Pdf | White Dwarf 458
Looking into it, WD 458 could be a white dwarf star's designation. The prefix WD stands for White Dwarf in some catalogs. For example, there's WD 1337-083, which is a white dwarf. So WD 458 is a possibility. If that's the case, maybe there's a research paper titled "The Atmosphere of White Dwarf WD 458" or something similar, and the user found a PDF about it.
