By studying the dynamical properties, age and metallicity of globular clusters in the inner Galaxy, the authors found evidence of a massive dwarf galaxy that was accreted by the Milky Way 1.8 billion years earlier than the Gaia-Sausage-Enceladus merger.

Is the Universe infinite in all directions? The only way to know is to look. This Review presents the status of investigations into the topology of the Universe, and looks ahead to upcoming opportunities.

The use of agentic large language models obviates human interpretation of scientific results, and will lead to substantial distrust in the literature.

Solar Orbiter’s detection of the ion composition of a magnetic switchback reveals its origin in hot coronal loops, implicating interchange reconnection as the release mechanism of the solar wind plasma, where it then propagates as an Alfvén wave.

Little red dots evolve from under-dense regions at z > 4 to typical environments by z ≈ 3.5, while their halo and stellar masses surge by a factor of ten. This accounts for their scarcity at low redshifts and suggests a distinct evolutionary path for little red dots compared with other active galactic nuclei.

Detailed models for the complete evolution of mass-transferring binary stars produce merging black holes consistent with the observed masses and spins. Isolated binary evolution probably contributes to the observed gravitational-wave sources.

Astronomers have found a brown dwarf transferring mass onto a small star in an 87-min orbit, showing that substellar objects can be gradually consumed over potentially billions of years, rather than swallowed whole.

Niobium has been detected in the atmosphere of a young white dwarf, probably originating from a second-generation planet candidate being evaporated by the white dwarf. The planet probably formed from material ejected during the white dwarf progenitor’s death throes.

The formation process of polycyclic aromatic hydrocarbons (PAHs) at very low metallicity is uncertain. The detection of PAHs in a 7% solar metallicity galaxy, along with emission from compact clumps and small grain sizes, helps elucidate the mechanisms at play.

In Chile, the Center for Astrophysics and Associated Technologies has been working towards turning scientific investment into economic success for two decades, through the transfer of technology and techniques from astrophysics to industry. Many successful projects provide tangible examples of the real-world benefits of astronomy.

The discovery of little red dots with JWST has prompted manifold investigations into their observational properties and physical nature. This Focus issue consolidates our knowledge of these distant objects at a time when firm conclusions are beginning to be drawn.

Heliobiology is a new interdisciplinary field that links heliophysics, astrophysics, planetary science and chemistry with an astrobiological focus. We propose a formal definition of heliobiology and a practical framework for its implementation.

Images reveal where planetary surfaces change, whereas seismic and ground-motion records can show when and why. Treating seismometers as environmental sensors, alongside cameras, meteorological packages and orbital repeat imaging, would make active surfaces a central target of future missions.