Research articles

The observation by the IceCube Neutrino Observatory of high-energy neutrinos from the Galactic plane indicates that the Milky Way is deficient in neutrinos, most probably because it has not hosted an active source for the past few tens of kiloyears.

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.

This work identifies a period structure in the radio emission of magnetars that can be observed in all classes of radio-emitting rotating neutron stars, regardless of their evolutionary history, their power source or their magnetic field strength.

This work finds a systematic offset of 5.5 ± 1.1 Myr between estimates of the ages of stars made with two popular techniques: isochronal fitting and dynamical traceback. This offset is proposed to represent the time a young star remains bound to its parental cloud before dispersing and could help to improve stellar evolutionary models.

Synchrotron and inverse-Compton emission provide evidence for a reverse-shock origin of the high-energy emission from a gamma-ray burst, GRB 180720B. The polarization of the optical emission originating from the reverse shock suggests a turbulent shock that is amplified by the magnetic field in the relativistic ejecta.

The Zhurong rover identified polygonal terrain at a depth of 35 m under Utopia Planitia on Mars. This finding suggests that the mid-latitudinal region experienced a cold and wet environment near the freezing point of water around the Hesperian–Amazonian transition, possibly induced by Mars’s high obliquity.

A supercomputer simulation shows that the strikingly varied distributions of different galaxy types across the Local Supercluster arise naturally in the standard models of cosmology and galaxy formation.

The ASTRO 3D Centre of Excellence achieved 50% women personnel over a 5 yr time-frame by implementing a suite of evidence-based recruitment and retention initiatives. These initiatives changed how postdoctoral researchers were recruited and helped to develop a supportive and positive culture.

Prolonged radio emissions above a sunspot, akin to those auroral emissions previously seen in the polar regions of planets and certain stars, have been detected using the Very Large Array. This detection could potentially provide support for an alternative mechanism for the origin of some stellar radio bursts.

Juno’s global infrared mapping of Jupiter’s moon Io determined the distribution as well as the energy output of its volcanoes. Spatial differences emerge, with the equator more active than the polar zones and more heat flow at the north pole than at the south, indicative of an uneven lithosphere.

Extremely low-mass stars, much less massive than the Sun, lack radiative cores—something that could affect their magnetic dynamos. This study reveals that these stars can have magnetic fields that are up to 30% stronger than those of Sun-like stars, implying fundamental differences in their internal magnetic structures.

ESA’s Trace Gas Orbiter reveals that the winter night sky on Mars emits visible light between 50 km and 70 km altitude in the polar regions. This nightglow should be observable with simple space camera systems and the naked eyes of future Mars astronauts.

A lensed quasar at redshift z ≈ 10.3, seen in X-rays, hosts a supermassive black hole of mass similar to that of its host galaxy. The large black-hole mass at a young age, as well as the amount of X-rays it produces, suggest that the black hole formed from the collapse of a huge cloud of gas.

The altered and thermally metamorphosed CY chondrites are shown to be the meteoritic analogue of asteroid Phaethon. This suggests that Phaethon’s activity is driven by gas released from the decomposition of near-surficial material heated at perihelion, whereas the interior is kept relatively unaltered and hydrated.

Juno’s close flyby of Ganymede on 7 June 2021 allowed the infrared mapping spectrometer JIRAM to observe the surface at unprecedented spatial resolution. JIRAM’s detailed spectroscopic characterization reveals past extensive aqueous alteration on the moon, possibly together with hydrothermal activity.

Late-phase spectroscopy reveals that explosive nucleosynthesis, occurring in a bipolar collimated configuration, is commonly found for core-collapse supernovae, highlighting the importance of asphericity in shaping these diverse cosmic fireworks.

Venus’s atmosphere is linked to its interior and can be used to infer the planet’s evolution. Observed atmospheric N₂, CO₂ and surface pressures are best explained by an early phase of plate tectonics, operating for at least 1 billion years.

Space interferometry reveals the hidden and filamentary internal structure of the relativistic jet in 3C 279 at microarcsecond angular resolution. These details challenge previous assumptions on the morphology and radio variability of blazars.

Using NASA’s Juno mission measurements, researchers obtain a new high-precision map of Jupiter’s gravity field and confirm that the planet’s observed strong east–west jet streams penetrate inwards in a direction parallel to the planet’s spin axis.

New northern aurora emissions on Uranus in the infrared spectrum are detected after a 30-year search. The emissions, observed close to equinox, are most likely caused by the 88% increase in upper atmosphere column density.