White dwarf

The ingredients in stars are usually pretty evenly mixed throughout, but now astronomers have discovered a bizarre star with two distinct faces, each made of a different element, which defies explanation.

What was once thought to be just one star is actually two. What's more, the two stars are so close that they've broken a record for being the tightest ultracool binary system ever observed, revolving around each other in less than an Earth day.

Planets have been born, lived and died long before Earth even existed. Now astronomers have detected the ruins of ancient planets around two unusual white dwarf stars, including an Earth-like world that existed almost 10 billion years ago.

A new signal deepens the mystery of fast radio bursts with a few oddities – it hails from an unexpected region of space, and its pulses are about a million times shorter than most, which could indicate many others like it are going undetected.

Astronomers have discovered a new type of star, and exactly how these weird white dwarfs came to be remains a mystery. They're covered in a layer of “ash” that’s usually produced by burning helium, indicating they may have formed as other stars collided.

Supernovae usually appear suddenly in the sky, but now astronomers have spotted one in advance. The telltale sign is a star with a “teardrop” shape, as it gets stretched out by the gravitational pull of a companion.

Astronomers have discovered the smallest but most massive white dwarf ever found. The tiny star is only the size of our Moon, but packs in more mass than the Sun, meaning it’s approaching the theoretical limit of what’s possible without exploding.

Astronomers have used computer modeling to reveal the chaotic fate of a distant solar system in which the planets orbit in near perfect synchronization, and in the process shed light on how ancient white dwarfs become polluted with debris.

Astronomers have identified the remains of a rare type of supernova in our home galaxy for the first time. These events, known as Type Iax supernovae, occur when white dwarfs explode and may leave behind a “zombie star.”

NASA has discovered a strange star system where a gas giant planet is tightly orbiting a tiny white dwarf. This the first sighting of such an arrangement, raising questions about how the planet survived the star’s expansive death in the first place.

The universe will most likely end by slowly fading to black over trillions of years. Now a theoretical physicist has calculated the last interesting event that will ever happen: the explosions of stars called black dwarfs, which don’t even exist yet.

A supernova may seem like a pretty final fate, but now astronomers have discovered a star that apparently survived this explosive process. It wasn’t without consequence, however – the star was kicked out of a binary orbit and flung across the galaxy.