Reviews & Analysis

Radial velocity observations of a binary star system have led to the discovery of a gas-giant circumbinary planet, BEBOP-1 c, which is 65 times more massive than Earth, with an orbital period of 215.5 days. The binary system also hosts a smaller, inner transiting planet, TOI-1338 b, making this system a rare multi-planet circumbinary system.

The quantization of spacetime could be revealed indirectly through its imprint on the propagation of particles. An analysis combining data from the IceCube Neutrino Observatory and the Fermi Gamma-ray Space Telescope shows preliminary statistical evidence of such a quantum-spacetime effect.

As pairs of black holes inspiral and merge, they create gravitational waves. These waves hold information about the environment in which the black holes are embedded: using future space-based gravitational-wave detectors, it will be possible to distinguish what kind of environment that is.

A brief but bright flash of optical radiation has been captured only 30 seconds after the onset of a gamma-ray burst. Produced in the interior of the shocked relativistic jet that powered the burst, the optical flash reveals the jet to be narrow and magnetized.

The first maps of the magnetic field in the nebula surrounding the Crab pulsar have been drawn using X-ray polarimetry. They provide insight into the flow of relativistic particles through the nebula and the generation of turbulence.

A laboratory experiment has replicated the braided strands of solar coronal loops and shown that the bursting of individual strands produces X-rays. Measurements of these braided strands and the generated X-rays reveal a multi-scale process that could be responsible for the energetic particles and X-rays that accompany solar flares.

A probabilistic machine learning-based framework for recognizing and predicting microbial landscape patterns at nested spatial scales was developed. The approach substantially increased the probability of detecting biosignatures when tested at a Martian analogue in the high Andes. This search tool has applications for detecting biosignatures on terrestrial or icy planets.

Near-infrared observations of large dark asteroids in the main belt reveal that they have spectral characteristics similar to those of the dwarf planet Ceres. Thermal evolution models suggest that these asteroids accreted at large orbital distances and may have been implanted into the main belt by the dynamic instability of the giant planets.

A device combining a pulsed laser system with an Orbitrap mass analyser is well-suited for in situ exploration of prime astrobiological targets, such as Enceladus. Here a prototype of this instrument that is optimized for spaceflight applications demonstrates that this device could be used to characterize chemical biosignatures in future missions.

The habitability of early Mars’s subsurface to methanogenic microorganisms was assessed using a planetary ecosystem model that couples a subsurface biosphere to the atmospheric chemistry and climate. Mars’s subsurface was initially likely habitable, but the biosphere would have cooled the planet down, potentially compromising its long-term habitability.

A non-accreting and non-beaming neutron star in a close binary is discovered and characterized by modelling the observed periodic variabilities in the visible companion star. This neutron star belongs to an abundant but less-explored population that cannot be seen with popular techniques such as X-ray and gamma-ray observations.

The limits of our knowledge on light–matter interactions (that is, opacity models) will affect the exploration of exoplanetary atmospheres. Accounting for these limits will prevent biased claims. Guided improvements in opacity models, their standardization and dissemination will ensure maximum return on investment from the next-generation observatories, including the JWST.

Surface-energy effects, such as the Kelvin effect, that regulate the formation of ice determine the observed abundance, distribution and evolution of CO in protoplanetary disks.

Observations have mapped the distribution of gas velocities in a circumstellar disk wind for the first time. The high spatial resolution required for these observations is achieved by measuring the maser emission of water molecules. These findings validate theoretical predictions from the 1980s and can be replicated by modern numerical models.

The internal and external pressure of interstellar medium clouds were measured by modelling of Atacama Large Millimeter Array and Very Large Telescope data. Pressure gradients indicated that both cloud collapse and expansion are possible in jet-driven outflows from black holes, potentially altering the star formation rate of their galaxies.

Ultraviolet-detected Fermi bubble clouds have metallicities that are consistent with the clouds having two origins: the Milky Way disk and halo. This result adds complexity to the previously accepted picture that these clouds could only be launched from the disk of the Milky Way into the bubbles.

Although the Earth is depleted in volatile components relative to its potential chondritic precursors, the isotopic compositions of these elements are similar in Earth and chondrites. A theory to explain these observations suggests that rocky material that formed at various temperatures, locations and times in the protoplanetary disk collected to make Earth.

Super-Earths that retain their primordial atmospheres can have long-lasting temperate surfaces. If a layer of water can form on such a planet, it could be liquid for billions of years.

It is unclear what energy sources were responsible for the reionization of hydrogen atoms in the intergalactic medium 13 billion years ago. Measuring the upper limit on the number of ionizing photons produced by quasars has revealed that the contribution of quasars to reionization is negligible, suggesting that galaxies are the major energy sources.

Many interplanetary dust particles collected in Earth’s stratosphere spent millions of years exposed to solar radiation during their journey from sources beyond Neptune, namely the distant Kuiper belt. These Kuiper belt particles are a previously unrecognized population contributing to the zodiacal cloud and to the mass of dust accreted annually by Earth.