Russia’s Millimetron telescope gets a 10-meter mirror that folds to fit a rocket

The Spektr-M space observatory, also known as Millimetron, will be able to deploy a 10-meter reflective surface in orbit. The work is being carried out by Reshetnev Information Satellite Systems, according to Roscosmos.

The mirror has a transformable design: folded, it fits inside a rocket fairing and unfolds after reaching orbit. The telescope will observe in millimeter and infrared wavelengths, from 0.02 to 17 millimeters. The reflector will be cooled to extremely low temperatures to reduce thermal noise and pick up faint signals from deep space. Scientists estimate that the large diameter combined with high surface accuracy will deliver record sensitivity and angular resolution.

The spacecraft will be placed at the L2 Lagrange point, 1.5 million kilometers from Earth, the same location as the James Webb Space Telescope. At this position, the Sun, Earth, and Moon always remain on one side of the station, simplifying thermal protection and ensuring stable observations. The complex will weigh about 6,600 kilograms and will be launched by an Angara rocket from the Vostochny Cosmodrome. The launch was initially planned for 2029, but the timeline has been postponed several times; a realistic estimate now points to the mid-2030s.

The Millimetron project has been in development in Russia for more than a decade. The observatory is expected to study the early universe, black holes, and the formation of stars and galaxies.