The red sphere in a suit is the Matroshka-R experiment designed for dosimetry measurements onboard the ISS

The spherical phantom is made of tissue-equivalent substance (judging by a colour it’s a meat equivalent). It contains a number of dosimeters which are placed at different depths, that corresponds to different tissues, e.g. 3mm depth corresponds to a crystalline lens, and 70mm - a central nervous system.

Done