(Extended Roentgen Survey with an Imaging Telescope Array)
(Russian/German space X-ray telescope launched in 2019)
eROSITA
(for Extended Roentgen Survey with an Imaging Telescope Array)
is a German space X-rayWolter telescope which is one of the
instruments on the Russian Spektr-RG (SRG) space observatory.
Its primary function is an all-sky astronomical survey
called eRASS (for eROSITA all-sky survey)
covering up to 10 keV (photon energy),
aiming to observe the effects of dark energy.
It began operation in 2019 with the launch of SRG, but in
early 2022 with advent of the Ukraine war, German/Russian
cooperation ceased and eROSITA is presumed shut down.