A long-term stay on the Moon would subject the human body to a high level of radiation, as radiation in space is generally many times stronger than it is on Earth. Before humans return to the Moon, the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) will send a small measuring device, the M-42 radiation detector, to Lacus Mortis to record radiation levels on the surface. It will travel there on board the commercial Peregrine Mission 1, which is scheduled to launch in late 2021.
M-42 weighs just 250 grams and is around 20 centimetres long. It will transmit radiation readings to Earth during its flight to the Moon and from the lunar surface. "Up until now, we have had relatively few readings associated with the Moon," says Thomas Berger from the DLR Institute of Aerospace Medicine in Cologne. "We are very proud to be part of this mission and to be able to use the data collected during the flight and on the Moon itself to provide valuable knowledge about galactic cosmic radiation." M-42 was developed and built at the Institute, and the data it acquires will also be analysed there. Peregrine Mission 1 is the first commercial lunar lander mission conducted by US space company Astrobotic. DLR was able to secure a place in the payload of the newly developed lander.
Helga and Zohar investigate radiation exposure for future long-term missions
M-42 is identical to the 16 radiation detectors integrated into the phantoms Helga and Zohar. These two mannequins will orbit the Moon and return to Earth on NASA's highly anticipated Artemis-I mission. Helga and Zohar each consist of 38 layers, with thousands of embedded sensors. They represent two female astronauts travelling to the Moon in the cabin of the Orion capsule. Zohar will be wearing a special protective vest during the flight, while Helga will sit in the spaceship without any protection. "This will allow us to measure the radiation levels to which astronauts of both sexes are exposed on a crewed flight to the Moon," says Berger. Such findings will also prove important in preparations for other long-term missions, including those to Mars.
The Peregrine lander's arrival at the 'Lake of Death'
The lunar lander carrying the M-42 radiation detector is planned to touch down in the north-eastern region of the near side of the Moon. DLR is also involved in the radiation measurements conducted on the far side of the Moon since January 2019 by the Chinese Chang'e-4 lunar landing probe.
In addition to DLR, other space institutions and companies are participating in Peregrine Mission 1. Due to the restrictions imposed by the COVID-19 pandemic, the radiation detector is now being shipped to the USA, where it will be attached to the side flap of the lander by the team at Astrobotic. After its arrival in Lacus Mortis ('Lake of Death'), this flap will open, directly exposing the M-42 to cosmic radiation just above the lunar surface. Ultimately, the DLR team envisages conducting measurements across three different scenarios: during the flight, inside the lander on the Moon, and outside on the surface.