white dwarf star tagged posts

In a first for white dwarfs, the burnt-out cores of dead stars, astronomers have discovered that at least one member of this cosmic family is two faced. One side of the white dwarf is composed of hydrogen, while the other is made up of helium.

“The surface of the white dwarf completely changes from one side to the other,” says Ilaria Caiazzo, a postdoctoral scholar at Caltech who leads a new study on the findings in the journal Nature. “When I show the observations to people, they are blown away.”

White dwarfs are the scalding remains of stars that were once like our sun. As the stars age, they puff up into red giants; eventually, their outer fluffy material is blown away and their cores contract into dense, fiery-hot white dwarfs...

This image from the NASA/ESA Hubble Space Telescope features the spectacular galaxy NGC2442, nicknamed the Meathook galaxy owing to its extremely asymmetrical and irregular shape.

This galaxy was host to a supernova explosion spotted in March 2015, known as SN2015F, that was created by a white dwarf star. The white dwarf was part of a binary star system and siphoned mass from its companion, eventually becoming too greedy and taking on more than it could handle.

This unbalanced the star and triggered runaway nuclear fusion that eventually led to an intensely violent supernova explosion.

The supernova...

Only 55 million lightyears away, this is one of the closest supernovae discovered in recent years. Credit: Image courtesy of University of California – Santa Barbara

In the 2009 film “Star Trek,” a supernova hurtles through space and obliterates a planet unfortunate enough to be in its path. Fiction, of course, but it turns out the notion is not so farfetched. Using the nearby Las Cumbres Observatory (LCO), astrophysicists from UC Santa Barbara have observed something similar: an exploding star slamming into a nearby companion star. What’s more, they detected the fleeting blue glow from the interaction at an unprecedented level of detail...