Tag

White Dwarf

All articles tagged with #white dwarf

space15 hours ago•7 min saved

Jupiter-sized survivor orbits a cooling white dwarf, defying expectations

Astronomers using the James Webb Space Telescope studied WD 1856 b, a Jupiter-sized planet that survived its Sun-like star’s red-giant phase and now orbits a cooling white dwarf about 75 light-years away. The eight-minute grazing transit revealed an atmosphere with methane and hazes, and a surprisingly hot around-400 K temperature, indicating internal reheating rather than just re-radiating energy from the star. The data favor a late inward migration caused by gravitational interactions with distant stellar companions over a common-envelope origin, suggesting more planetary survivors may await discovery near nearby white dwarfs.

via Ars Technica|

#gas-giant #jwst #planetary-migration

science1 day ago•5 min saved

Cold Milky Way Objects Might Be Alien Dyson Swarms Around Small Stars

A new study proposes that some of the Milky Way’s coldest objects, currently catalogued as stars, could be Dyson swarm energy collectors built by advanced civilizations around red and white dwarfs. Such systems would absorb visible light and re-emit heat as infrared, altering their position on the Hertzsprung–Russell diagram and creating distinctive, cleaner infrared spectra and irregular brightness changes. Astronomers are using JWST and projects like Hephaistos to search for these signatures and distinguish them from natural dust clouds.

via The Times of India|

#alien-megastructure #dyson-swarm #infrared-signature

space4 days ago•13 min saved

Webb Reveals Atmosphere on a Jupiter-sized World Orbiting a White Dwarf

NASA’s James Webb Space Telescope detected an atmosphere around WD 1856 b, a Jupiter-sized planet that orbits the Earth-sized white dwarf WD 1856+534—marking the first atmospheric detection for a world around a dead star. Transmission spectroscopy during a transit revealed hydrocarbons, likely methane, plus a hazy cloud layer and a faint glow from the planet’s night side, indicating residual heat. The planet, about 80 light-years away, completes a close 34-hour orbit and is roughly seven times wider than its star, suggesting a past heating event and likely inward migration after the star’s transformation. The team plans additional Webb transits to better pin down its chemistry and formation history.

via Space Daily|

#jwst #methane #space

space9 days ago•104 min saved

JWST spots a Jupiter-sized world dancing around a white dwarf, hinting at our Sun’s distant fate

Astronomers using the James Webb Space Telescope observed WD 1856 b, a Jupiter-sized exoplanet transiting a white dwarf about 80 light-years away. The planet completes an ultra-tight 1.4-day orbit and is hotter than expected, likely due to past heating during the star’s red giant phase or inward migration. The team proposes two possible migration scenarios and notes that JWST’s capabilities enable studying planets orbiting stellar remnants, offering a forward look at the solar system’s distant future. The findings, published in Nature, also highlight the challenge of catching such a transit, which lasts about eight minutes.

via Space|

#exoplanet #james-webb-space-telescope #planetary-migration

space9 days ago•191 min saved

Giant planet around a dead star offers a peek into our solar system’s future

Astronomers using the James Webb Space Telescope have spotted WD 1856 b, a Jupiter-sized exoplanet orbiting a dead white dwarf about 80 light-years away. The planet completes a 34-hour orbit at under 2 million miles from its star, with atmospheric methane detected and a temperature around 127°C, suggesting the planet migrated inward after the star died; two proposed histories—the engulfment of the planet by the star or gravitational interactions with other bodies—could explain its current orbit, though heating timing favors migration after death. This system offers a preview of how giant planets might survive and evolve when their host stars die, hinting at the distant fate of Jupiter and Saturn in our own solar system.

via CNN|

#exoplanet #jwst #planetary-migration

space9 days ago•8 min saved

JWST Discovers a Planet’s ‘Second Life’ Around a White Dwarf

Using JWST, scientists observed WD 1856b, a giant planet about 82 light-years away that orbits a white dwarf, finding its atmosphere and surprisingly high temperature (~126 C) and mass (~7 Jupiter masses). The system features the deepest known exoplanet transit (56%), and the results suggest a “second life” for giant planets after their star dies—potentially heated by a nearby binary—and open a new field of post-main-sequence planetary atmospheres, while the idea of a rocky planet in a white-dwarf habitable zone remains speculative.

via ScienceAlert|

#exoplanet #jwst #planetary-atmospheres

astronomy10 days ago•64 min saved

Methane, aerosols and a warm nightside on a planet circling a white dwarf

JWST/NIRSpec PRISM transmission spectra of WD 1856 b, a Jupiter-sized planet transiting a nearby white dwarf, reveal methane and other hydrocarbons, a scattering aerosol haze, and a nightside thermal emission. The atmosphere is metal-rich (CH4 at a few percent to ~7–20% in retrievals) with an opaque cloud deck near 100 mbar, and the planet’s nightside temperature is about 390–412 K, much warmer than the 160 K equilibrium expected for this system. Mass is constrained to ~4.3–10.9 Jupiter masses. The data imply a reheating event during migration into the white dwarf phase, most consistent with high-eccentricity migration and tidal circularization rather than common-envelope evolution, offering a rare window into the fate of giant planets around Sun-like stars after stellar death.

via Nature|

#aerosols #astronomy #exoplanet-atmosphere

science10 days ago•53 min saved

JWST reveals planets may survive their star’s death

A James Webb Space Telescope study of the Jupiter‑sized exoplanet WD 1856 b orbiting a white dwarf shows that planets can survive the death of their star and even migrate inward, with measurements of its mass, temperature, and atmosphere suggesting past heating during the star’s red‑giant phase. This provides a forward glimpse into our solar system’s fate: in about 5 billion years the Sun will become a red giant, likely destroying the inner planets (Mercury, Venus, possibly Earth) while more distant worlds may endure in altered orbits, illustrating that stellar death can reshape—but not necessarily end—planetary systems.

via Yahoo|

#earth #james-webb-space-telescope #science

gaming11 days ago•14 min saved

Dawn of War IV returns in White Dwarf 526 with exclusive interview, decals, and a Chaos–Cathay Battle Report

White Dwarf issue 526 centers on the Dawn of War IV revival, including an exclusive interview with Creative Director Jan Theysen, a free transfer sheet with over 350 decals for Gabriel Angelos and the Blood Ravens, and a step-by-step painting guide for their crimson color scheme. The issue also features a Genestealer Cults showcase by Mark Kilburn and a World of Legend Battle Report where Chaos advances on Grand Cathay, teased by Miao Ying and the new Warriors of Chaos miniatures, plus coverage of Ciaphas Cain’s new miniature and pre-order/subscription details for White Dwarf 526.

via Warhammer Community|

#ciaphas-cain #dawn-of-war #gaming

space13 days ago•112 min saved

Earth May Outlive the Sun: A Delicate Cosmic Tug-of-War Could Spare Our World

New stellar-evolution models and observations of a nearby dying star suggest Earth could survive the Sun’s giant phases if solar mass loss dominates over tidal forces, allowing Earth to move outward rather than be engulfed. Mercury and Venus are still expected to meet a fiery end, but the outcome hinges on how much mass the Sun will lose—an uncertainty researchers are currently trying to resolve, with future missions like PLATO expected to help. A Letter to the Editor in Astronomy & Astrophysics outlines these calculations and the remaining questions about Earth’s ultimate fate.

via Live Science|

#earth #planetary-fate #space

gaming13 days ago•19 min saved

Old World Core Set Launches with 54 Miniatures

Warhammer Community previews next week’s pre-orders for Warhammer: The Old World’s Core Set—a 54-miniature starter (22 Chaos Warriors, 32 Grand Cathay) with a revised rulebook, Battle March content, and Common Magic Items/Lores of Magic card packs; also a Made to Order line and the Battle March: General’s Companion. The Middle-earth Strategy Battle Game expands with The Burning of the Westfold, Riders of Rohan, Warriors of Rohan, and Hill Tribesmen Commanders; White Dwarf 526 and Flames of Betrayal (Black Library) are highlighted, along with Warhammer TV content. Pre-orders run next week with a UK window through 13 July 2026, and regional delays are noted (Korea).

via Warhammer Community|

#core-set #gaming #middle-earth-strategy-battle-game

science19 days ago•7 min saved

Astronomers Link Repeating Radio Bursts to a Close White Dwarf–Red Dwarf Binary

Using ASKAP, researchers pinpointed the source of long-period radio transients to a tight magnetic white dwarf–red dwarf binary (ASKAP J1745-5051). The ~1.368-hour orbital period matches the ~1.345-hour radio repetition, while X-ray data show a ~1.32-hour cycle; radio bursts are elliptically polarized and linked to magnetic accretion regions, distinct from the X-ray emitting zone—making this system a key reference for understanding LPTs.

via WIRED|

#askap-j1745-5051 #binary-star #long-period-radio-transients

space19 days ago•95 min saved

Sun's Final Dance: Plasma Kicks Could Push It Across the Solar System

New research suggests Sun-like stars don’t simply fade away as they die; during the red-giant phase they eject plasma in asymmetric bursts that give the star tiny opposite-direction kicks. Over hundreds of thousands of years this creates a random-walk movement, with a Sun-like star experiencing thousands of such kicks and moving at a few thousand kilometers per hour. While the effect is subtle, it could help push the Sun’s outer layers to around Mars’ orbit, engulfing the inner planets in about five billion years, and it can also disrupt wide binary systems. In rarer cases, kicks might propel a star toward a companion, causing a collision. The findings from Caltech’s Jim Fuller (and colleagues) were presented at the American Astronomical Society meeting and submitted for publication.

via Space|

#astronomy #plasma-ejection #red-giant

science19 days ago•5 min saved

T Coronae Borealis: The Naked-Eye Nova Could Happen Any Moment

Astronomers say the 3,000-light-year binary system T Coronae Borealis could erupt as a nova soon. The red giant–white dwarf pair accretes gas until a thermonuclear runaway brightens the system to naked-eye visibility for about two days; predictions for 2024 missed the mark due to uncertainties in the accretion rate, but the eruption is considered imminent by some researchers. The last outburst was in 1946, and observers continue to monitor the system for a potential event in the coming months to years.

via CBC|

#binary-star #nova #red-giant

science26 days ago•2 min saved

Stellar Rosetta Stone unlocks mystery of galactic radio signals

Astronomers identify a tight white dwarf–red dwarf binary, ASKAP J1745−5051, as the source of certain long-period galactic radio transients. Magnetic interactions in the system generate regular radio bursts and accretion-driven X-ray emission, offering a 'stellar Rosetta Stone' to decode these signals and help distinguish their origins, while providing a natural laboratory for extreme plasma and magnetic-field physics.

via BBC Science Focus Magazine|

#binary-star-system #long-period-radio-transients #magnetic-interactions