Which observatory/satellite was launched into space first, Hakucho or Chandra X-ray Observatory?
Hakucho Hakucho (also known as CORSA-b before launch) was Japan's first X-ray astronomy satellite, developed by the Institute of Space and Aeronautical Science (then a division of the University of Tokyo). It was launched by the ISAS M-3C-4 rocket on February 21, 1979 and reentered the atmosphere on April 16, 1985 .
EROSITA eROSITA is an X-ray telescope built by the Max Planck Institute for Extraterrestrial Physics (MPE) in Germany for launch by Roscosmos of Russia, effectively replacing the ROSAT telescope when it reaches its orbit after launch in 2018 on board the Spectrum-Roentgen-Gamma (Spektr-RG / SRG), which also carries the Russian telescope "ART-XC".