GRW +70 8247 [SEP] constellation
GRW +70 8247
GRW +70 8247 is a white dwarf located about 43 light-years from Earth in the constellation Draco. With a magnitude of about 13 it is visible only through a large telescope.
Properties.
Although photographed in the 19th century as part of the Carte du Ciel project, it was not determined to be a white dwarf until observed in 1934 by G. P. Kuiper. This makes it the fifth or sixth white dwarf discovered. At first, its spectrum was thought to be almost featureless, but
of planetary nebulae and winds and the fields on in situ dynamos. Orbit and rotation periods are synchronized in strongly magnetized WDs. Those with no detectable field never are synchronized.
With temperatures in the range 11,000 to 15,000 K, all the WDs with the most extreme fields are far too cool to be detectable EUV/X-ray sources, e.g., Grw +70°8247, LB 11146, SBS 1349+5434, PG 1031+234 and GD 229.
Most highly magnetic WDs appear to be isolated objects,