Tag

Jwst

All articles tagged with #jwst

space2 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

science3 days ago•6 min saved

JWST Finds Shared, Unknown Chemical Fingerprint on Titan and Pluto

NASA's JWST detected the same unidentified absorption feature in Titan and Pluto spectra, suggesting a surface- or near-surface compound common to both nitrogen- and methane-rich worlds. The signal, stronger on Pluto and not explained by known absorbers, appears to originate from the surfaces rather than the atmosphere and was observed by two different JWST instruments, making an instrumental glitch unlikely. Researchers consider possibilities from an unknown compound to a known molecule in an unusual form, with future observations and Dragonfly mission data hoped to help identify it; findings are published in Astronomy & Astrophysics and archived on arXiv.

via ScienceAlert|

#astrochemistry #jwst #pluto

science3 days ago•5 min saved

JWST Finds Mysterious Absorption Signature on Pluto and Titan

The James Webb Space Telescope detected a 5.113‑micrometer absorption feature on both Pluto and Titan that cannot be matched to any known compound in spectral databases, suggesting a mysterious mixture or a chemistry not yet characterized. Researchers confirm it isn’t an instrument error and are pursuing laboratory replication and further JWST observations, with the Dragonfly mission potentially helping identify candidate compounds to solve this outer-solar-system puzzle.

via WIRED|

#astrochemistry #jwst #pluto

space4 days ago•14 min saved

Rock Clouds Wake in the Morning, Clear at Night on Distant Gas Giant, JWST Finds

JWST observations of WASP-94A b reveal a day-night atmospheric cycle: the planet’s morning limb is cooler and cloudier due to mineral silicate clouds forming at low pressure, while the evening limb is hotter and clearer with stronger water absorption. The clouds form and evaporate as air circulates from night to day and back, a rock-based weather system on a tidally locked gas giant about 700 light-years away. This limb-resolved spectroscopy highlights why averaging spectra can mislead about atmospheric composition and demonstrates JWST's ability to map exoplanet weather.

via Space Daily|

#clouds #exoplanets #jwst

space4 days ago•104 min saved

Interstellar Comet 3I/ATLAS Carries Fossil Clues From a Distant Disk

New isotope measurements from JWST and the VLT corroborate that interstellar comet 3I/ATLAS formed billions of years ago far from its parent star, likely in the outer regions of a protoplanetary disk (akin to a Kuiper belt) and was later ejected into interstellar space. Its carbon-12 to carbon-13 and nitrogen-14 to nitrogen-15 ratios differ markedly from solar-system comets, suggesting a birth environment and chemistry unlike our own. The findings were published in Nature Astronomy.

via Space|

#3iatlas #interstellar #isotopes

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

science4 days ago•2 min saved

Hidden Molecule Behind the 5.11-Micrometer Signature on Pluto and Titan

JWST observations reveal a missing 5.11‑micrometer absorption band in the spectra of both Pluto and Titan, suggesting an as-yet unidentified molecule on their surfaces. After searching prior data, researchers couldn’t find a match for the feature, though candidates such as allenes or benzene-related species are considered; no definitive identification has been made. The findings appear in a paper accepted by Astronomy & Astrophysics and linked as an arXiv preprint, with follow-up JWST data and NASA’s Dragonfly mission to Titan anticipated to help solve the mystery.

via Gizmodo|

#jwst #pluto #science

astronomy7 days ago•4 min saved

Bullet Cluster Results Put MOND Back in Spotlight, Questioning Dark Matter Proof

A James Webb Space Telescope analysis of the Bullet Cluster suggests Modified Newtonian Dynamics (MOND) can explain the observed gravitational lensing with less or differently distributed invisible mass, challenging the traditional view that the cluster provides definitive evidence for dark matter and prompting a reevaluation of DM claims.

via Universe Today|

#astronomy #bulletcluster #darkmatter

space8 days ago•12 min saved

Ancient galaxy defies early-growth limits, seen 290 million years after the Big Bang

JWST confirmed the galaxy JADES-GS-z14-0 at about z~14.3 (roughly 290 million years after the Big Bang), unusually large and bright for its age, and ALMA detected oxygen indicating heavy-element enrichment far earlier than models predicted—raising questions about how quickly the first galaxies assembled while not overturning the Big Bang framework.

via Space Daily|

#cosmology #early-universe #galaxies

space8 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

astronomy9 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

science12 days ago•5 min saved

JWST Unmasks a Pink Exoplanet With Salty Clouds

Using the James Webb Space Telescope, astronomers study the cold planetary-mass companion GJ504b and find a pink-hued atmosphere likely shaped by salty clouds (potentially potassium chloride or zinc sulfide) and a complex mix of gases. The spectral analysis suggests the object is more planet-like than a brown dwarf, marking a milestone in understanding dim, chilly worlds and highlighting clouds’ crucial role in interpreting their spectra.

via ScienceAlert|

#exoplanets #gj504b #jwst

space13 days ago•14 min saved

JWST Reveals Black Holes Ahead of Some Early Galaxies

JWST observations of the early universe show several systems where central black holes are already disproportionately massive or dominant compared with their hosts, challenging the traditional view that galaxies form first and then grow their central black holes. Notable cases include UHZ1 behind Abell 2744, where a black hole may be tens of millions of solar masses with a relatively small stellar host, and a strongly lensed z~7 object with a ~50 million-solar-mass black hole. These findings support heavy-seed/direct-collapse formation scenarios and/or rapid accretion, but mass estimates remain model-dependent and not all objects fit a single story. The broader takeaway is that multiple pathways likely governed early black hole–galaxy co-evolution, with black holes sometimes leading galaxy growth. Future spectra, X-ray data, lensing, and gravitational-wave observations will help distinguish true heavy seeds from apparent overgrowth due to compact, dusty hosts.

via Space Daily|

#astronomy #blackholes #earlyuniverse

science14 days ago•60 min saved

Mars organics, female Homo naledi, and water’s two-faced nature: this week's science roundup

NASA’s Perseverance has found the highest concentration of organic molecules yet in Jezero crater’s mudstones, hinting at fossilized microbes on Mars; archaeologists report that all Homo naledi remains from the Rising Star cave system in South Africa are female; new AI-assisted research suggests water may consist of two interchanging liquids, challenging a single-liquid view of the substance; JWST observations illuminate how early galaxies formed and evolved (dying young), and Euclid has produced the most detailed image of the Milky Way yet, with a separate note of a newly forming star in Orion.

via Yahoo|

#homo-naledi #jwst #mars