Research articles

Realistic three-dimensional magneto-thermal simulations of magnetars with strong, large-scale toroidal magnetic fields accurately describe the observed light curves of 10 out of 19 magnetars in quiescence and allow their rotational orientation to be further constrained.

A shape evolution model shows that bilobed Arrokoth obtained its peculiar flattened shape by sublimation-driven mass loss. This process happened very early in the body’s history and may be a widespread shaping mechanism of Kuiper belt objects.

An asteroseismic and spectroscopic analysis of lithium-rich stars improves their classification based on the distributions of lithium, nitrogen and mass, and reveals that most of these evolved stars are red clump rather than red giant branch stars.

A five-membered carbon ring molecule, cyanocyclopentadiene, has been detected in a molecular cloud at a higher abundance than expected. This result from the GOTHAM survey indicates a rich aromatic chemistry in molecular clouds that is not fully understood theoretically.

MARSIS provides enhanced coverage of the south polar region where there have been indications of a subglacial lake. These new data confirm the presence of a lake and suggest the existence of a complex hydrologic system including various smaller liquid bodies, probably composed of salty brines.

Low-frequency quasiperiodic oscillations in X-ray data are thought to trace the accretion flow in X-ray binaries. Here, the detection of 200 keV oscillations probes the innermost regions of MAXI J1820+070, revealing the precession of a small-scale jet.

In situ measurements from the Rosetta spacecraft reveal the presence of atomic emissions close to comet 67P’s nucleus. Such emissions are due to dissociative excitation of molecules by the interaction with the solar wind, identifying them as a form of aurora.

Laboratory spectra of dust/ice aggregates are comparable to those observed in astrophysical environments, questioning the traditional onion-like layered ice model. According to observational spectra, such icy mixtures could harbour water ice in the diffuse interstellar medium, as well as in low-temperature circumstellar environments.

Six bright boulders of exotic material on near-Earth asteroid (101955) Bennu stand out from the average asteroidal surface. This unexpected record of impactors offers clues to the formation history of Bennu.

The Hayabusa2 team has discovered two types of bright boulder on the dark, carbonaceous asteroid Ryugu. One type has a spectrum consistent with material from an anhydrous silicate-rich asteroid, likely introduced by one or more collisions in Ryugu’s past.

Multi-band high-resolution observations reveal very fast and bursty nanojets. These nanojets are a consequence of the slingshot effect from magnetically tensed, curved magnetic field lines reconnecting at small angles, resulting in coronal heating.

The optical follow-up and analysis of two neutron star–black hole merger candidates with the Zwicky Transient Facility did not yield viable counterparts. However, state-of-the-art kilonova models constrain the ejecta properties of these mergers.

The detection of ~20 ppb of phosphine in Venus clouds by observations in the millimetre-wavelength range from JCMT and ALMA is puzzling, because according to our knowledge of Venus, no phosphine should be there. As the most plausible formation paths do not work, the source could be unknown chemical processes—maybe even life?

LTT 9779 b is Neptune-sized planet rotating around its star with a period of 0.79 days and an equilibrium temperature of 2,000 K. It is not clear how it retained its atmospheric envelope, which contains ~10% of H/He, as it should have been photoevaporated by now.

Three different layers can be distinguished in the first 500 metres of depth beneath the South Pole–Aitken basin on the Moon: a first layer made up by regolith and ejecta material from different craters, followed by a middle unit of mare basalts and finally a >200-m-thick layer of ejecta from the Leibnitz crater.

The detection of Lyman continuum emission with a high escape fraction from a low-mass clumpy galaxy at z = 1.42, in a redshift range where previously no similar sources were detected, opens up a new window to constrain the shape of the ionization spectrum.

Multi-decade observations of Jupiter’s stratospheric temperatures show that their quasiperiodic oscillation locked into a new period after a major atmospheric perturbation in 1992, from 5.7 years to 3.9 years. This is different from Earth (and presumably from Saturn), where the period returned to its original value after substantial atmospheric disruptions.

Ten years of gamma-ray data reveal emission in the vicinity of the microquasar SS 433 that is co-spatial with an interstellar gas enhancement and varies periodically at the precessional period of SS 433, challenging existing theoretical models.

Far-infrared polarimetric observations reveal a transition parallel to the gas flow in the orientation of magnetic field lines in the Serpens South molecular cloud, allowing gravitational collapse to occur even in the presence of strong magnetic fields.

High-resolution gravity data from Dawn’s second extended mission could probe the global and local structure of Ceres’s crust. The results show significant spatial and vertical variations of crustal density and porosity, associated with ice features and ice-related processes driven from the interior, and impacts.