MARE – The MATROSHKA AstroRad Radiation Experiment

MARE - The MATROSHKA AstroRad Radiation Experiment

Space radiation is a major health risk for humans and thus a decisive factor for planned long-term human space missions in the future. With the MARE experiment (Matroshka AstroRad Radiation Experiment), DLR and other partners are now making a major contribution to determining this radiation risk and developing protective measures. On the NASA Artemis I mission, the MARE experiment for the first time flew two female phantoms to determine the radiation risk on its way to the Moon. Both phantoms were equipped with radiation detectors and one wore a radiation protection vest. Both are modelled on humans, so that the radiation dose can be measured in the particularly radiation-sensitive organs.

Helga and Zohar, as the two phantoms are called, travelled in the passenger seats on Orion's first flight to the moon as part of the Artemis I mission in December 2022. Zohar wore a newly developed radiation protection waistcoat (AstroRad) from Israeli partner StemRad. The phantoms each consist of 38 discs and flew on behalf of two astronauts. In Cologne at the DLR, the two phantoms were equipped with sensors by the Institute of Aerospace Medicine. This made it possible for the first time to measure with great accuracy the radiation exposure of the astronauts during a manned flight to the moon.

MARE
Built up of the anthropomorphic phantoms (Manufacturer: CIRS, Norfolk, USA www.cirsinc.com)

The 95-centimetre-tall female phantoms are equipped with organs and bones made of plastic of different densities. The radiation detectors that were installed in the Helga and Zohar phantoms were developed, built and tested at DLR. A total of 1400 sensor positions were equipped with small passive radiation detectors consisting of crystals, while the sensors of the active detectors were integrated into the most radiation-sensitive organs of the body - lungs, stomach, uterus and bone marrow. While the passive detectors measured continuously from launch to return to earth and recorded the total exposure, the active, battery-powered detectors were switched on during the launch and recorded the radiation exposure over time. After the return, the various detectors were read out and data on the journey to the moon was analysed.

The data from the Helga phantom, which flew without a protective waistcoat, will also be used to determine the effectiveness of the newly developed radiation protection waistcoat (AstroRad) developed by industrial partner StemRad, which is funded by the Israeli Space Agency (ISA).

International cooperation between numerous universities and research institutions

In its complexity and in its international cooperation with numerous universities and research institutions in Austria, Belgium, Poland, Hungary, the Czech Republic, Greece, Switzerland, Japan and the USA, MARE represents the largest experiment ever to determine the radiation exposure of astronauts beyond low Earth orbit. It provides basic data for estimating the radiation risk for future manned flights to the Moon.

News about MARE

August 13, 2026

AstroRad vest can significantly reduce radiation exposure for humans in space

Humanity is gradually returning to the Moon with NASA's Artemis programme. The first test flight, Artemis I, took place in late 2022. On this mission, the Orion spacecraft launched without a crew, but it was packed with scientific experiments.

September 18, 2024

Orion spacecraft radiation protection tested: initial findings from Artemis I Moon mission

During long-term astronaut missions, space radiation poses health risks to the human body. Such radiation can lead to cancer and several degenerative organ diseases, so suitable protective measures need to be found to ensure that astronauts are protected to the greatest extent possible during ever longer space missions in the future.

March 9, 2023

Artemis I lunar mission: The first of a new gen­er­a­tion of lu­nar 'as­tro­nauts' re­turn to Cologne

Following their historical journey around the Moon as part of NASA's Artemis I mission, the radiation-measuring mannequins, Helga and Zohar, are back in Cologne. On 9 March 2023, the two female astronaut phantoms were presented to the media by the German Aerospace Center at its Institute of Aerospace Medicine for the first time since their flight...

January 18, 2023

Artemis I lunar mission: NASA hands over fe­male 'as­tro­naut' phan­toms safe and sound af­ter flight to the Moon

It was a historic journey. As part of NASA's Artemis I mission, the Orion spacecraft, powered and supplied by the European Service Module (ESM), flew to the Moon and back for the first time. On board were the two female astronaut phantoms, Helga and Zohar – part of the first experiment conducted in space to measure the radiation exposure to which the female body is exposed during such a flight...

December 9, 2022

The first fe­male 'as­tro­nauts' re­turn from the Moon

The return from the Moon is imminent. NASA's Artemis I mission is expected to splash down in the Pacific Ocean off the coast of California this Sunday, 11 December 2022 at 18:40 CET. The journey to the Moon, in lunar orbit and back to Earth lasted more than 25 days and now lies behind the Orion spacecraft, which is powered and supplied by the European Service Module (ESM)...

November 16, 2022

NASA's Artemis I lu­nar mis­sion suc­cess­ful­ly launched

On 16 November 2022, NASA's Artemis I mission blasted off to the Moon from Launch Pad 39B at NASA's Kennedy Space Center in Florida. The new SLS rocket lifted off at 07:47 CET, carrying the Orion spacecraft towards Earth’s natural satellite. The mission is expected to last 26 days...

November 15, 2022

#Lu­naTwins on board Artemis I ready for launch

The return to the Moon is just around the corner. The launch window opens for NASA's Artemis I mission opens this Wednesday, 16 November 2022, at 07:04 (CET). After several postponements, it is now set to go – taking humankind back to the Moon almost exactly 50 years after the last Apollo flight in December 1972...

August 24, 2022

'Green light’ for the return to the Moon

+++ Update as of 29 August 2022, 14:34 CEST: NASA aborted the Artemis I launch attempt at approximately 08:34 local time on Aug. 29. The Space Launch System launch vehicle and Orion spacecraft remain in a safe and stable configuration, according to NASA...

August 10, 2022

'Boarding' for the Artemis I mission – Helga and Zohar are ready for their flight to the Moon

Three mannequins, a beagle and a sheep fly around the Moon in a giant rocket … extraordinary, isn’t it? This special crew is part of NASA’s Artemis I mission, scheduled to launch from Kennedy Space Center in Florida on 29 August 2022...

The MARE cos­mic ra­di­a­tion ex­per­i­ment on board Artemis I

Outside Earth's protective magnetic field, radiation exposure is very high for humans. It poses a considerable health risk for future crews on long-term missions to the Moon and Mars. That is why it is crucial to determine this exposure more precisely and to develop measures to protect astronauts.

Video (german): MARE - Tracking radiation exposure on the way to the Moon
The German Aerospace Center (DLR) is leading the MARE experiment. The main project partners are the Israeli Space Agency (ISA), the Israeli industrial partner StemRad, which developed the AstroRad protective waistcoat, Lockheed Martin and NASA. In its complexity and in its international collaboration with numerous universities and research institutions from Europe, Japan and the USA, MARE represents the largest experiment to determine radiation exposure for astronauts to leave low-Earth orbit. The measurements taken during Artemis I will provide valuable risk assessment and mitigation data for future exploration missions and enable safe human exploration of space.

Video (german): MARE - Tracking radiation exposure on the way to the Moon

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Video (german): MARE - Tracking radiation exposure on the way to the Moon
The German Aerospace Center (DLR) is leading the MARE experiment. The main project partners are the Israeli Space Agency (ISA), the Israeli industrial partner StemRad, which developed the AstroRad protective waistcoat, Lockheed Martin and NASA. In its complexity and in its international collaboration with numerous universities and research institutions from Europe, Japan and the USA, MARE represents the largest experiment to determine radiation exposure for astronauts to leave low-Earth orbit. The measurements taken during Artemis I will provide valuable risk assessment and mitigation data for future exploration missions and enable safe human exploration of space.

Project

MARE

Duration

2016-2026

Other project participants

Israel Space Agency (ISA)/Israel

StemRad/Israel

Lockheed Martin Space (LM)/USA

National Aeronautics and
Space Administration (NASA)/USA

Contact

Dr. techn. Thomas Berger

Head of Radiation Biology
German Aerospace Center
Institute of Aerospace Medicine
Radiation Biology
Linder Höhe, 51147 Cologne