One Side of This White Dwarf is Covered in Hydrogen While the Other Side is Helium.

Here's a new one. Astronomers have found a white dwarf star - the dead remnant from a main sequence star like the Sun - with one hemisphere composed of hydrogen while the other is covered in helium. The star was discovered with the Zwicky Transient Facility, revealing that it rotates every 15 minutes. Spectroscopic data unveiled its two-sided nature. What?! Also. How?! Some white dwarfs transition from hydrogen- to helium-dominated surfaces, and astronomers might have caught it in the act. The p...