Specialists from Russia's space agency are attempting to fix issues that have blocked control of the country's only orbiting radio telescope, Spektr-R.
Astro Space Centre chief Nikolai Kardashev said Spektr-R is still transmitting scientific data but it has not responded to commands from earth since Friday, according to the RIA Novosti news agency.
The telescope was launched in 2011 from the Baikonur Cosmodrome in Kazakhstan with the primary goal to preform research on the structure and dynamics of radio sources within and beyond our Milky Way galaxy.
Spektr-R has been operational far beyond its expected five-year lifespan.
An official from Russian space agency Roscosmos, Alexander Bloshenko, said Saturday that another attempt to establish control of the satellite will take place on Sunday.
Spektr-R also referred to as the RadioAstron project, is led by the Astro Space Center (ASC) of the Lebedev Physical Institute of the Russian Academy of Sciences in Moscow.
Spektr-R became the first Russian astrophysics spacecraft to go into orbit in the 21st century, carrying a 10 metre radio telescope on board. The heart of the telescope also carries 27 carbon fiber petals.
In 2002, the Russian Academy of Sciences gave Spektr-R the highest priority among the nation's astrophysics missions, however it did not reach the launch pad until 2011.
The orbit of the RadioAstron satellite evolves with time and has an apogee height between 270,000 and 370,000 km, a perigee between 7,000 and 80,000 km, a period of 8 to 9 days, and an initial inclination of 51 degrees.