Latest White dwarf Stories

Explosions of small stars, long thought to create stellar dust, actually sweep dust away, scientists discovered. For years, researchers have observed swirling dust clouds around systems called recurring novas, which periodically explode. New images of a distant nova have now overturned astronomers' long-standing assumption that the dust originates in the blasts. Scientists recently observed the RS Ophiuchi system, where a small white dwarf star and large red giant orbit each...

First results from a new NASA-funded scientific instrument at the W. M. Keck Observatory in Hawaii are helping scientists overturn long-standing assumptions about powerful explosions called novae and have produced the first unified model for a nearby nova called RS Ophiuchi. "We were getting ready for a routine engineering run when all of a sudden the nova went off. It was very bright and easy to observe, so we took this opportunity and turned it into gold," says team member Marc...

The Gemini South Multi-Object Spectograph (GMOS) recently captured a dramatic image of a vast cloud complex named DEM L316 located in the Large Magellanic Cloud. The peanut-shaped nebula appears to be a single object, but the latest research indicates that it is really comprised of two distinct gas and dust clouds formed by different types of supernova explosions.The new image reveals the intricate tendrils of gas and dust located in the remnants of the stellar explosions that created the...

GREENBELT, Md. - New observations from Suzaku, a joint Japanese Aerospace Exploration Agency (JAXA) and NASA X-ray observatory, have challenged scientists' conventional understanding of white dwarfs. Observers had believed white dwarfs were inert stellar corpses that slowly cool and fade away, but the new data tell a completely different story.At least one white dwarf, known as AE Aquarii, emits pulses of high-energy (hard) X-rays as it whirls around on its axis. "We're seeing behavior...

NASA's Hubble Space Telescope is providing strong evidence that white dwarfs, the burned out relics of stars, are given a "kick" when they form.The sharp vision of Hubble's Advanced Camera for Surveys uncovered the speedy white dwarfs in the ancient globular star cluster NGC 6397, a dense swarm of hundreds of thousands of stars.Before the stars burned-out as white dwarfs, they were among the most massive stars in NGC 6397. Because massive stars are thought to gather at a globular...

Astronomers may have found another way that stars evolveAstronomers have discovered white dwarf stars with pure carbon atmospheres. These stars possibly evolved in a sequence astronomers didn't know before. They may have evolved from stars that are not quite massive enough to explode as supernovae but are just on the borderline. All but the most massive two or three percent of stars eventually die as white dwarfs rather than explode as supernovae.When a star burns helium, it leaves...

Cambridge, MA - Astronomers at the Harvard-Smithsonian Center for Astrophysics (CfA) have found that a supernova discovered last year was caused by two colliding white dwarf stars. The white dwarfs were siblings orbiting each other. They slowly spiraled inward until they merged, touching off a titanic explosion. CfA observations show the strongest evidence yet of what was, until now, a purely theoretical mechanism for creating a supernova. "This finding shows that nature may be richer...

Using NASA's Swift and Rossi X-ray Timing Explorer (RXTE) satellites, astronomers have discovered one of the most bizarre planet-mass objects ever found.The object's minimum mass is only about 7 times the mass of Jupiter. But instead of orbiting a normal star, this low-mass body orbits a rapidly spinning pulsar. It orbits the pulsar every 54.7 minutes at an average distance of only about 230,000 miles (slightly less than the Earth-Moon distance)."This object is merely the skeleton of a...

The chemical fingerprint of a burned-out star indicates that Earth-like planets may not be rare in the universe and could give clues to what our solar system will look like when our sun dies and becomes a white dwarf star some five billion years from now.Astronomers from UCLA report that a white dwarf star known as GD 362, which is surrounded by dusty rings similar to those of Saturn, has been contaminated by a large asteroid that left more than a dozen observable chemical elements in the...

VLT Provides Evidence for Type Ia Supernovae ScenarioA unique set of observations, obtained with ESO's VLT, has allowed astronomers to find direct evidence for the material that surrounded a star before it exploded as a Type Ia supernova. This strongly supports the scenario in which the explosion occurred in a system where a white dwarf is fed by a red giant.Because Type Ia supernovae are extremely luminous and quite similar to one another, these exploding events have been used extensively as...