Tag

Exoplanets

All articles tagged with #exoplanets

space11 hours ago•12 min saved

DMS hints on a distant ocean-world exoplanet spark debate over life signals

K2-18b, a sub-Neptune about 124 light-years away, is a leading Hycean candidate that could harbor a global ocean beneath a hydrogen-rich atmosphere. Webb observations yielded two tentative signals of dimethyl sulfide, a gas commonly linked to marine life on Earth, but independent analyses question whether DMS was truly detected, leaving the existence of a biosignature on the planet unresolved and highlighting the need for more data and standardized detection criteria.

via Space Daily|

#biosignature #dimethyl-sulfide #exoplanets

space12 hours ago•10 min saved

Webb detects two-faced WASP-121b: scorching dusk and cloudy dawn

JWST mapped WASP-121b’s atmosphere longitude by longitude during a single transit as the planet rotated, revealing a hotter, expanded evening limb with water dissociation and a cooler morning limb possibly hosting silicate clouds; this rotational‑transit effect shows strong day–night circulation on this ultra-hot Jupiter (dayside ~2770 K, nightside ~1000 K) and highlights how limb-averaged spectra can miss key chemistry and cloud features.

via Space Daily|

#atmospheric-circulation #clouds #exoplanets

space18 hours ago•12 min saved

Sub-Neptunes Could Forge Oceans from Within

A Nature study shows that many planets called sub-Neptunes can synthesize their own water deep inside, by hydrogen in their thick atmospheres reacting with molten rock to produce H2O. If common, this could make water much more widespread in the galaxy and not just delivered by comets or asteroids. However, the water forms interiorly and may not always become a surface ocean, and these results are experimental/theoretical, requiring integration into formation models and observational tests to assess implications for habitability.

via Space Daily|

#exoplanets #magma-ocean #planetary-chemistry

science1 day ago•11 min saved

First Rogue Planet Mass Measured Confirms Galactic Population of Free-Floaters

Astronomers using a microlensing event observed from Earth and Gaia have measured both the mass and distance of a rogue planet about 9,800 light-years away, finding it Saturn-mass and confirming that the Milky Way hosts billions to possibly trillions of such starless worlds; the result leverages mass-distance measurements previously difficult for rogue planets and points to future surveys by the Roman Space Telescope to uncover many more.

via Space Daily|

#exoplanets #gaia #microlensing

science1 day ago•20 min saved

Cosmic cotton candy: two Jupiter-sized exoplanets revealed as featherweight 'super-puffs'

Astronomers have identified two Jupiter-sized exoplanets, TOI-791 b and TOI-791 c, about 1,100 light-years away, that are ultralow-density 'super-puffs,' with densities far lower than Jupiter and likely hydrogen/helium atmospheres. Their puffiness, comparable to shaving foam or cotton candy, makes them some of the lightest known planets and challenges standard formation theories. Observations from Antarctica helped determine their densities, and their orbits may be in a mean-motion resonance, implying formation in gas-rich regions farther from their star.

via Metro.co.uk|

#astronomy #exoplanets #science

space2 days ago•102 min saved

Roman Space Telescope nears liftoff with wide-field mission ahead

NASA’s Nancy Grace Roman Space Telescope sits in a Kennedy Space Center clean room ahead of its Aug. 30 liftoff; with a field of view at least 100 times larger than Hubble, Roman will study dark matter and dark energy while directly imaging distant exoplanets.

via Space|

#dark-matter #exoplanets #launch

science3 days ago•51 min saved

TESS uncovers Gaia23bra b via microlensing, a planet hidden in the data

NASA’s TESS has detected Gaia23bra b, a planet about 1.6 times Jupiter’s mass orbiting a distant orange-dwarf star roughly 40,000 light-years away, using gravitational microlensing—an effect predicted by Einstein’s general relativity. Hints of Gaia23bra b first appeared in Gaia data in 2023; microlensing provides a complementary route to exoplanet discovery alongside the transit method, and NASA’s Roman Space Telescope will use this technique to find about 1,000 microlensing planets in the Milky Way.

via Yahoo|

#exoplanets #gaia23bra-b #gravitational-microlensing

space3 days ago•15 min saved

Roman Space Telescope could census exoplanets across the galaxy in one mission

NASA’s Nancy Grace Roman Space Telescope, slated for launch on August 30, 2026, could detect tens to hundreds of thousands of exoplanet signals (roughly 60k–200k transiting planets, with ~100k often cited) via microlensing toward the Galactic bulge and high-cadence transit monitoring, creating a galaxy-wide planetary census rather than a simple list of confirmed worlds. Many detections will be planet candidates needing follow-up; the mission aims to map how planet populations vary with distance from the galactic center and environment, complementing Kepler and other missions. Roman features a 2.4-meter mirror, a wide field of view, a 300-megapixel infrared camera, and will operate from the Sun–Earth L2 point, including a coronagraph demonstration for direct-light studies.

via Space Daily|

#exoplanets #galactic-bulge #microlensing

space4 days ago•104 min saved

Einstein-powered microlensing uncovers a distant exoplanet in TESS data

NASA's TESS has detected Gaia23bra b using gravitational microlensing—a method based on Einstein's general relativity—marking a rare microlensing planet found in TESS data. Hints first appeared in Gaia data in 2023; Gaia23bra b weighs about 1.6 Jupiter masses and orbits an orange-dwarf star roughly 40,000 light-years away, far beyond TESS's typical transit range. This discovery shows microlensing can reveal planets that transit methods miss and foreshadows Roman Space Telescope-led microlensing surveys, which could uncover many more such worlds.

via Space|

#exoplanets #gaia23bra-b #general-relativity

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•107 min saved

NASA gears up for robotic servicing of its alien-hunting Habitable Worlds Observatory

NASA’s Habitable Worlds Observatory (HWO), a future space telescope to study rocky, Earth-like planets, is being designed as serviceable in space—likely via robotics at the Sun–Earth L2 point about a million miles away—so instruments and detectors can be swapped and upgraded over time (including gamma-ray detectors). Building on Hubble’s servicing model, the plan could even involve in-space assembly if needed, with the mission still in early design stages and a launch target in the 2040s.

via Space|

#exoplanets #habitable-worlds-observatory #nasa

space5 days ago•4 min saved

Nearby Super-Earth Could Harbor Life in Red Dwarf's Habitable Zone

A refined analysis places GJ 3378b at about 2.3 Earth masses with a 21‑day orbit, situating it in the habitable zone of a nearby red-dwarf star about 25 light‑years away. Detected with infrared radial velocities using the Habitable-zone Planet Finder on the Hobby‑Eberly Telescope, the discovery highlights red dwarfs as fertile ground for rocky, potentially life-bearing worlds, though stellar activity and a possibly thin atmosphere complicate habitability. Upcoming observatories like GMT, ELT, and the Habitable Worlds Observatory could enable direct observations and biosignature searches to assess its true habitability.

via Universe Today|

#exoplanets #gj-3378b #habitable-zone

space6 days ago•12 min saved

Earth-like planets: the vast gap between potential habitats and thriving biospheres

The debate over how many Earth-like worlds exist spans more than twenty orders of magnitude: optimistic estimates, based on eta-Earth from Kepler data, suggest up to hundreds of quintillions of Earth-size planets in the habitable zone across the observable universe, while the Rare Earth hypothesis argues complex life may be extremely rare and Earth could be unique. These figures answer different questions—how many worlds could plausibly host life vs. how many actually foster a biosphere like ours—and depend on uncertainties in eta-Earth, the galaxy count, and what “Earth-like” truly means. The true number lies somewhere in between, and future telescopes aiming to detect atmospheres may help narrow the gap between possibility and reality.

via Space Daily|

#earth-like-planets #eta-earth #exoplanets

space7 days ago•25 min saved

Salt Clouds Redefine the Pink Planet’s Cold Atmosphere

Astronomers using the James Webb Space Telescope have detected salt clouds in the atmosphere of the cold exoplanet GJ 504 b (the Pink Planet), explaining its spectral signature and prompting revised models of cloud chemistry for distant, frigid worlds; the planet, about 57 light-years away and first discovered in 2013, shows a mix of water vapor, methane, carbon dioxide and ammonia that only fits when salty clouds are included in atmospheric simulations.

via New York Post|

#astronomy #exoplanets #james-webb-space-telescope

space8 days ago•103 min saved

Nearby Habitable-Zone Exoplanet Sparks Life-Hopes

Astronomers refined the mass and orbit of GJ 3378b, a 2.3‑Earth-mass exoplanet around a nearby red dwarf about 25 light-years away in Camelopardalis. With a 21-day orbit, it sits in the star’s habitable zone and could be rocky, but its atmosphere and true habitability remain uncertain because it does not transit its star. Atmosphere confirmation awaits future instruments like the Habitable Worlds Observatory (targeted for the 2040s) and JWST observations, all while red-dwarf radiation poses challenges—yet this nearby world is one of our best chances to study potentially habitable exoplanets.

via Space|

#exoplanets #gj-3378b #habitable-zone