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M-42 radiation detector

Peregrine Mission One · failed to land · commercial payload

A small silicon radiation detector (250 g, about 20 cm) mounted on a side panel of the lander. It records energy-deposition spectra of charged particles to give the radiation dose in transit and, after landing, just above the lunar surface, for astronaut radiation protection.

PI: Thomas Berger (DLR), project manager
Built by: German Aerospace Center (DLR), Institute of Aerospace Medicine, Cologne (partner agency)
Technology radiation monitor (silicon detector)
Moon Base need DN-012 L (The study's reading, and partial, as for LETS. DN-012 L asks for long-term South Pole radiation measurements including neutrons up to 100 MeV; M-42 measures charged-particle energy deposition up to about 20 MeV in silicon, and Peregrine aimed at a mid-latitude site. DLR says the aim is radiation knowledge for future astronaut missions.)
Route onto CLPS commercial; DLR bought a place on Peregrine from Astrobotic, outside NASA's task order; NASA's press kit counts 15 payloads from other customers. DLR announced it in April 2021, when the launch was planned for late 2021 and the landing site was Lacus Mortis.; 2021-04-22
Timeline first funding not in public sources; first flight test not in the saved sources (earlier M-42 flights on a balloon, a sounding rocket and the ISS are undated there); selected by April 2021 (DLR announcement); launch 2024-01-08; landing not in public sources
On the Moon partly operated
FO none

Flights before the Moon

  • sounding rocket or balloon (not FO): MARSBOx / E-MIST stratospheric balloon experiment, 36 km (NASA-DLR), with an M-42, not in the saved slides (cited paper Berger et al. 2021). An M-42 detector in the stratosphere. DLR lists it among the M-42's earlier radiation measurements. Not an FO flight in FO's records.

"MARSBOx / E-MIST (DLR M-42)"
— Astrobotic Peregrine 1 Mission: DLR M-42 data; update on M-42 instrument family (DLR M-42 Team, W…, slide 2 (DLR, WRMISS 27, Sept 2024)

  • ISS or MISSE: RadMap on the International Space Station (420 km), with an M-42, not in the saved slides (cited paper Losekamm et al. 2023). An M-42 detector in low Earth orbit.

"RadMap (DLR M-42)"
— Astrobotic Peregrine 1 Mission: DLR M-42 data; update on M-42 instrument family (DLR M-42 Team, W…, slide 2

"MAPHEUS (DLR M-42)"
— Astrobotic Peregrine 1 Mission: DLR M-42 data; update on M-42 instrument family (DLR M-42 Team, W…, slide 2

  • Earth orbit or deep space: NASA's Artemis I (Orion), in DLR's MARE phantoms Helga and Zohar, 2022-11-16 (Artemis I launch). Sixteen detectors identical to the Peregrine M-42 flew around the Moon and back inside the two phantoms, a year before Peregrine.

"M-42 is identical to the 16 radiation detectors integrated into the [phantoms Helga and Zohar]"
— DLR – M-42 will measure radiation on the MoonVisit us on InstagramVisit us on LinkedinVisit us on…

"MARE (DLR M-42)"
— Astrobotic Peregrine 1 Mission: DLR M-42 data; update on M-42 instrument family (DLR M-42 Team, W…, slide 2 ('To the Moon and back')

"Launch and Deployment: November 16, 2022"
— NTRS 20230011375, slide 6 (BioSentinel, launched on Artemis I)

  • aircraft (not FO): Airline flights (long-haul, Europe to Japan and the USA), before July 2019 (paper submitted 30 July 2019). M-42 detector versions measuring the aviation radiation field, the first use of the M-42 electronics in a mixed radiation field; DLR counts airplane flights among the family's applications.

"M-42 systems were already applied for measurements in airplanes, during two MAPHEUS (Materialphysikalische Experimente unter Schwerelosigkeit) rocket missions"
— elib.dlr.de: ME-SBA-2019-Berger%20et%20al%20M-42%20MAPHEUSRev.%20Sci.%20Instrum.%2090%20125115.pdf, abstract

"data have been collected for long haul flights from Europe to Japan and the USA applying various versions of the M-42 system"
— elib.dlr.de: ME-SBA-2019-Berger%20et%20al%20M-42%20MAPHEUSRev.%20Sci.%20Instrum.%2090%20125115.pdf, section IV A, Airplane flights

"successfully applied on several airplane flights, NASA balloon flights over Antarctica, MAPHEUS (sounding rocket) flights"
— Update on the DLR M-42 instrument family and future missions (Kasemann et al., 28th WRMISS, Colog…, abstract (DLR, WRMISS 2025)

Heritage hardware

  • design heritage (M-42 family): M-42 is one of a DLR family of small silicon detectors (Compact, Split, Display, EXTended, BIG). The Peregrine flight model has a 1.22 square cm, 300 micron silicon sensor. DLR is developing further versions of the family.

"DLR M-42 Detector Family"
— Astrobotic Peregrine 1 Mission: DLR M-42 data; update on M-42 instrument family (DLR M-42 Team, W…, slides 3-11

"DLR M-42 Astrobotic FM"
— Astrobotic Peregrine 1 Mission: DLR M-42 data; update on M-42 instrument family (DLR M-42 Team, W…, slide 14 (technical data: silicon detector, 1.22 cm2, 300 µm)

"new instruments from the M-42 detector family are currently under development"
— M-42 radiation detector flies to the MoonVisit us on InstagramVisit us on LinkedinVisit us on You…

Funding before the lunar flight

  • DLR (German Aerospace Center) internal funding. No amount in public sources; no US federal funding found. (DLR; not in public sources): amount not in public sources

"M-42 was developed and built at the Institute"
— DLR – M-42 will measure radiation on the MoonVisit us on InstagramVisit us on LinkedinVisit us on…

How it got onto CLPS

"DLR's M-42 radiation detector will travel to the Moon on board Peregrine Mission 1."
— DLR – M-42 will measure radiation on the MoonVisit us on InstagramVisit us on LinkedinVisit us on…

"DLR already secured a"
— M-42 radiation detector flies to the MoonVisit us on InstagramVisit us on LinkedinVisit us on You…, 'place on the Peregrine lander two and a half years ago'

"Peregrine will also carry 15 payloads from other customers, unrelated to NASA"
— NASA press kit, Commercial Lunar Payload Services Initiative: Astrobotic's Peregrine Mission One…

On the Moon

Peregrine could not land. M-42 was powered on shortly after separation and sent data to DLR throughout the mission, through the radiation belts and in free space. Astrobotic counts it among the three payloads (with LETS and NSS) that collected publishable scientific data. DLR presented preliminary results in September 2024; those slides mark the data preliminary and confidential, so no values are quoted here. No lunar surface data.

"DLR's M-42 radiation detector collected data during the mission and sent it to DLR."
— M-42 radiation detector flies to the MoonVisit us on InstagramVisit us on LinkedinVisit us on You…, update of 22 Jan 2024

"The M-42 radiation detector is currently transmitting data as planned, which is being received at DLR."
— M-42 radiation detector flies to the MoonVisit us on InstagramVisit us on LinkedinVisit us on You…, update of 10 Jan 2024

"NOTE: All data preliminary and confidental"
— Astrobotic Peregrine 1 Mission: DLR M-42 data; update on M-42 instrument family (DLR M-42 Team, W…, slide 1

"Two NASA payloads, Linear Energy Transfer Spectrometer (LETS) and Neutron Spectrometer System (NSS), and one commercial payload, The German Aerospace Center (DLR)'s M-42 Radiation Detector, collected publishable scientific data."
— Peregrine: Mission 1, August 2024 Post-Mission Report (Astrobotic), p. 17, (Astrobotic post-mission report, Aug 2024)

FO's role

Grade: none. No FO project, flight or report names M-42, DLR or MARSBOx (searched FO's 430 TechPort records, its reports and its pages). M-42's earlier flights were on a NASA-DLR balloon experiment, a DLR sounding rocket, the ISS and Artemis I, none of them FO. FO did fly other radiation monitors (ARMAS): same topic only.

Who built it

"M-42 was developed and built at the Institute, and the data it acquires will also be analysed there."
— DLR – M-42 will measure radiation on the MoonVisit us on InstagramVisit us on LinkedinVisit us on…, DLR, 22 Apr 2021

"says Project Manager Thomas Berger from the DLR Institute of Aerospace Medicine"
— M-42 radiation detector flies to the MoonVisit us on InstagramVisit us on LinkedinVisit us on You…, DLR, Jan 2024

Moon Base need

"Measure the radiation environment on the lunar surface at the south pole."
— Moon to Mars knowledge base: DN-012 L: In situ lunar surface radiation environment measurements and space weather monitoring, Description

"In order to gather further information for future astronaut missions to the Moon and to develop appropriate protective measures"
— M-42 radiation detector flies to the MoonVisit us on InstagramVisit us on LinkedinVisit us on You…

Open questions

  • When did the M-42's balloon (MARSBOx/E-MIST), MAPHEUS rocket and RadMap ISS flights take place, and who flew the balloon? The DLR slides cite papers but give no dates.
  • Has DLR published its Peregrine M-42 results? The September 2024 slides call the data preliminary and confidential.
  • M-42's cost and DLR's price for the Peregrine ride: not in public sources.