In a few years, a small radiotelescope on the dark side of the Moon could help scientists explore the Universe’s past. The instrument, called the Lunar Surface Electromagnetics Experiment-Night (LuSEE-Night), is being developed by Brookhaven and Lawrence Berkeley National Laboratories, the Space Science Laboratory at the University of California, and NASA.
The launch of LuSEE-Night is currently scheduled on a private lunar robotic lander at the end of 2025. After it lands on the far side of our satellite, it will attempt to collect unique measurements.
The Cosmic Middle Ages
The cosmic middle ages refer to a period in the early universe, between about 400,000 and 400 million years after the Big Bang, before stars and galaxies began to form fully. From the far side of the Moon, LuSEE-Night will use onboard antennas, radio receivers, and a spectrometer to measure the faint radio waves of this cosmic period, searching for what scientists call the Cosmic Middle Ages signal.
“So far, we can only make predictions about earlier stages of the universe using a benchmark called the cosmic microwave background signal. The Cosmic Middle Ages signal would provide a new benchmark” said physicist Anze Slosar in a statement. “And if the predictions based on each benchmark don’t match, it means we’ve discovered new physics”.
LuSEE-Night radiotelescope shouldn’t necessarily make such big breakthroughs on its own. The explorer is designed to pave the way for more ambitious instruments in the near future. Larger project could shed light on cosmic issues as large as the nature of dark energy and the creation of the universe.
The Engineering Challenge
Dark side of the Moon is an excellent place to search for weak signals that could contain such clues because it offers something Earth cannot. The constant radio bombardment through our planet creates an environment too noisy for the very sensitive instruments that LuSEE-Night will use. But on the other hand, the landing site also presents enormous challenges.
Surviving the instruments of a radiotelescope on the dark side of the Moon requires a real engineering feat. Temperatures on the far side of our satellite range from about 121 to -173 degrees Celsius. So LuSEE-Night will have to be designed to withstand two weeks of exposure to the Sun while remaining powered for two weeks of darkness. For a two-year mission duration.
“In addition to the significant science return potential, the demonstration of LuSEE-Night’s lunar night survival technology is critical to performing long-duration and high-priority scientific investigations from the lunar surface” said Joel Kearns, vice associate administrator for NASA’s exploration.