Tag

Exoplanets

All articles tagged with #exoplanets

space9 hours 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

science2 days ago•72 min saved

Earth-like cores may be the oddity in the galaxy's most common planets

A new study argues that the galaxy's most common planets—sub-Neptunes—may not have Earth-like layered interiors with a distinct metallic core and silicate mantle. If these planets accrete more than about 1% hydrogen by mass, hydrogen, iron, and silicate can mix into a single, homogeneous interior, changing how they cool, hold onto atmospheres, and evolve their radii. This could explain features like the radius gap and how radii relate to orbital period, and it offers testable predictions for JWST observations, though the model rests on extrapolations of material behavior under extreme pressures. In short, Earth-like cores might be the exception rather than the rule in the galaxy.

via Space|

#exoplanets #hydrogen-miscibility #planetary-interiors

astronomy5 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

space5 days ago•13 min saved

Venus-like exoplanets may outnumber Earths, researchers claim

Preliminary modelling presented at the EGU General Assembly suggests Venus-like, CO₂-dominated atmospheres on rocky exoplanets could be about twice as common as Earth-like worlds with oceans, though the results are not yet peer-reviewed and observational confirmation is lacking. Venus is the nearest planetary reference point, but it remains underexplored due to data gaps and shifting science priorities; confirming exoplanet Venus-like atmospheres will require future missions and more capable telescopes, with biases toward short-period planets complicating detection.

via Space Daily|

#atmospheres #exoplanets #note-ensure-only-five-tags-remove-one-perhaps-keep-five-venus-exoplanets-atmospheres-planetary-formation-space-exploration

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

space5 days ago•71 min saved

TESS Unveils Its Most Complete All-Sky Map of Exoplanets Yet

NASA's Transiting Exoplanet Survey Satellite (TESS) released its most complete all-sky mosaic, assembled from 96 sectors observed between 2018 and September 2025, mapping about 6,000 potential exoplanets (roughly 679 confirmed and 5,165 candidates). The mosaic highlights the diversity of worlds found, including a recently identified system with a super‑Earth and a tilted, eccentric companion and evidence of planet–planet collisions, marking the conclusion of TESS's second mission extension in Sept 2025.

via Space|

#all-sky #astronomy #exoplanets

science13 days ago•3 min saved

TESS Unveils the Most Complete All-Sky View of Exoplanets

NASA’s Transiting Exoplanet Survey Satellite (TESS) has released its most complete all-sky mosaic (96 sectors from 2018–Sept. 2025), showing about 679 confirmed exoplanets and 5,165 candidates; the image traces the Milky Way’s plane and demonstrates TESS’s ongoing success in finding diverse worlds, including possible habitable-zone planets, while total exoplanet confirmations across missions exceed 6,270.

via NASA Science (.gov)|

#all-sky-mosaic #exoplanet-candidates #exoplanets

space13 days ago•5 min saved

A 0.8 Earth-Radius Threshold Signals When Tiny Planets Lose Their Atmospheres

A new model called STEHM finds that planets smaller than about 0.8 Earth radii struggle to hold onto atmospheres due to weaker gravity and faster interior cooling, which suppresses outgassing; under common CO2 conditions, 0.6–0.5 R⊕ worlds can lose atmospheres in tens to hundreds of millions of years, while planets at or above 0.8 R⊕ retain thick atmospheres for billions of years. Exceptions exist for unusually high initial carbon, minimal core radius, or a cold start delaying outgassing. The study suggests using 0.8 R⊕ as a practical filter in planning future exoplanet observations and prioritizing targets for atmospheric characterization.

via Indian Defence Review|

#atmospheres #exoplanets #habitability

science13 days ago•16 min saved

AI-led scan hints at 10,000 hidden exoplanet candidates

A study using artificial intelligence on NASA’s TESS data identifies about 10,000 new exoplanet candidates beyond our solar system. While these are unconfirmed, the approach could speed up the search for potentially habitable worlds, adding to the thousands of known planets and thousands more awaiting verification.

via The Daily Beast|

#ai #arxiv #exoplanets

science15 days ago•8 min saved

Hubble Preps Roman for the Milky Way's Bulge Microlensing Hunt

Hubble's precursor imaging of the Milky Way's galactic bulge will calibrate and guide NASA's Nancy Grace Roman Space Telescope’s upcoming Galactic Bulge Time-Domain Survey, enabling precise mass measurements and a census of microlensing events, rogue planets, and compact objects, with six 72‑day seasons and high-cadence observations ahead of Roman's 2026 launch.

via NASA Science (.gov)|

#exoplanets #galactic-bulge #hubble-space-telescope

space19 days ago•6 min saved

Pandora's First Images Mark Milestone for Budget-Friendly Exoplanet Science

NASA's Pandora, a small, cost-efficient exoplanet mission, released its first engineering images, demonstrating precise pointing and infrared-visible observation capabilities as it targets atmospheric studies of 20 known exoplanets, aiming for multiple transits per planet from a Sun-synchronous orbit to advance understanding of exoplanet atmospheres.

via The Daily Galaxy|

#exoplanet-atmospheres #exoplanets #low-cost-missions

space19 days ago•4 min saved

Webb Maps Olivine-Rich Surface of Nearby Airless Super-Earth

JWST’s mid-infrared spectroscopy reveals LHS 3844 b, a rocky super-Earth about 50 light-years away, has a dark, olivine-rich crust with no detectable CO2 or SO2 and likely no atmosphere. The planet is roughly 30% larger than Earth, orbits its red dwarf in 11 hours, and is tidally locked, resulting in a scorching dayside and a barren surface. This demonstrates JWST’s ability to infer surface texture and geology of distant worlds, opening new possibilities for direct exoplanet terrain characterization via infrared data.

via Jalopnik|

#exoplanets #james-webb-space-telescope #lhs-3844-b

space19 days ago•3 min saved

Pandora Exoplanet Mission Unveils First Engineering Images, Pioneering Low-Cost Exoplanet Science

NASA's Pandora exoplanet mission released its first engineering images, validating a new, low-cost Pioneers Program approach with a two-instrument payload (CODA and the VISDA/NIRDA spectrograph) designed for simultaneous visible and near-infrared exoplanet observations. Launched Jan 11 in a Twilight rideshare, Pandora will monitor about 20 known transiting exoplanets (10 transits each) over roughly a year from a sun-synchronous, high-stability orbit, using these measurements to separate stellar variability from planetary atmospheres and search for water-rich conditions; the Jan 19 images show proper pointing and a functioning NIRDA cryocooler at ~110 K, and Aspera is planned for 2026 under the program's $20 million cost cap.

via Universe Today|

#astronomical-instrumentation #exoplanets #nasa

astronomy20 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

science21 days ago•6 min saved

JWST Reveals Basaltic, Airless Surface on Rocky Exoplanet LHS 3844 b

JWST’s infrared observations of the rocky exoplanet LHS 3844 b reveal a dark, airless basalt-like surface, suggesting it lacks Earth-like crust and significant water. The study proposes two surface scenarios—recent volcanism with a fresh basalt surface or a heavily space-weathered regolith—with current data favoring the latter due to the absence of sulfur dioxide. Further JWST observations will help distinguish surface texture and composition to resolve the ambiguity.

via Center for Astrophysics | Harvard & Smithsonian|

#exoplanets #geology #jwst