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Ground-based observations during a thunderstorm provide conclusive evidence of positrons being produced after lightning, confirming that lightning can trigger photonuclear reactions.

Thunderstorms are thought to produce two types of high-energy emissions, terrestrial gamma-ray flashes and gamma-ray glows however due to the difficulty in their observation the exact relation between the two is still not well-understood. Here, the authors report the simultaneous detection of a gamma-ray glow and a downward terrestrial gamma-ray flash suggesting the origin of the two phenomena are related.

X-ray observations of two large glitches bracketing a fast radio burst in the active Galactic magnetar SGR 1935+2154 reveal a connection between rapid spin change and radiative behaviours of the magnetar.

Observations of a luminous quasar from the high-resolution spectrometer Resolve aboard XRISM revealed highly inhomogeneous wind structure outflowing from a supermassive black hole, which probably consists of up to a million clumps.

IXPE has revealed how the spin of the accreting neutron star Hercules X-1 changes in three dimensions. The spin axis of the star moves both through the star and across the sky, hinting that the crust of the star is asymmetric by almost one part in a million.

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.

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.

X-ray polarization measurements of the Crab nebula and pulsar by the IXPE satellite reveal a global toroidal magnetic field with large variations in local polarization, suggesting a more complex turbulence distribution than anticipated.

X-ray polarimetry observations with the Imaging X-ray Polarimetry Explorer constrain the accretion geometry in an X-ray pulsar and provide evidence for a misalignment of the spin, magnetic and orbital axes in Her X-1.

Polarization can exceed 60% at the leading edge of the inner part of the Vela pulsar wind nebula; in contrast with the case of the supernova remnant, the electrons in the pulsar wind nebula are accelerated with little or no turbulence in a highly uniform magnetic field.

Polarization measurements are reported for the blazar Mk501, revealing a degree of X-ray polarization that is more than twice the optical value and supporting the shock-accelerated energy-stratified electron population scenario.

X-ray spectroscopic observations of the Centaurus galaxy cluster with the X-Ray Imaging and Spectroscopy Mission satellite show that the hot gas flows along the line of sight relative to the central galaxy.

In June 2022, the IXPE satellite observed a shock passing through the jet of active galaxy Markarian 421. The rotation of the X-ray-polarized radiation over a 5-day period revealed that the jet contains a helical magnetic field.

Observations of V404 Cygni, an X-ray transient containing a black hole of nine solar masses and a companion star, show that optical oscillations on timescales of 100 seconds to 2.5 hours can occur at mass-accretion rates at least ten times lower than previously thought, suggesting that the accretion rate is not the critical parameter for inducing inner-disk instabilities.

High-resolution X-ray spectra show near-solar abundances of chromium, manganese and nickel with respect to iron in the Perseus cluster, suggesting that the progenitors of type Ia supernovae could be near- and sub-Chandrasekhar-mass white dwarfs.

X-ray observations of the core of the Perseus cluster reveal a remarkably quiescent atmosphere in which the gas has a line-of-sight velocity dispersion of about 164 kilometres per second in the region 30–60 kiloparsecs from the central nucleus; turbulent pressure support in the gas is four per cent of the thermodynamic pressure, necessitating only a small correction to the total cluster mass determined from hydrostatic equilibrium.