Popular Mechanics: There are only about 32 000 known white dwarf stars, and now one of them has been revealed to be unique among all known stars. Discovered by Kepler de Souza Oliveira of the Federal University of Rio Grande do Sul in Brazil and his colleagues, the star, which they dubbed Dox, has an outer atmosphere that is 99.9% pure oxygen. In comparison, Earth’s atmosphere is only 21% oxygen. Normal white dwarfs have atmospheres made primarily of lighter elements, the remnants of the stars’ original material. The researchers say the dwarf star may have been part of a binary system with a Sun-like star. Dox could have siphoned off material from the neighboring star and then exploded as a supernova, expelling the lightest elements and destroying its partner. The mystery is why only oxygen would have been left behind.
Despite the tumultuous history of the near-Earth object’s parent body, water may have been preserved in the asteroid for about a billion years.
October 08, 2025 08:50 PM
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Physics Today - The Week in Physics
The Week in Physics" is likely a reference to the regular updates or summaries of new physics research, such as those found in publications like Physics Today from AIP Publishing or on news aggregators like Phys.org.