Search

Methane emission from a very cool brown dwarf, perhaps arising from an aurora, has been detected in James Webb Space Telescope observations.

The Gaia database is used to identify stars from which astronomers on orbiting planets could see Earth transiting the Sun in the past, present and future.

The hydroxyl radical OH has been detected in a planet-forming disk exposed to ultraviolet radiation and in a rovibrationally excited state. These JWST observations, when coupled with quantum calculations, reveal the ongoing photodissociation of water and its reformation in the gas phase.

The extensive water plume that originates from Enceladus and extends up to 40 Enceladus radii is mapped and characterized by JWST. Data suggest a sustained and uninterrupted plume activity spanning decades and a surface dominated by crystalline H₂O ice. No other molecules were detected in gaseous form.

Observations from the JWST MIRI/LRS show the detection of SO₂ spectral features in the 5–12-μm transmission spectrum of the hot, Saturn-mass exoplanet WASP-39b, suggesting that photochemistry is a key process in high-temperature exoplanet atmospheres.

Wind tunnel experiments and numerical modelling reveal the existence of two distinct ripples on Earth: centimetre-scale impact ripples and decimetre-scale hydrodynamic ripples, akin to those in water and on Mars.

Frequent storms on the young Sun would have ejected energetic particles and compressed Earth's magnetosphere. Simulations suggest that the particles penetrated the atmosphere and initiated reactions that warmed the planet and fertilized life.

The number of small bubbles at the ice-water interface in a perennially ice-covered lake varies in response to changes in ice thickness leading to seasonal variations in the backscatter detected by synthetic aperture radar, suggests 4-year observational time series from Lake Untersee, Antarctica.

The reported optical properties of organic hazes produced in water-rich exoplanet atmospheres differ from those in nitrogen-rich atmospheres. Such differences have a detectable effect on the spectra, impacting interpretation of JWST observations.

Some lake basins in the polar regions of Titan may be craters from nitrogen vapour explosions due to past warming, according to analysis of their morphology in comparison to terrestrial explosion craters from magma–water interaction.

James Webb Space Telescope observations of Jupiter have unveiled the presence of a narrow and intense atmospheric jet in the equator of the planet near the tropopause. The jet’s speed of 500 km h⁻¹ doubles the speed of the lower clouds. This new jet aligns with temperature and wind oscillations in Jupiter’s stratosphere.

On its way to Jupiter in 1990, the Galileo spacecraft searched for signs of life on Earth, providing a set of control experiments that continue to inform our quest to detect extraterrestrial life.

JWST observations of CH₃⁺ in a protoplanetary disk in the Orion star-forming region are reported showing that gas-phase organic chemistry in the interstellar medium is activated by ultraviolet irradiation and the methyl cation.

Time-series observations from the JWST of the transiting exoplanet WASP-39b show gaseous water in the planet’s atmosphere and place an upper limit on the abundance of methane.

The medium-resolution transmission spectrum of the exoplanet WASP-39b, described using observations from the Near Infrared Spectrograph G395H grating aboard JWST, shows significant absorption from CO₂ and H₂O and detection of SO₂.

The transmission spectrum of the exoplanet WASP-39b is obtained using observations from the Single-Object Slitless Spectroscopy mode of the Near Infrared Imager and Slitless Spectrograph instrument aboard the JWST.

The dayside thermal emission spectrum and brightness temperature map of the ultra-hot Jupiter WASP-18b obtained from the NIRISS instrument on the JWST showed water emission features, an atmosphere consistent with solar metallicity, as well as a steep and symmetrical decrease in temperature towards the nightside.

Transmission spectroscopy observations from the James Webb Space Telescope show the detection of carbon dioxide in the atmosphere of the gas giant exoplanet WASP-39b.

Acceleration of ‘Oumuamua is due to the release of entrapped molecular hydrogen formed through energetic processing of an H₂O-rich icy body, supporting the idea that it originated as a planetesimal relic similar to Solar System comets.

Optical observations of Dimorphos, a satellite of the asteroid 65803 Didymos, before, during and after the impact of the DART spacecraft, from a network of citizen science telescopes across the world are reported.

A nested orbit-to-ground approach for microbial landscape patterns at different scales, tested in the high Andes, provides a machine learning-based search tool for detecting biosignatures on terrestrial planets.

A broad-wavelength 0.5–5.5 µm atmospheric transmission spectrum of WASP-39b, a 1,200 K, roughly Saturn-mass, Jupiter-radius exoplanet, demonstrates JWST’s sensitivity to a rich diversity of exoplanet compositions and chemical processes.

Giant icy volcanos (cryovolcanos) on Pluto are unique in the imaged solar system and provide evidence for unexpected, active geology late in Pluto’s history.

Dust storms on Mars drive water escape to space. Here, the authors show the impact Martian dust storms have on the abundance of atmospheric hydrogen and oxygen, and how this helps to overall oxidize the Martian atmosphere.

Photochemical hazes in exoplanet atmospheres work as opacity barriers, hindering characterization of the atmospheres themselves. Here laboratory experiments quantify the haze surface energies that factor into the removal of hazes from atmospheres, which, when added to existing data on haze production, give a greater understanding of haze properties.

The habitability of a planet is defined at a fixed time. A bigger challenge is to understand how that habitability is sustained over geological timescales, and how the underlying processes compare across different planetary bodies.

A giant planet candidate roughly the size of Jupiter but more than 14 times as massive is observed by TESS and other instruments to be transiting the white dwarf star WD 1856+534.

Laboratory experiments show that the inclusion of even small quantities of sulfur in the atmospheres of exoplanets at 800 K significantly increases photochemical complexity, both in the vapour and in the solid phase: many sulfur gas products are created (including potential biosignature gases) and the production of organic haze particles increases threefold.

Icy planets and moons could become habitable as their host stars brighten and their ice melts. Climate simulations instead show a rapid transition from a snowball to an inhospitable greenhouse climate with significant water loss.

Common ground between human spaceflight and astrobiology can be used as the foundation for a new deal in the exploration of Mars that will allow stakeholders to reach critical astrobiological goals while supporting safer human exploration.

Two double-sun exoplanets have been discovered by the Kepler spacecraft, establishing a new class of ‘circumbinary’ exoplanets and suggesting that at least several million such systems exist in our Galaxy.

The unusual dark red coloration of Charon’s northern polar cap is shown to be produced from hydrocarbons that are cold-trapped from Pluto’s escaping atmosphere during winter.

A unified theory of particle transport by wind can explain the observations of aeolian features, like dunes, across the Solar System rocky bodies with atmospheres.

On 6 October 2008, a small asteroid designated 2008 TC3 hit the Earth in northern Sudan. Jenniskens et al. searched along the approach trajectory and luckily found 47 bits of a meteorite named Almahata Sitta. Analysis reveals it to be a porous achondrite and a polymict ureilite, and so the asteroid was F-class (dark carbon-rich anomalous ureilites).

The northern plains of Mars are thought to have harboured an ocean more than 3.6 billion years ago. Delta deposits and river-valley termini ring the proposed seabed and define an equipotential palaeoshoreline.

Exploring the hypothesis that life is present on Mars today is key to informing planetary protection issues at a pivotal time, with the clock ticking to return pristine samples before humans irrevocably alter the environment.

Ultrahot giant planet WASP-121b has a stratosphere that warms up with altitude during the day and cools down with altitude during the night. This trend is in agreement with predictions from circulation models in chemical equilibrium. Efficient vertical mixing hinders condensation of at least some refractory materials.

David Morrison finds contemporary echoes in a history of 'science wars', from Velikovsky to Lysenko and beyond.

High-resolution observations of the third largest asteroid, (2) Pallas, from SPHERE unveil a heavily cratered surface, probably due to Pallas’s inclined and eccentric orbit, a density almost equal to carbonaceous chondrites and hint at surficial salt-enriched spots.

SPHERE at the VLT observed Hygiea, the fourth largest body in the main belt and the parent body of a big asteroid family, at unprecedented spatial resolution. Its unexpected spherical shape without any impact crater is explained by numerical simulations with a big impact that fluidized the body, reassembling it in a rotational equilibrium regime.

A model of the Moon’s tidal evolution, starting from the fast-spinning, high-obliquity Earth that would be expected after a giant impact, reveals that solar perturbations on the Moon’s orbit naturally produce the current lunar inclination and Earth’s low obliquity.

Chariklo, Haumea and potentially Chiron are the only known ringed Solar System objects that are not giant planets. The rings of these minor bodies are relatively further from their hosts than those around giant planets; this increase is shown to be due to resonances driven by modest topographic features or elongations.

The Origins Space Telescope, one of four large Mission Concept Studies sponsored by NASA for review in the 2020 US Astrophysics Decadal Survey, will open unprecedented discovery space in the infrared, unveiling our cosmic origins.

Large periodic glacial outburst flood events replenish inorganic carbon concentrations and fuel the primary productivity of benthic microbial communities in the perennially ice-covered Lake Untersee.