Although photographed in the 19th century as part of the Carte du Ciel project, the star was not determined to be a white dwarf until G. P. Kuiper observed it in 1934.[6] This makes it the fifth or sixth white dwarf discovered.[a] At first, its spectrum was thought to be almost featureless,[6] but later observation showed it to have unusual broad, shallow absorption bands.[10][11] In 1970, when light that it emitted was observed to be circularly polarized, it became the first white dwarf known to have a magnetic field.[12][13] In the 1980s, it was realized that the unusual absorption bands could be explained as hydrogen absorption lines shifted by the Zeeman effect.[5][14][15]
Notes[]
^The star EGGR 37 was suspected to be a white dwarf by April 1934,[7] but this was not confirmed until 1938.[8][9]
^Wesemael, F.; Greenstein, J. L.; Liebert, James; Lamontagne, R.; Fontaine, G.; Bergeron, P.; Glaspey, J. W. (1993). "An atlas of optical spectra of white-dwarf stars". Publications of the Astronomical Society of the Pacific. 105: 761. Bibcode:1993PASP..105..761W. doi:10.1086/133228.
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