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Decadal- to centennial-scale variability has been identified in the Arctic Oscillation, but less is known about variations on the millennial scale. A record of sea-ice drift from off the Alaskan coast shows a 1,500-year cycle in the phase of the Arctic Oscillation.

Observations of the Phoenix cluster using the James Webb Space Telescope reveal rapid cooling in galaxy cluster cores, driven by black hole jets, with gas temperatures mapped between 10⁵ K and 10⁶ K and cooling rates of 5,000–23,000 M_⊙ yr⁻¹.

The impact of the DART spacecraft on the asteroid Dimorphos is reported and reconstructed, demonstrating that kinetic impactor technology is a viable technique to potentially defend Earth from asteroids.

Combining ecophysiological growth models of >135,000 vascular plant species and information on plant growth form, the authors show that 33–68% of the global land surface will experience a significant change in the next 50 years in how climate supports the plant growth forms that define terrestrial ecosystems.

Decoupling emission reduction target determination, air pollution modelling, and health benefit estimation complicates control strategy design. Here an integrated approach identifies strategies to reduce health damages of air pollution, showing that benefits can be achieved cost-effectively by electrifying sources with high primary PM_2.5 emission intensities.

Complex life forms began to emerge during the Precambrian. Here, the authors tie this evolution to an increase in trace metal availability, namely the Mo content of lacustrine shales, suggesting that life evolved in terrestrial and marginal marine environments rather than the Mo-limited deep ocean.

Assumptions about the use of biomass and CO₂ sequestration drive key differences in how emissions from remaining fuels are mitigated in net-zero energy systems, with potentially significant tradeoffs that will need to be evaluated and managed.

Singlet fission produces two low-energy triplet excitons that are difficult to dissociate into free charges. Now, separate optima in charge yield have been observed as a function of driving force for singlet and triplet excitons in pentacene. At optimal driving forces, the triplet-exciton dissociation rate is at least five orders of magnitude smaller than the singlet-exciton dissociation rate.

An extensive survey to search for members of the only known Kuiper belt family, named after the parent body Haumea, found no family members fainter than absolute magnitude H_r = 7.9, significantly brighter than the detection limit (H_r = 9.5). This lack of small members is inconsistent with a catastrophic disruption as the origin of the Haumea family.

Strong near-infrared spectral features from asymptotic giant branch stars are detected by JWST in the integrated light from distant quiescent galaxies, clarifying their contribution to galaxy spectra and population synthesis models.

The Carnot efficiency and the power output of thermoelectric power generation increase with temperature but current thermoelectrics are characterized up to 1,500 K. Here, Li et al. develop reduced graphene oxide films that can convert heat up to 3,000 K with high power factors, opening the door for novel applications.

Despite global initiatives to reach net-zero CO2 emissions, the tradeoffs of energy systems to reach that goal remain understudied. Here the authors analyze all net-zero scenarios used for the 2018 IPCC report and quantify the role of renewable energy, fuels, and emissions in attaining a zero CO2 world.

An individual star at z = 1.49 is gravitationally lensed and highly magnified by a foreground galaxy cluster. Fluctuations in the star’s emission provide insight on the mass function of intracluster stars, compact objects and the presence of dark-matter subhaloes.

The accretion geometry of X-ray binary Cygnus X-3 is determined here from IXPE observations. X-ray polarization reveals a narrow funnel with reflecting walls, which focuses emission, making Cyg X-3 appear as an ultraluminous X-ray source.

Hybrid metal halide semiconductors typically rely on chiral A-site ammonium cations for chiral induction in the lattice. Now it has been shown that chirality in low-dimensional achiral metal halide semiconductors can be induced by non-ammonium, non-A-site chiral molecules through remote stereocontrol of the inorganic framework.

Fine silicate dust generated by the Chicxulub impact had a dominant role in the global cooling and disruption of photosynthesis that followed, according to palaeoclimate simulations constrained by grain-size analysis of Cretaceous-Palaeogene boundary sediments.

Siew et al. using multi-omic, physiological & imaging approaches have demonstrated that spaceflight causes kidney remodelling, suggesting a contribution to kidney stone formation, & that space radiation causes kidney damage & early signs of dysfunction.

Robust estimates of either urban expansion worldwide or the effects of such phenomenon on terrestrial net primary productivity (NPP) are lacking. Here the authors used the new dataset of global land use to show that the global urban areas expanded largely between 2000 and 2010, which in turn reduced terrestrial NPP globally.

The architecture of planetary systems is shown to be strongly affected by stellar clustering in position-velocity phase space; hot Jupiters occur preferentially at high density, suggesting that their extreme orbits originate from environmental perturbations.

Vandenberg et al. identify differing roles of yeast DNA polymerases during accurate and mutagenic synthesis past common and rare ultraviolet light photoproducts. Similar mechanisms may contribute to driver mutations causing skin cancer in humans.

Fe isotopic composition of the distal ejecta of a terrestrial impact crater records both evaporation and condensation, refining the nature of the isotopic fractionation taking place during hypervelocity impacts in the Solar System.

Most of the meteorites on the Earth’s surface are found in Antarctica. Here the authors show that ~5,000 meteorites become inaccessible per year as they melt into the ice due to climate change.

Indirect forcing by low regional orography and high atmospheric methane levels contributed to the amplified Arctic temperatures in the early Eocene by enhancing polar stratospheric cloud formation, according to an atmospheric model with interactive chemistry.

Red giants are evolved stars that have exhausted the supply of hydrogen in their cores and instead burn hydrogen in a surrounding shell. Once a red giant is sufficiently evolved, the helium in the core also undergoes fusion. However, it is difficult to distinguish between the two groups. Asteroseismology offers a way forward. This study reports observations of gravity-mode period spacings in red giants using high precision photometry obtained by the Kepler spacecraft. It is found that the stars fall into two clear groups, making it possible to distinguish unambiguously between hydrogen-shell-burning stars and those that are also burning helium.

The high performance of hybrid perovskite solar cells has attracted significant attention but the nature of the underlying mechanisms remains unclear. Frohna et al. show methylammonium lead iodide perovskite is centrosymmetric, invalidating previous predictions of a large bulk Rashba effect.

Climate variability in the Southern Hemisphere is dominanted by the Southern Annular Mode, which influences temperatures and latitudinal rainfall distribution. This work reconstructs its annual variability since the year 1000. The authors find that a positive trend since the 1940s is reproduced by climate model simulations with representative greenhouse gas forcings and ozone depletion. Early trends indicate a teleconnection to tropical Pacific climate, which may need to be considered in projections under climate change.

Applying mass–radius–composition models to the exoplanet system of the M dwarf star TRAPPIST-1, its planets f and g are determined to contain substantial amounts of water, whereas b and c are much drier.

Silicon-vacancy (SiV) centers in diamond are emerging as promising quantum emitters for various applications. Here, authors devised a novel pulsed annealing scheme that improves the conversion efficiency of SiV centers in diamond.

Singlet fission in organic semiconductors can generate triplet exciton pairs that are crucial to the charge generation in a photovoltaic process, whilst their nature remains elusive. Here, Yonget al. show that the immediate triplet pair is bound and emissive in a range of acene and heteroacene materials.

The habitability of a planet is defined at a fixed time. A bigger challenge is to understand how that habitability is sustained over geological timescales, and how the underlying processes compare across different planetary bodies.

Low-mass, low-metallicity cool subdwarf stars are rare in the solar neighbourhood, and therefore their properties are not well constrained observationally. Here the authors report both a mass and radius determination of a cool subdwarf in an eclipsing binary system, providing a valuable data point.

The snow-line is the distance from a protostar at which a particular volatile gas condenses; images of the protostar V883 Ori suggest that the water snow-line migrated outwards during a protostellar outburst, with implications for our understanding of the formation of planetary systems such as our own.

Stellar data from the Kepler spacecraft are used to infer the existence of a sub-Mercury-sized exoplanet, the smallest yet discovered, in orbit around a Sun-like star.

A study reports the measurement of the polarization degree and angle of X-rays from Sagittarius A^* reflected off a nearby cloud, indicating an X-ray flare about 200 years ago.

The influence of the thermodynamic driving force for photoinduced electron-transfer between single-walled carbon nanotubes and fullerene derivatives has been investigated. The Marcus inverted region and small reorganization energies were observed for this model organic heterojunction. Small reorganization energies aid in minimizing energy losses for solar conversion to electricity or fuels.