The “extended ROentgen Survey with an Imaging Telescope Array” (eROSITA) is the next generation of imaging X-ray telescopes. It was launched onboard the  “Spektrum-Röntgen-Gamma” (SRG) satellite on 13th July, 2019 from Baikonur, Kazakhstan (Figure 1).

It reached its designated orbit around the Lagrange point 2 (L2) in October 2019 and after initial calibration and performance verification tests, started its primary mission: to map the hot and energetic X-ray universe in the energy range 0.2-10.0 keV.

Figure 1: Launch of eROSITA. Credit: Roscosmos.

Building upon the telescope design of XMM-Newton and ABRIXAS, eROSITA hosts seven nearly identical X-ray telescopes (Figure 2). With its large field of view of 1° and outstanding spectral resolution, eROSITA is able to observe the entire sky every six months. With a spatial resolution of < 10″, eROSITA is able to resolve even small scale structures.

Figure 2: The seven individual X-ray telescopes of eROSITA. Credit: MPE

The first all-sky survey was completed on 11th June 2020 (Figure 3) and beautifully shows the complexity of the soft X-ray universe. The all-sky map shows us the variety of X-ray sources: From large scale diffuse structures and supernova remnants to compact sources and distant galaxies, with eROSITA we are able to observe a plethora of different objects. The eRO-STEP research group consists of members out of five eROSITA-collaboration core instituts. Therefore, we are able to exploit the full capabilities of eROSITA for a variety of different research topics.

Figure 3: Multi-color composite of the first all-sky survey of eROSITA. Credit: Jeremy Sanders, Hermann Brunner and the eSASS team (MPE); Eugene Churazov, Marat Gilfanov (on behalf of IKI)

For more information on eROSITA, please visit the official website.