The U.S. Department of Energy (DOE) and the National Aeronautics and Space Administration (NASA) are working together to develop a science instrument that will survive the harsh and unforgiving environment of the nighttime lunar surface on the far side of the Moon to attempt first-of-its-kind measurements of the so-called Dark Ages of the Universe.
The instrument is named the Lunar Surface Electromagnetics Experiment – Night (LuSEE-Night), a collaboration between DOE’s Brookhaven and Lawrence Berkeley National Laboratories, UC Berkeley’s Space Science Laboratory, and NASA’s Science Mission Directorate. LuSEE-Night is a pathfinder to understand the Moon’s radio environment to potentially look at a previously unobserved era in our cosmic history.
The Dark Ages are a time in our early universe that occurred between approximately 380,000 and 400 million years after the origin of the universe, known as the Big Bang. The Dark Ages were well before the formation of the stars and galaxies that we see today. Radio wave signals from this period are impossible to measure from Earth due to our planet’s constant “radio pollution” across nearly the entire electromagnetic spectrum. However, our Moon lacks an interfering atmosphere and ionosphere, and the far side of the Moon is continually shielded from harmful radio emissions from the Earth, as well as from the Sun during the lunar night. The far side of the Moon offers a unique environment that allows for observations of sensitive radio astronomy signals that cannot be obtained anywhere else in the near-Earth space environment.
LuSEE-Night, which will be delivered to the far side of the Moon on a future Commercial Lunar Payload Services (CLPS) flight, will utilize deployable antennas and radio receivers to measure these sensitive radio waves from the Dark Ages for the first time. By physically being on the lunar surface and taking measurements at the right time, several external sources of radio interference will be removed, including radio noise from the Sun, Earth, Jupiter, and Saturn. DOE scientists are excited about doing science from the far side of the Moon because it offers a unique environment that is advantageous to not only radio astronomy, but also for possible future gravitational wave observatories and other optical and infrared instrumentation.
“LuSEE-Night is a fascinating experiment that will allow us to observe something we’ve never been able to before - the Dark Ages signal,” said Asmeret Asefaw Berhe, Director of the Office of Science at DOE. “With this collaboration, DOE and NASA are setting conditions for successful exploration of the Dark Ages cosmology in the decades to come.”
However, a significant challenge will be for the instrument to survive the harsh, cold, and dark environment of the lunar night on the far side of the Moon long enough to collect and return data to Earth. Throughout the day and night cycle on the Moon, temperatures swing between around 250°F (120°C) during the day and -280°F (-173°C) at night. This temperature range presents a significant challenge to not only taking and transmitting the data, but also in keeping the instrument from freezing and ending the mission prematurely.
“LuSEE-Night will operate during the cold temperatures of the 14-day lunar night, when no sunlight is available to generate power or heat,” said Joel Kearns, Deputy Associate Administrator for Exploration in NASA’s Science Mission Directorate. “In addition to the significant potential science return, demonstration of the LuSEE-Night lunar night survival technology is critical to performing long-term, high-priority science investigations from the lunar surface.”
If successful, LuSEE-Night could help inform larger future instruments to further measure these otherwise undetectable radio frequencies and help scientists better understand the earliest period of the Universe’s formation and evolution.
"This measurement is very challenging—radio emission from the galaxy is very bright, and our Dark Ages signal is hiding behind it,” said Stuart D. Bale, NASA’s Principal Investigator for LuSEE-Night and a professor at the University of California-Berkeley.
Anže Slosar, the DOE Science Lead and Collaboration Spokesperson added, "Every time we have opened a new frequency window in cosmology, we have unlocked new discoveries about the history of the Universe and our place within it."
Sven Herrmann, the instrument construction Project Manager for DOE and a research scientist at Brookhaven Laboratory and the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC) said, "While I have been working on space missions my entire life, I am very excited about being able to do this for the first time for the Department of Energy."
Brookhaven National Laboratory leads the construction of the instrument for DOE, the science collaboration, and is responsible for the development of the radio receiver, crucial analog and digital electronics, as well as power systems. Lawrence Berkeley National Laboratory is a collaborating institution and is responsible for the development of actuated antenna subsystem hardware and pre-flight antenna characterization.
Brookhaven National Laboratory and Lawrence Berkeley National Laboratory are supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, please visit www.energy.gov/science.