Search

2023 CX1 is the only L-chondrite-like asteroid analysed from space to ground. It catastrophically fragmented in the atmosphere, depositing 98% of its energy in one burst—an unusual, high-risk fragmentation mode with implications for planetary defence.

High-resolution ultraviolet and optical spectra of a large sample of comets show that Fe i and Ni i lines are ubiquitous, even when the comets are far from the Sun.

Analysis of data from multiple instruments reveals a giant exoplanet in orbit around the 0.2-solar-mass star TOI-6894. The existence of this exoplanetary system challenges assumptions about planet formation and it is an excellent target for atmospheric characterization.

Precise mass and radius measurements of giant planet WASP-193 b find an extremely low density of 0.059 ± 0.014 g cm⁻³. Current evolutionary models cannot fully explain such a low density, but the extended atmosphere makes WASP-193 b very suitable for high-precision characterization via JWST.

Hubble observations of the TRAPPIST-1 system exclude the presence of H₂-dominated cloud-free atmospheres for the three planets within or around the system’s habitable zone. This result supports the hypothesis that these planets are terrestrial in nature.

Combining the infrared capabilities of JWST and synthetic tracking techniques, the detection of some of the smallest asteroids ever observed in the main belt is reported; their large abundance reveals a population driven by collisional cascade.

The authors report on a temperate Earth-sized planet orbiting the cool M6 dwarf LP 791-18 with a radius of 1.03 ± 0.04 R_⊕ and an equilibrium temperature of 300–400 K, with the permanent night side plausibly allowing for water condensation.

The SPECULOOS project detected an Earth-sized planet in a short orbit around a nearby Jupiter-sized star. This planet, SPECULOOS-3 b, is one of the most promising rocky exoplanets for detailed emission spectroscopy characterization with JWST.

The icy dwarf planet Makemake has projected axes of 1,430 ± 9 and 1,502 ± 45 km and a V-band geometric albedo larger than Pluto’s but smaller than Eris’s, with no global Pluto-like atmosphere.

The authors report observations of a dense and inhomogeneous ring at a surprisingly large distance from the trans-Neptunian body Quaoar.

The Transiting Exoplanet Survey Satellite (TESS) has identified a nearby, bright, quiescent M dwarf star that hosts two sub-Neptune-sized planets and one super-Earth-sized planet. The system is eminently suitable for follow-up studies of transit timing variations, radial velocity measurements and transmission spectroscopy.

Orbital parameters for the seventh Earth-sized transiting planet around star TRAPPIST-1 are reported, along with an investigation into the complex three-body resonances linking every member of this planetary system.

Last year, three Earth-sized planets were discovered to be orbiting the nearby Jupiter-sized star TRAPPIST-1; now, follow-up photometric observations from the ground and from space show that there are at least seven Earth-sized planets in this star system, and that they might be the right temperature to harbour liquid water on their surfaces.

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.

A low-mass star that is just 12 parsecs away from Earth is shown to be transited by an Earth-sized planet, GJ 1132b, which probably has a rock/iron composition and might support a substantial atmosphere.

Observations of a stellar occultation by (10199) Chariklo, a minor body that orbits the Sun between Jupiter and Neptune, reveal that it has a ring system, a property previously observed only for the four giant planets of the Solar System.

Interstellar comet Borisov has thus far looked very much like a Solar System comet in terms of its volatile content, but with new data from ALMA that show robust detections of CO and HCN, it is clear that Borisov is rich in CO, helping to pinpoint its origin.

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.

The JWST has the potential to increase our understanding of terrestrial exoplanets and their atmospheres, but the various signal contaminations need to be isolated and quantified. Using JWST Cycle 1 observations of TRAPPIST-1 as a benchmark, this Perspective proposes a series of steps to use future JWST data efficiently for this purpose.

Hubble Space Telescope data show that interstellar comet 2I/Borisov has an unusually high CO/H₂O ratio—higher than any other comet that has been seen in the inner regions of our Solar System. This allows us to constrain the nature and location of the circumstellar region from which 2I/Borisov originated.