Tag

Jwst

All articles tagged with #jwst

space53 minutes ago•5 min saved

JWST Reveals an Airless, 30% Bigger Rocky World Orbiting a Red Dwarf

Using JWST's MIRI to measure mid-infrared emissions, scientists studied the rocky, tidally locked exoplanet LHS 3844b, about 50 light-years away. The dayside reaches around 1,000 K, and the spectrum implies a basaltic/mantle-like surface with little to no atmosphere, suggesting a Mercury-like, geologically inactive world rather than an Earth-like tectonically active planet. Researchers plan additional JWST observations to better constrain the crust and surface properties; the findings were published in Nature Astronomy.

via ScienceAlert|

#exoplanets #infrared-spectroscopy #jwst

science4 days ago•12 min saved

Two-Faced Weather on a Distant World Upends Exoplanet Chemistry

JWST’s limb-resolved spectroscopy of the tidally locked exoplanet WASP-94A b reveals a morning sky thick with vaporized magnesium silicate clouds (sand) and a clear evening sky, driven by strong equatorial winds that shuttle clouds from day to night. This two-hemisphere view shows that averaging light over the whole planet previously biased atmospheric readings, overestimating oxygen by ~100x; the corrected enrichment is only ~3–5x solar. The finding demonstrates that exoplanet atmospheres may be dynamic and two-faced, prompting a re-evaluation of many past measurements and encouraging limb-resolved studies on more worlds.

via Space Daily|

#clouds-and-winds #exoplanet-atmospheres #jwst

astronomy4 days ago•5 min saved

JWST spots wind-driven clouds cycling around a hot exoplanet 690 light-years away

The James Webb Space Telescope detected phase‑dependent cloud formation on the hot exoplanet WASP‑94 A b during transit, revealing thick clouds on the night side that form and dissipate as winds move them onto the day side; the clouds are likely mineral droplets due to dayside temperatures around 1,600 K, offering new insight into how exoplanetary atmospheres weather and rotate.

via Nature|

#astronomy #atmospheres #clouds

science5 days ago•7 min saved

JWST maps contrasting day-night weather on a distant hot gas giant

JWST studied WASP-94A b, a hot, tidally locked gas giant about 690 light-years away, using limb-resolved spectroscopy during transit to compare its morning and evening limbs. The morning limb is cloudier with high-altitude aerosols; the evening limb is clearer and shows water vapor, driven by strong equatorial winds and a day–night temperature difference around 450 K. Averaging the limbs biases atmospheric composition estimates (e.g., oxygen enrichment and metallicity), highlighting the need to account for day-night asymmetries in exoplanet studies and to refine models to mitigate these biases.

via Ars Technica|

#atmospheres #exoplanets #jwst

science7 days ago•11 min saved

JWST discovers surprisingly mature galaxies early, fueling debate on cosmic age

NASA’s James Webb Space Telescope has detected bright, massive galaxies at redshifts around 11–14 (within ~300 million years after the Big Bang) that contain heavy elements like oxygen, challenging standard galaxy-formation timelines. A minority peer‑reviewed paper even suggests a universe age of 26.7 billion years by combining ideas like tired light and time‑varying constants, but the mainstream view remains ~13.8 billion years; the JWST findings continue to test and possibly reshape our cosmological models.

via Space Daily|

#cosmology #early-galaxies #galaxy-formation

space8 days ago•8 min saved

JWST Survives a 344-Point Deployment Challenge on 1 Kilowatt of Power

NASA’s James Webb Space Telescope, parked at the Sun-Earth L2 point about 1.5 million kilometers from Earth, runs on roughly 1 kilowatt of power (with a solar array near 2 kW) and weathered a critical deployment sequence with 344 single-point failures—mostly tied to sunshield and mirror deployment. By January 2022, 295 of these were retired, leaving 49 primarily propulsion-related items. All 107 sunshield release devices fired and the 155 motors for aligning 18 hexagonal mirror segments operated, enabling Webb to begin its infrared observations with a remarkably power-efficient design.

via Space Daily|

#deployment #jwst #power

astronomy11 days ago•4 min saved

Webb Telescope Spots One of the Earliest Galaxies, Tracing the First Stars

Using the James Webb Space Telescope, astronomers captured LAP1-B, one of the universe’s earliest and faint galaxies, dating to about 13 billion years ago (roughly 800 million years after the Big Bang). Gravitational lensing by a foreground cluster amplified its light ~100x, enabling spectroscopy that reveals extremely low metal content and signatures of Population III stars, including a high carbon-to-oxygen ratio. The data also suggest the galaxy sits in a massive dark matter halo, offering critical clues about how the first galaxies formed and evolved in the early cosmos (Nature).

via The Daily Galaxy|

#astronomy #dark-matter #gravitational-lensing

space12 days ago•8 min saved

JWST Maps the Cosmic Web in Unprecedented Detail

Using NASA’s James Webb Space Telescope data from the COSMOS-Web survey—the telescope’s largest General Observer program—astronomers have created the most detailed map of the cosmic web to date, tracing the network of galaxies across 13.7 billion years of cosmic history back to when the universe was about 1 billion years old. The improvement comes from JWST’s deep infrared observations and precise galaxy distances, revealing filamentary structures that earlier maps smoothed over. The team is releasing the large-scale structure maps, a catalog of about 164,000 galaxies, and a video publicly for broader study of galaxy formation and cosmic evolution.

via futurity.org|

#astronomy #cosmic-web #cosmos-web

space12 days ago•5 min saved

JWST Discovers Hidden Bar and Potential Black Hole Duo in the Squid Galaxy

NASA's JWST infrared view of the nearby Squid Galaxy (M77/NGC 1068) uncovers a hidden central bar of stars, gas, and dust and tracks gas motions around a core mass of ~13 million solar masses—possibly a tight binary of supermassive black holes. The images also reveal a bright starburst ring and other star-forming regions along the spiral arms, and the galaxy has been linked to a high-energy neutrino detected in 2022, hinting it could be a giant particle accelerator. JWST can't resolve the black holes directly but will illuminate the nucleus's dynamics.

via ScienceAlert|

#black-holes #jwst #ngc-1068

science13 days ago•31 min saved

JWST Finds the Most Metal-Poor Galaxy Yet, a Fossil from Cosmic Dawn

James Webb Space Telescope spectroscopy of LAP1-B, a strongly lensed galaxy at zspec ≈ 6.63, reveals an ultra-faint, chemically primitive star-forming system with gas-phase oxygen abundance of ~4×10−3 Z☉—the lowest yet for a high-redshift galaxy. It hosts a hard ionizing radiation field inconsistent with enriched populations, shows an elevated C/O ratio suggesting metal-free/poor stellar origins, and has a stellar mass <3,300 M⊙ while its dynamical mass exceeds baryons, implying a dominant dark-matter halo. LAP1-B is a direct high-redshift progenitor of local ultra-faint dwarfs, providing a rare window into early galaxy formation.

via Nature|

#jwst #lap1-b #metallicity

science15 days ago•5 min saved

X-Ray Little Red Dot Hints at a Bridge in Early Black Hole Growth

Astronomers using JWST and Chandra found an unusual X-ray-bright “little red dot” (3DHST-AEGIS-12014) about 11.8 billion light-years away, suggesting it may be a transitional object linking black hole stars to the growth of early supermassive black holes. Its X-ray emission could escape through holes in surrounding gas clouds, explaining variability and offering a potential link between LRDs and SMBHs in the young universe, though further observations are needed to confirm the scenario and its implications for black hole formation.

via Universe Today|

#early-universe #jwst #little-red-dots

space18 days ago•3 min saved

New X-Ray Dot Could Reveal Hidden Phase of Early Black Hole Growth

NASA's Chandra and JWST data reveal an X-ray-emitting 'X-ray dot' among the enigmatic little red dots, suggesting a transient, ultra-massive black hole stage—possibly a 'black hole star' where a dense gas cloud hides emissions and links these dots to early black hole growth.

via Futurism|

#astronomy #blackhole #chandra

astronomy19 days ago•73 min saved

Twin Exoplanets Ride Inward Together, Rewriting Hot-Jupiter Origins

Astronomers using the James Webb Space Telescope studied TOI-1130, a system where a hot Jupiter (TOI-1130c) hosts a close companion mini-Neptune (TOI-1130b). The pair likely formed beyond the frost line and migrated inward together into a 2:1 resonance, with TOI-1130b showing a heavy atmosphere rich in water vapor, CO2, SO2 and methane. This rare architecture suggests hot Jupiters can form with companions and migrate as a pair, challenging prior ideas about planetary formation.

via Space|

#astronomy #exoplanets #hotjupiter

astronomy19 days ago•5 min saved

Behemoth Galaxy From 12 Billion Years Ago Defies Spin, Outnumbers Milky Way in Stars

The James Webb Space Telescope revealed XMM-VID1-2075, a massive galaxy from about 12 billion years ago with several times more stars than the Milky Way, yet showing no detectable rotation, challenging current ideas about early galaxy dynamics and suggesting a possible single high-energy interaction rather than multiple mergers.

via The Daily Galaxy|

#astronomy #early-universe #galaxy-formation

spaceastronomy20 days ago•87 min saved

Tiny Kuiper Belt World May Harbor a Real Atmosphere

Astronomers report evidence of a surprisingly thin atmosphere around the Kuiper Belt object (612533) 2002 XV93, a small icy body about 500 km across. If confirmed, the atmosphere would be extremely tenuous—roughly 5–10 million times thinner than Earth's—and may last under 1,000 years unless replenished. Independent verification is urged, with future JWST observations expected to help determine whether the atmosphere persists (suggesting a long‑term gas source) or fades (potentially from a recent impact).

via Live Science|

#astronomy #atmosphere #jwst