NASA better move fast! In February of 2019, China established the first human-technology landing site on Moon’s far side that they named “The Milky Way Base”. China has named the landing site of its Chang’e-4 lunar probe (image landing above) “Statio Tianhe” –after the Chinese name for the Milky Way Galaxy for the first-ever soft landing on the far side of the moon The Chang’e-4 probe, launched on December 8, 2018 landed on the Von Karman Crater in the South Pole-Aitken Basin on January 3. A Dutch-built radio antenna traveled with Chang’e 4 to usher in a new era of radio astronomy allowing for the study of objects that might otherwise be invisible or hidden in other parts of the electromagnetic spectrum.
China’s base on the lunar far side will allow them to detect radio waves below 30 MHz, that are are blocked by Earth’s atmosphere. It is these frequencies in particular that contain information about the early universe, observed Heino Falcke – professor of radio astronomy and astroparticle physics at the Radboud University in the Netherlands and winner of the 2011 Spinoza Prize. In December, 2019, three Dutch-built radio antennas led by Falcke, lead scientist on the project, attached to the Chinese communications satellite, Queqiao, which has been supporting Chang’e 4, were outstretched to capture whispers that may unveil a mysterious period in the universe’s early history.
The moon’s far hemisphere is never directly visible from Earth and while it has been photographed, with the first images appearing in 1959, it has never been explored. A pioneering radio telescope on the moon’s pristine far side, will give it an unobstructed window on the cosmos.
NASA’s incubator program has awarded a grant for research into turning a huge crater on the far side of the Moon into a giant radio telescope –a 1 kilometer -diameter wire-mesh using wall-lclimbing DuAxel robots in a 3-5 -diameter lunar crater, with suitable depth-to-diameter ratio to form a sphericalcap reflector. This Lunar Crater Radio Telescope (LCRT), will be the largest filled-aperture radio telescope in the Solar System! LCRT could enable tremendous scientific discoveries in the field of cosmology by observing the early universe in the 10– 50m wavelength band ( 6–30MHz frequency band).
An ultra-long-wavelength radio telescope on the far-side of the Moon has tremendous advantages compared to Earth-based and Earth-orbiting telescopes . Such a telescope can observe the universe at wavelengths greater than 10m (i.e., frequencies below 30MHz), which are reflected by the Earth’s ionosphere and are hitherto largely unexplored by humans. Second, the Moon acts as a physical shield that isolates the lunar-surface telescope from radio interferences from Earth-based sources, ionosphere, Earth-orbiting satellites, and the hiss of the Sun’s radio-noise during the lunar night.
NASA’s Institute for Advanced Concepts (NIAC) is a platform that each year nurtures visionary ideas that have the potential to create breakthrough technologies for possible future space missions, by funding projects still in the early stages of development. One of the new successful applicants is Saptarshi Bandyopadhyay, a robotics technologist at NASA’s Jet Propulsion Laboratory. Bandyopadhyay’s idea is to turn a suitable existing lunar crater, one to 50 kilometers in diameter, on the far-side of the Moon into a spherical reflecting dish and use it as a radio telescope. Called the Lunar Crater Radio Telescope (LCRT), the dish would be able to observe the Universe in the 5 –100 meter wavelength band, a region of the electromagnetic spectrum rarely utilised in astronomy.
The Daily Galaxy, Sam Cabot, via NASA