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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.

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 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.

During a photoinduced phase transition, electronic rearrangements are usually faster than lattice ones. Time-resolved measurements now show that the insulator-to-metal transition in a thin-film Mott insulator is preceded by lattice reconfiguration.

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.

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.

Soft X-ray observations of the southern Galactic sky with the HaloSat CubeSat indicate that the circumgalactic medium (CGM) of the Milky Way has a disk-like profile, with an extended spherical halo. Clumps in the CGM correlate with star-formation activity.

Stellar intensity interferometry (SII) is undergoing a revival. Here, data from the four 12 m optical reflectors of the VERITAS array are correlated post facto to determine the angular diameter of two stars to a high precision, laying the groundwork for SII at future large Cherenkov arrays.

Using large-aperture Cherenkov telescopes, Benbow et al. have measured the angular sizes of two stars through timely occultations by asteroids, achieving an order of magnitude improvement in resolution over the lunar occultation method.

Cosmic rays are believed to be mainly accelerated by the winds and supernovae of massive stars, although definite evidence for this is lacking. The active regions of starburst galaxies have exceptionally high rates of star formation, and therefore should produce cosmic rays that interact with interstellar gas and radiation to produce diffuse γ-rays. The detection and analysis of >700-GeV γ-rays from M82, the prototype small starburst galaxy, now links cosmic-ray acceleration to star formation activity.