Most Universe Today readers are familiar with nebulae. They’re gaseous structures lit up with radiation from nearby stars, and they’re some of nature’s most beautiful forms.
With the help of amateur astronomers who laid the groundwork, an international team of astronomers have discovered a new type of nebulae around binary stars that they’re calling galactic emission nebulae.
Continue reading “Astronomers Discover a Totally New Kind of Nebula”
White dwarfs are supposed to be dead remnants of stars, doomed to simply fade away into the background. But new observations show that some are able to maintain some semblance of life by wrapping themselves in a layer of fusing hydrogen.
Continue reading “White Dwarfs can Continue Burning Hydrogen, Even After They’re Dead”
Sometimes loud explosions are easier to deal with when you know they’re coming. They are also easier to watch out for. So when astronomers from the University of Warwick found a rare tear-drop shaped star, known as HD265435, they knew they were looking at a potential new supernova waiting to happen. The only caveat – it might not actually happen until 70 million years from now.
Continue reading “From the way These Stars Look, a Supernova is Inevitable”
Type Ia supernovae are an important tool for modern astronomy. They are thought to occur when a white dwarf star captures mass beyond the Chandrasekhar limit, triggering a cataclysmic explosion. Because that limit is the same for all white dwarfs, Type Ia supernovae all have about the same maximum brightness. Thus, they can be used as standard candles to determine galactic distances. Observations of Type Ia supernova led to the discovery of dark energy and that cosmic expansion is accelerating.
Continue reading “White Dwarf Measured Before it Exploded as a Supernova”
White dwarfs have some surprisingly strong magnetic fields, and one team of astronomers may have finally found the reason why. When they cool, they can activate a dynamo mechanism similar to what powers the Earth’s magnetic field.
Continue reading “How can White Dwarfs Produce Such Powerful Magnetic Fields?”
Astronomers have developed a new technique to search for exoplanets – by looking for their crushed up bones in the atmospheres of white dwarfs. And it’s working.
Continue reading “White Dwarf Atmospheres Might Contain the Pulverized Crusts of Their Dead Planets”
Can the galaxy’s dead stars help us in our search for life? A group of researchers from Cornell University thinks so. They say that watching exoplanets transit in front of white dwarfs can tell us a lot about those planets.
It might even reveal signs of life.
Continue reading “James Webb Will Look for Signs of Life on Planets Orbiting Dead Stars”
Astronomers recently spotted a rare type of supernova explosion that was accompanied by a massive flare of ultraviolet radiation. Untangling the mystery of the UV flash could help unravel the mysterious nature of these supernova explosions, and even help us understand the age of the universe.
Continue reading “There’s a flash of ultraviolet just as a white dwarf is exploding as a supernova”
Supernovae are some of the most powerful events in the Universe. They’re extremely energetic, luminous explosions that can light up the sky. Astrophysicists have a pretty good idea how they work, and they’ve organized supernovae into two broad categories: they’re the end state for massive stars that explode near the end of their lives, or they’re white dwarfs that draw gas from a companion which triggers runaway fusion.
Now there might be a third type.
Continue reading “A Star had a Partial Supernova and Kicked Itself Into a High-Speed Journey Across the Milky Way”
In their nuclear hearts, stars fuse elements heavier than hydrogen, creating the ingredients necessary to make planets, oceans, and people. Tracing the origins of individual elements in the Milky Way has been a challenge, but a new analysis of white dwarf stars reveals that they may be responsible for one of the most essential elements of all: carbon.
Continue reading “White dwarfs are a big source of carbon in the Universe”