James Stone started developing Athena in the mid-2000s, building on several years’ work on numerical methods for compressible magnetohydrodynamics in shocks. A couple of incarnations later, AthenaK is ready to face the exascale computing future.

The afterglows of gamma-ray bursts (GRB) are important signatures to study the origin of these energetic transient phenomena. GRB221009A is the brightest known GRB so far and relatively close to us at z = 0.151. The burst lasted almost 1,500 s and at peak its kinetic energy was ~1055 ergs (as compared to the typical 1050–1054 ergs). GRB221009A provided an opportunity to test our theories and push the

Most stars form in multiple systems, but because single stars are more straightforward to conceptualize and study theoretically and computationally, much of the research to date has been focused in that direction. In order to further develop understanding of how multiple systems form and evolve, observational examples of tertiary and higher-order systems have become sought-after study subjects. Jeong-Eun

Chandrayaan – which literally means Moon-craft – is India’s series of lunar exploration satellite missions. Chandrayaan-1 (CH1) was the first deep space mission of the series, launched in 2009. CH1, which carried NASA’s Moon Mineralogy Mapper, was pivotal in the discovery of water molecules locked in the form of minerals. Subsequently, CH2, launched in 2019, observed the Moon’s surface for the extent

It is no surprise that the exceptional TRAPPIST-1 system got a fair share of JWST time, focused on atmospheric characterization. The first observations of the two closest planets, b and c, tempered our expectations, as both were compatible with a bare rock or a very thin atmosphere. This result, based on the 15 µm CO2 absorption band measured by the MIRI spectrometer, is consistent with the hypothesis

The two Moon landing attempts of the Luna 25 and the Chandrayaan-3 missions in close succession are symbolic of the renewed international push to go back to the Moon on a more consistent basis, which is shaping up to be one of the main space exploration narratives of our time.

Chavez et al. have examined ~26 years’ worth of HST near-infrared observations with the WFPC2 and WFC3 instruments (see top row of the image, where monochrome images have been artificially coloured), along with archival observations from the W. M. Keck and Lick observatories that cover the period 1994–2022 in total. Clouds appear bright against the dark planetary disk, and are often smeared longitudinally

Being able to accurately identify extremely distant galaxies is a crucial step in exploiting JWST to its full potential and achieving some of its primary science goals. However, standard photometric methods to do this rely on fitting templates that are based on much lower-redshift conditions, potentially introducing biases and inaccuracies into the process. Charles Steinhardt and collaborators seek

Twelve Class 0 and seven Class I protostars were selected in nearby star-forming regions, enabling an angular resolution of 5–7 au. Three sources were found to have companions; one source was previously known to be a binary. The disks in these sources are embedded within their natal clouds, and careful separation of the disk emission is needed from background and foreground emission, requiring high

A new regular column, Access Code, makes its debut in this issue. Access Code will focus on computational astrophysics, and in particular the models and programs that have supported astrophysical discoveries over the past few decades.

None of the many telescopes coming in the next 10–15 years will be able in principle to perform a systematic atmospheric characterization of true Earth analogues — temperate rocky planets orbiting around G/K-type stars. The Habitable Worlds Observatory (HWO), an infrared/optical/ultraviolet 6 m telescope proposed as a top priority for NASA by the latest Decadal Survey on Astronomy and Astrophysics

As a consequence of the DART impact, a substantial amount of ejected material was thrown into space. This process removed kinetic energy from the system, and needs to be accounted for when Dimorphos’s remaining kinetic energy is determined. HST has been periodically observing Dimorphos since the collision with DART, and in a HST/WFC3 optical image from approximately 3 months post-impact, shown here

It shows a deep composite image taken by the Hubble Space Telescope and the DESI Legacy survey of the stellar tidal stream in tidal ring galaxy NGC 922. Examination of low-surface-brightness stellar structures in NGC 922 unveil complex umbrella-like features caused by interaction with nearby compact dwarf galaxy PGC 3080368 (or S2) — not seen in this image — along with the detection of a peculiar stellar

Neutrinos are produced in various astrophysical processes, such as nuclear reactions in the cores of stars, supernovae explosions, and high-energy phenomena like gamma-ray bursts and active galactic nuclei. The plane of the Milky Way — being a host of many of these high-energy events — is expected to be a significant source of neutrinos. The IceCube Neutrino Observatory has now observed evidence of

With the retirement of Ariane 5, Europe lost its only heavy-lift rocket — one that carried most of ESA’s fleet of large astronomy missions. The long-term future of independent access to space for Europe is not straightforward and can complicate the European space exploration roadmap.

Gary Ferland has been developing the photoionization code Cloudy for 45 years. The model has steadily been expanding in its coverage of parameter space, and focuses on the microphysics of irradiated environments.

Recently, NASA scientists and administrators have proposed a numerical scale for quantifying the Confidence of Life Detection — the CoLD scale1. Although the stated goal is to minimize damaging public trust with premature or overly confident claims of detecting life beyond Earth, the CoLD scale is an inapt and easily abused tool that will do little to address the misleading terminology and sensational

Early JWST results on high-redshift galaxies have attracted a lot of press and much debate, but other areas of astronomy and astrophysics are also uncovering new understanding about the Universe with JWST, albeit with less of a fanfare.

The authors use a terrestrial global climate model to compare scenarios that differ only by the eccentricity (e), choosing the values e = 0 (circular orbit) and e = 0.4. The results show that the eccentric model has ~3 times the hydrogen and water loss than the circular case, the corresponding boost to the amount of water vapour in the upper atmosphere making the effects of clouds more significant

Tidal disruption events (TDEs) are cataclysmic astronomical phenomena that occur when a star comes too close to a supermassive black hole (SMBH), resulting in the star being torn apart by immense gravitational forces. Although TDEs are tracers of emission from the outflows or jets coming from close to the SMBHs, their broadband-radio detection is rare. In their article, Adelle Goodwin and colleagues

Planetary evolution models and indirect observational evidence indicate that the architecture of the Solar System just after formation was substantially different from the current one, due to an early dynamical instability that rearranged the configuration of the giant planets. Some models suggest that we had five or six giant planets before one or two of them were ejected in the upheaval. It is assumed

Fast radio bursts (FRBs) fall into two observational categories: those that repeat and those that are not seen to repeat. In the current sample of FRBs (O(103)) just 1 in every 14 bursts has been observed to repeat, but potentially all FRBs emit repeat bursts, with those after the first evading detection. There are no clear (astro)physical differences between the two categories, but there are hints