Tag

Helium Burning

All articles tagged with #helium burning

astronomy2 years ago

Unexplained Survival: Astronomers Discover a Mysterious 'Zombie Planet'

Astronomers have discovered a planet, named Halla, orbiting a red giant star called Baekdu, which is currently fusing helium in its core. This is puzzling because the star should have grown so large in the past that it would have engulfed the planet. Possible explanations include the star being part of a binary system, preventing its expansion, or the planet being a relatively newborn one formed from a collision between two stars. This discovery challenges our understanding of where exoplanets can exist.

astronomy2 years ago

Supersoft X-ray source found in helium-burning white dwarf binary

Astronomers have discovered a binary star system in which a white dwarf is accreting helium from its companion, leading to stable helium burning on its surface. The system was identified due to bright super-soft X-rays originating from the nuclear fusion of the overflowed gas near the surface of the white dwarf. The measured luminosity suggests that the mass of the white dwarf is growing more slowly than previously thought possible, which may help to understand the number of supernovae caused by exploding white dwarfs. The discovery could help to further constrain the conditions for Type Ia supernova progenitors.