The space rocket launch was originally planned for 12 June, but was delayed due to problems with the electric current source.
Spektr-RG is a Russian-German project, the main mission of which is to scan the sky in a wide energy range with high sensitivity and angular resolution.
The Proton-M is the largest carrier rocket in Russia's fleet of space launch vehicles. The rocket has lifted dozens of Russian-made and foreign satellites into orbit since it was first commissioned in 2001.
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