Articles

Astronomical research facilities, such as space telescopes, space probes or ground-based observatories, are the largest contributor to an astronomer’s carbon footprint, well beyond other activities such as flying to conferences or running computer simulations.

Fragment #443 of the Luna 16 sample is of extra-lunar origin. It was probably delivered from an LL chondrite asteroid around 1 Gyr ago, directly as a micrometeorite or as a result of a bigger impact, and never experienced temperatures higher than 400 °C since its formation. Its characteristics are compatible with a stony parent body coming from the Flora family.

An axion cloud surrounding a spinning black hole would rotate the electric vector position angles of linearly polarized emissions. Tight constraints on the axion–photon coupling can therefore be obtained from polarization information in the Event Horizon Telescope’s images of M87^⋆.

Nodes and filaments in the cosmic web have an impact on the metallicity of gas in a galaxy. This influence can be connected to the growth of dark-matter haloes and the chemical environment in which galaxies reside.

Seasonal changes in the correlation between O₂ and H₂O in comet 67P’s coma are indicative of two reservoirs of molecular oxygen in the nucleus, a deeper primordial one and a surficial one, suggesting that the observed high abundance of O₂ and its association with H₂O are not reflective of the original accretion source.

The galactic black hole binary GRS 1915+105 shows highly variable yet correlated X-ray and radio emission, implying that the corona and jet share an energy reservoir. This observation supports the idea that the corona may be a form of the jet.

The newly discovered eROSITA X-ray bubbles in the Milky Way’s centre, together with the Fermi bubbles and microwave haze, may be explained by a single episode of central supermassive-black-hole jet activity a few million years ago.

The EDGES team reported a measurement of the redshifted 21 cm absorption line of neutral hydrogen from the cosmic dawn. However, the SARAS 3 measurement of the radio sky spectrum now suggests that the EDGES detection might not have a cosmological source.

The range of timescales and luminosities measured from the nearby fast radio burst FRB 20200120E observationally connects these extreme extragalactic transients with studies of Galactic neutron stars.

Very early observations of a type Ia supernova—from within one hour of explosion—show a red colour that develops and rapidly disappears. These data provide information on the initial explosion mechanism: surface nuclear burning on the white dwarf or extreme mixing of the nuclear burning process.

A cosmological simulation shows that low-mass galaxies can form with far less dark matter than expected, with results matching some observed characteristics. Roughly one-third of massive central galaxies may host at least one such dark-matter-deficient satellite.

Using common interstellar chemical species (CO, C and NH₃), the authors show that peptides can be experimentally synthesized on a solid surface under interstellar conditions. The formation route circumvents the creation of amino acids in the pathway towards proteins.

A young and low-energy radio jet has cleared a substantial amount of gas from the central region of galaxy B2 0258+35, demonstrating the effectiveness of kiloparsec-scale feedback from radio-loud active galactic nuclei and supporting the predictions of simulations.

The distribution of the slowly rotating, blue fraction of main-sequence stars in the colour–magnitude diagram of young star clusters, and their peculiar mass function, imply that they may originate from binary star mergers.

A method to measure the complexity of planetary signals from remote-sensing observations is presented. Tests using Earth observations point to a correlation between increasing complexity and the presence of an extensive biosphere, showing the potential of this agnostic method to identify promising targets for life.

A 4.8σ exomoon candidate is found around gas giant Kepler-1708 b, which orbits at 1.6 au around its star. It is the only candidate from a dedicated survey that analysed 70 cool giant exoplanets discovered by Kepler. Kepler-1708 b-i has a radius of 2.6 Earth radii and orbits its planet at 12 planetary radii.

The planetary architecture of the Solar System and its isotopic dichotomy can be reproduced using a protoplanetary disk model structured with rings and gaps, as commonly seen in protoplanetary disks around other stars.

Observations of some so-called ‘water fountain’ stars show that they appear to have lost a large fraction of their initial mass in a very short time (hundreds of years). This leads Khouri et al. to suggest that these sources have undergone the poorly understood process of common-envelope evolution, where the envelope of one star engulfs that of its companion.

Magnetospheres of exoplanets are vast, tenuous and hard to detect. Deep blue-shifted absorption lines observed in the extended region around HAT-P-11 b may provide evidence for a magnetosphere and magnetotail.

This Article reports the detection of oscillations in the massive star β Crucis using polarized light. Such oscillatory modes provide information about stellar structure; in this case the stellar mass, inclination of the rotation axis and size of the convective core.