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Transiting Exoplanet Survey Satellite data of the massive star HD 192575 reveal pulsation frequencies that allow the inference of its convective core mass and interior rotation profile, thus providing a calibration point for interior chemical and angular momentum transport mechanisms.

This Article reports the detection of oscillations in the massive star β Crucis using polarized light. Such oscillatory modes provide information about stellar structure; in this case the stellar mass, inclination of the rotation axis and size of the convective core.

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.

Measuring the oscillations of a star can allow the various mixing processes in its interior to be disentangled, through the signature they leave on period spacings in the gravity mode spectrum. Here numerous gravity modes in a young star of about seven solar masses are reported: the mean period spacing enables the extent of the convective core to be determined, and the clear periodic deviation from the mean constrains the location of the chemical transition zone — at about 10 per cent of the radius.

Kepler space telescope observations of 26 intermediate-mass rotating stars (slowly pulsating B-type stars) are analysed to isolate the gravity modes that probe the stars’ deep interiors. Internal mixing levels are unexpectedly varied and best reproduced with models incorporating radially stratified mixing profiles.

Leveraging the precision of K2 and TESS, Bowman et al. have detected variability in galactic and Magellanic blue supergiants that is due to low-frequency gravity waves in their interiors.