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In the coming months, the world is set to witness an extraordinary celestial event as a massive explosion in the T Coronae Borealis star system is poised to create a “new star” in the night sky. This rare astronomical event, expected to occur between now and September 2024, is not the birth of a star but rather an extraordinary nova outburst from T Coronae Borealis (T CrB), situated 3,000 light-years away in the constellation of Corona Borealis. NASA described the anticipated nova outburst as a “once-in-a-lifetime viewing opportunity” as T Coronae Borealis is predicted to become as bright as the...

Explanation: In 185 AD, Chinese astronomers recorded the appearance of a new star in the Nanmen asterism. That part of the sky is identified with Alpha and Beta Centauri on modern star charts. The new star was visible to the naked-eye for months, and is now thought to be the earliest recorded supernova. This deep telescopic view reveals the wispy outlines of emission nebula RCW 86, just visible against the starry background, understood to be the remnant of that stellar explosion. Captured by the wide-field Dark Energy Camera operating at Cerro Tololo Inter-American Observatory in Chile, the image traces the...

Astronomers have used a planet-hunting satellite to see a white dwarf abruptly switching on and off for the first time. The researchers led by Durham University, UK, used NASA's Transiting Exoplanet Survey Satellite (TESS) to observe the unique phenomenon. White dwarfs are what most stars become after they have burned off the hydrogen that fuels them. They are approximately the size of the Earth, but have a mass closer to that of the Sun. The white dwarf observed by the team is known to be accreting, or feeding, from an orbiting companion star. With the new observations astronomers saw it...

Almost 35 years ago, scientists made the then-radical proposal that colossal hydrogen bombs called novae go through a very long-term life cycle after erupting, fading to obscurity for hundreds of thousands of years and then building back up to become full-fledged novae once more. A new study is the first to fully model the work and incorporate all of the feedback factors now known to control these systems, backing up the original prediction while bringing new details to light. Published this week in the journal Nature Astronomy, the study confirms that the novae we observe flashing throughout the universe represent...

Dr. Tremblay said: "This is the first direct evidence that white dwarfs crystallise, or transition from liquid to solid. It was predicted fifty years ago that we should observe a pile-up in the number of white dwarfs at certain luminosities and colours due to crystallisation and only now this has been observed....The Sun itself will become a crystal white dwarf in about 10 billion years."

Scientists at Lawrence Livermore National Laboratory in California suspect that midsize black holes might be just the right size to provide enough gravitational force to reignite a dead white dwarf star — the stellar corpse of a star that's about the mass of the sun and that's used up its nuclear fuel. To test their idea, the team members ran supercomputer simulations of dozens of different close-encounter scenarios between these dead stars and midsize black holes. Every time a white dwarf got close to the Goldilocks black hole, the star reignited. The gravitational force from the black hole would cause the...

CAPE CANAVERAL, Fla. – A white dwarf star in the Constellation Virgo turns out to be a "death star" worthy of "Star Wars." Astronomers announced Wednesday that they have discovered a rocky object coming apart in a death spiral around this distant star. They used NASA's exoplanet-hunting Kepler spacecraft to make the discovery, then followed up with ground observations. "This is something no human has seen before," said Andrew Vanderburg of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, the lead author. "We're watching a solar system get destroyed," he said in a statement.

The ‘slow boat’ to Centauri concept we’ve discussed before in these pages envisions generation ships, vessels that take thousands of years to cross to their destination. And based on current thinking, that’s about the best we could manage with the propulsion systems currently in our inventory. Specifically, a solar sail making a close solar pass (a ‘sundiver’ maneuver) could get us up to 500 or 600 kilometers per second (0.002c), making a 2000-year journey to the nearest star possible. It’s hard to imagine under what circumstances such a mission might be launched.But let’s think long-term, as Greg Matloff (New York...

HERE IS THE STORY. A black activist commissioner in Dallas County was upset in a meeting by the use of the term "black hole." I called the Commissioners Court and asked for Commissioner Price. They connected me with his secretary, Melanie. We had a nice friendly conversation. It is not racist, and I am not afraid to say it, but her voice indicated that she was a black lady. MELANIE: Commissioner Wiley. DFU: Yes, ma'am, I'm Doug and I'm calling from California about the story of the black hole and Commissioner Wiley. M: Yes, sir. (sort of a little...

A debris disk spied recently around a distant dead star is likely the remains of an asteroid that was vaporized when the star died, scientists say. The discovery, detailed in the Dec. 22 issue of the journal Science, could be a sign of what will happen in our own solar system in a few billion years. Because the crushed asteroid was probably gravitationally lassoed in by one or more planets, the finding also provides evidence that planetary systems can form around massive stars. While analyzing the light spectra of several hundred white dwarfs, astronomer Boris Gänsicke of the University of...

The star in question is a white dwarf known as SDSS1228+1040. It is located 463 light-years away from Earth and is in the constellation Virgo... Gänsicke points out that there has been much debate within the realm of astrophysics about whether these short stellar life spans provide the "time that is necessary to form planets from the debris of the disk that made the star in the first place." ...The new findings suggest they are. And if these short-lived stars are able to support planetary systems of their own, they can certainly serve as models for what could happen billions...

A new discovery is casting doubt on the idea that a type of star explosion shines with equal brightness wherever it occurs in the universe. The finding could have implications for estimates of the size of the cosmos. Type-1a supernovae are typically used as standard indicators of distance in the vast expanse of the universe. But the discovery of a Type-1a supernova more massive than was thought possible could force astronomers to rethink their ideas about the luminous objects, scientists reported today. ... It was thought that all Type-1a supernovae emit equal amounts of light at their peak and fade...

Long before the Bible's tale of Jonah being swallowed by a whale, a small wannabe star has emerged intact after being engulfed by a neighboring giant star, scientists say. The victim was a brown dwarf, a failed star too small to sustain the nuclear reactions that ignites regular stars. The purpetrator was a red giant, an ancient star that once resembled our Sun but which puffed up to enormous size after its hydrogen fuel was depleted. The red giant has since expelled most of its gas into space and transformed into a dense, Earth-sized star called a white dwarfs. Using...

The biggest ever diamond has been found floating in space. The gem, estimated at close to 10 billion trillion trillion carats, is at the core of a dead star (BPM 37093) - a crystallised white dwarf. The newly-discovered diamond in the sky is a whopping great chunk of crystallised carbon 50 light-years from the Earth in the constellation Centaurus. It is 2,500 miles across (the moon is approximately 2,200 miles across) and weighs 5 million trillion trillion pounds. It has been dubbed "Lucy" in reference to the Beatles' song, "Lucy in the Sky with Diamonds". Diamond specialists told the research...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2004 January 11 NGC 2440: Cocoon of a New White Dwarf Credit: H. Bond (STScI), R. Ciardullo (PSU), WFPC2, HST, NASA Explanation: Like a butterfly, a white dwarf star begins its life by casting off a cocoon that enclosed its former self. In this analogy, however, the Sun would be a caterpillar and the ejected shell of gas would become the prettiest of all! The above cocoon, the...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2003 July 18 The Planet, the White Dwarf, and the Neutron StarCredit: H. Richer (Univ. British Columbia), et al. NASA, NOAO Explanation: A planet, a white dwarf, and a neutron star orbit each other in the giant globular star cluster M4, some 5,600 light-years away. The most visible member of the trio is the white dwarf star, indicated above in an image from the Hubble Space Telescope, while...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2003 May 31 NGC 1818: Pick A Star Credit: R. Elson and R. Sword (IoA Cambridge), NASA Explanation: This is NGC 1818, a youthful, glittering cluster of 20,000 stars residing in the Large Magellanic Cloud, 180,000 light-years away. Pick a star. Any star. Astronomers might pick the unassuming bluish-white one (circled) which appears to be a hot newly formed white dwarf star. What makes it so interesting? The...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2003 March 14 DEM L71: When Small Stars Explode Credit: J. Hughes, P. Ghavamian and C. Rakowski (Rutgers Univ.) et al., CXC, NASA Explanation: Large, massive stars end their furious lives in spectacular supernova explosions -- but small, low mass stars may encounter a similar fate. In fact, instead of simply cooling off and quietly fading away, some white dwarf stars in binary star systems are thought to...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2003 January 13 The Dumbbell Nebula in Hydrogen and Oxygen Credit & Copyright: George Jacoby (NOAO) et al., WIYN, AURA, NOAO, NSF Explanation: The first hint of what will become of our Sun was discovered inadvertently in 1764. At that time, Charles Messier was compiling a list of "annoying" diffuse objects not to be confused with "interesting" comets. The 27th object on Messier's list, now known as M27...

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2002 November 8 NGC 6369: The Little Ghost Nebula Credit: Hubble Heritage Team, NASA Explanation: This pretty planetary nebula, cataloged as NGC 6369, was discovered by 18th century astronomer William Herschel as he used a telescope to explore the constellation Ophiuchus. Round and planet-shaped, the nebula is also relatively faint and has acquired the popular moniker of Little Ghost Nebula. Planetary nebulae in general are not at all...