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The surprising presence of several very wide binary systems of the Kuiper belt can be explained by the gradual widening of initially tighter binaries by the gravitational effects of passing bodies.

It is widely believed that the Milky Way is set to collide with Andromeda, its nearest neighbour. New calculations using data from Hubble and Gaia that account for the effects of other galaxies show an almost 50% chance of our Galaxy avoiding this fate.

Compact exoplanetary systems masses have a similar mass ratio compared to the host star’s mass. Here, authors propose that these planets are surviving remnants of planet accretion during the end stages of stellar infall.

Hydrogen escape has contributed to Mars’s progressive aridity, but current hydrogen loss rates cannot explain inferred past water abundances. A three-dimensional model shows that during periods of increased axis tilt, hydrogen loss rates were up to ten times higher than present values.

Extremely high-resolution simulations reveal that interstellar medium-type turbulence significantly deviates from classical magnetized turbulence models.

An alternative model challenges the conventional view of isolated protoplanetary disks. Providing insights into angular momentum in supersonic turbulence, it shows that disk sizes are determined by mass captured from the environment.

The stacking of nearly three-quarters of a million spectra has unearthed a previously unknown component of the Galactic halo: a widely distributed, neutral, excited hydrogen layer that could harbour a sizeable proportion of the Milky Way’s baryons.

Data-driven workforce models predict that if the status quo is maintained, the fraction of women astronomers at all levels of academia will be below 30% for at least 60 years. Even if affirmative action were adopted, the gender gap would persist for another 25 years.

High-resolution images from the Hubble Space Telescope show evidence of star cluster migration and merger in dwarf galaxies.

Binary black hole mergers have recently been observed through the detection of gravitational wave signatures. The authors demonstrate that their association with active galactic nuclei can be made through a statistical spatial correlation.

Sudden bursts of charged particles emitted from the surface of the Sun can disrupt the satellites orbiting Earth. However, the mechanisms that drive these so-called coronal mass ejections remain unclear. An advanced computer model now establishes a link between the onset of an ejection and the emergence of magnetic flux into the solar atmosphere.

The neural network Self2Self is applied here to denoising large astronomical images. On test images, it performs quickly and enhances the appearance of weak signals.

State-of-the-art computer simulations show that the first water in the Universe formed in primordial supernova remnants 100 Myr after the Big Bang, enriching future sites of planet formation to levels that were nearly those in the Solar System today.

Three-dimensional simulations of the convective envelopes of massive stars suggest that it is the helium opacity that controls outbursts in luminous blue variable stars.

A magnetohydrodynamic model is able to explain the peak brightness point offset variations in the atmosphere of the hot giant exoplanet HAT-P-7 b with wind variability. A minimum field strength of 6 G is required to reproduce the observations.

Physical origin of accretion states in black hole X-ray binary systems is an open question. Here, the authors perform self-consistent radiative plasma simulations of the corona around the inner accretion flow and demonstrate natural generation of the observed hard and soft state X-ray emission when the plasma is turbulent.

How a star cluster manages to produce γ-rays at a ___location 30 light yr away from itself is a mystery that can be solved by carefully testing theories about how charged particles travel through space.

The mechanisms that sustain turbulence in a molecular cloud are not well understood. Using magnetohydrodynamic simulations, the effects of stellar winds on a cloud are studied, finding that energy can be efficiently transferred in magnetic waves generated by this stellar ‘feedback’.

During reconfinement in unmagnetized relativistic jets, a centrifugal instability develops that leads to a turbulent state. This instability likely lies behind the division of active galactic nuclei jets into the two Fanaroff–Riley classes.

Modelling of planetary formation reveals that asymmetries in the temperature rise associated with accretion produce a torque that counteracts inward migration, suggesting how the conditions for giant-planet formation may arise.

In laboratory experiments, strong magnetic fields at the boundary of a plasma can be generated by means of laser-wakefield acceleration, enabling the study of magnetization processes in scaled versions of astrophysical plasmas.

Simulations help reveal the complex relationship between the changing structure of the magnetic field lines and the plasma in the corona of the Sun, which is one hundred times hotter than the surface itself.

Estimates of parameters of strong gravitational lenses are obtained in an automated way using convolutional neural networks, with similar accuracy and greatly improved speed compared to previous methods.

The narrow rings seen in some debris disks, thought to be evidence for hidden exoplanets, might instead be caused by gas–dust interaction and a recently identified photoelectric instability.

The properties of 'dwarf' galaxies have long challenged the cold dark matter (CDM) model of galaxy formation, as the properties of most observed dwarf galaxies contrast with models based on the dominance of CDM. Here, hydrodynamical simulations (assuming the presence of CDM) are reported in which the analogues of dwarf galaxies — bulgeless and with shallow central dark-matter profiles — arise naturally.

Existing models of type Ia supernovae generally explain their observed properties, with the exception of the sub-luminous 1991bg-like supernovae. It has long been suspected that the merger of two white dwarfs could give rise to a type Ia event, but simulations so far have failed to produce an explosion. Here, a simulation of the merger of two equal-mass white dwarfs is presented that leads to a sub-luminous explosion; it requires a single common-envelope phase and component masses of about 0.9 solar masses.

High-resolution simulations show that dynamos can generate organized fields at high conductivity in the form of propagating dynamo waves.

When general relativity is included in large-scale simulations of the cosmic structure of the Universe, relativistic effects turn out to be small but measurable, thus providing tests for models of dark matter and dark energy.

Simple analytic estimates and detailed numerical calculations show that the solar dynamo begins near the surface, rather than at the much-deeper tachocline.

Machine learning-based surrogate models are important to model complex systems at a reduced computational cost; however, they must often be re-evaluated and adapted for validity on future data. Diaw and colleagues propose an online training method leveraging optimizer-directed sampling to produce surrogate models that can be applied to any future data and demonstrate the approach on a dense nuclear-matter equation of state containing a phase transition.

A state-of-the-art simulation reveals that the long-lasting 10 MK plasma in solar active regions can be heated by magnetic reconnections driven by continuous flux emergence that repeatedly deposit impulsive heating into the coronal plasma.

A dynamo mechanism similar to that in the Sun can produce the large-scale magnetic field that is needed to drive the relativistic outflows (and short gamma-ray burst) from binary neutron star mergers, according to a numerical relativity simulation.

Supergranules are large-scale convective features observed on the solar surface. Helioseismic inferences show that supergranular downflows appear to contribute less mass flux than upflows because they may be spatially too small to be detected. This challenges standard theories of solar convection.

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 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 application of physics-informed neural networks enables an estimation of the solar coronal magnetic field in quasi real time. A comparison with extreme-ultraviolet observations reveals that the model provides a realistic approximation and the modelled coronal field has a clear relationship with flaring activity.

Three-dimensional simulations of massive star convection show that core-convection-driven gravity wave oscillations at the surface of the star are not the source of ‘red noise’ seen in photometric observations. The search for the source continues.

Tides on the star MACHO 80.7443.1718 are so extreme that they crash and break every close passage in the pair of stars’ elliptical orbit. Models show how these breaking tidal waves create a rapidly rotating, shock-heated circumstellar atmosphere every periapse passage.

Using the POSYDON population synthesis code, this study predicts the existence of massive, thirty-solar-mass black-hole binaries in Milky-Way-like galaxies, challenging previous theories.

The origins of the pair of X-ray bubbles, called eROSITA bubbles (eRBs), detected in the halo of Milky Way are debated. Here, the authors show hydrodynamical simulations suggesting circumgalactic medium wind model can explain asymmetric eRBs.

High-resolution simulations of the small-scale dynamo (SSD) mechanism, with close-to-realistic parameters of deep stellar convection zones, indicate that SSDs are possible in the Sun and other cool stars, in contrast to previous theoretical expectations.

Models for night sky brightness are used to characterize sites for astronomical observatories, but in the presence of artificial light pollution, certain assumptions regarding aerosol shapes mean that the estimates are systematically underestimated, particularly at low altitudes.

The James Webb Space Telescope may detect and distinguish a young galaxy that hosts a direct-collapse black hole and nearby massive metal-free star formation at redshift 15 with as little as a 20,000-second total exposure time across four filters.

A three-dimensional radiation-hydrodynamic simulation of a tidal disruption event (TDE) flare from disruption to peak emission shows how deterministic predictions of TDE light curves and spectra can be calculated using moving-mesh hydrodynamics algorithms.

A convolutional neural network trained with mock galaxy cluster maps is applied to real maps from the Planck satellite, successfully predicting the masses of over 1,000 observed clusters and finding a 15% bias in masses measured directly from Planck.

The classical stellar evolution concept assumes that when the stars arrive on the main sequence, there is no traceable mark remains about their early evolutionary history. Here, the authors show that the accretion history leaves an imprint on the interior structure of the stars that are potentially detectable via asteroseismology.

Advanced LIGO has detected gravitational waves from two binary black hole mergers, plus a merger candidate. Here the authors use the COMPAS code to show that all three events can be explained by a single evolutionary channel via a common envelope phase, and characterize the progenitor metallicity and masses.