Spectral classification of (relatively) bright stars

American Association of Variable Star Observers (AAVSO)
Sat, 06/01/2024 - 07:30

Hi all. I'm looking for spectral classification of WISEA J082158.50+402348.0 , there seems to be no data in VizieR, in NED and SDSS.

Any suggestion ?

Thanks a lot


American Association of Variable Star Observers (AAVSO)
Specral classification for WISE star

     Actually there is a spectral type for the star in VizieR, which is BD+40 2033 --- the much-preferred designation.  It appears in the AGK3 catalogue (VizieR file i/61b), and derives from work by Alexander Vyssotsky in the 1950s.  His type is M2.  This type is copied into the SIMBAD header page for the star, though there is no citation.  The proper motion is very small, so it is almost certainly a giant.  There is also an actual low-resolution spectrum in the GAIA survey, under VizieR file i/355/spectra.  I have a fair amount of experience classifying such spectra, and would call it M3III, consistent with the Vyssotsky type within the likely errors on both sides.

     NED deals with galaxies, so is not a relevant information source.  A star this bright is very much overexposed in the original SDSS surveys (saturation limit there about mag 14 or 15), so whatever data from that source will be unreliable.