White Dwarf

Shrouded in ash: New type of star discovered Space

Shrouded in ash: New type of star discovered

Most stars follow the main sequence of the Hertzsprung-Russell diagram in their life cycle. This is because they fuse certain elements in each part of their life, starting with hydrogen, followed by helium. Only particularly large or small stars deviate from this, or binaries that, for example, get fresh material from their neighbors despite their small size. But there are deviations from the rule, and lots of them. A team of German astronomers led by Klaus Werner of the University of Tübingen has discovered another exception. To do so, the researchers took a closer look at the light from white…
A planet that has outlived its star Life

A planet that has outlived its star

Located 117 light-years from Earth, the star WD1054-226 is a white dwarf - the remnant of a star the size of our Sun that has reached the end of its life. It's about the size of Earth, but about as heavy as the Sun. And it's hot: 20,000 to 30,000 Kelvin on the surface, 20 million Kelvin inside. Fusion processes no longer take place, but it takes about 10 billion years for it to cool down completely - our sun has only been around for five billion years. During this time, of course, a habitable zone can form around…
Supernova due to overeating Space

Supernova due to overeating

Actually, a type Ia supernova is pretty nasty. The star that will eventually perish has basically done everything right and ended its long, modest life as a white dwarf. As such, it could continue to watch its fellow stars burn up for many billions of years - longer than the universe is old - if it didn't have a younger partner that was still in the prime of its life. Because if material flows from this other star to our white dwarf, an overshooting reaction likes to happen. The (former) white dwarf can no longer cope with the inflowing…
The giant and the dwarf Astrophysics

The giant and the dwarf

Size alone is not always the most important factor. Sometimes, large things also orbit small things – because the details of a system matter. Astronomers have now found a real example for this situation in space, about 80 light-years from us, using the TESS telescope. The discovery published in Nature shows the likely presence of a planet the size of Jupiter orbiting the white dwarf, WD 1856+534, once every 34 hours. “This planet is roughly the size of Jupiter, but it also has a very short orbital period – one year on this planet is only 1.4 days long, so…