]

AAVSO light curve of recurrent nova T CrB from 1 Jan 2008 to 17 Nov 2010. Up is brighter and down is fainter. Day numbers are Julian day.

2016 Activity

On 20 April 2016, the Sky and Telescope newsletter reported a recent sustained brightening since February 2015 from magnitude 10.5 to about 9.2. A similar event was reported in 1938, shortly before the 1946 outburst. Closer observations are planned.

See also

References

  1. 1 2 3 4 "T CrB". AAVSO: Variable Star Plotter (VSP). Retrieved 2010-11-15.
  2. 1 2 3 4 "T Coronae Borealis". SIMBAD Astronomical Database. Retrieved 2010-11-15.
  3. A Digital Spectral Classification Atlas, R. O. Gray, 34. Unusual Stellar Spectra III: two emission-line stars
  4. Sanford, Roscoe F. (1949). "High-Dispersion Spectrograms of T Coronae Borealis.". Astrophysical Journal. 109: 81. Bibcode:1949ApJ...109...81S. doi:10.1086/145106.
  5. Schaefer, Bradley E. (2009). "Comprehensive Photometric Histories of All Known Galactic Recurrent Novae". arXiv:0912.4426Freely accessible.
  6. "Vmag<2.5". SIMBAD Astronomical Database. Retrieved 2010-06-25.

Further reading

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