MASCOT ("Mobile Asteroid Surface SCouT") is a surface science platform that was launched on December 3, 2014 with the Hayabusa2 (JAXA) sample return mission. The target of this mission is the near-Earth asteroid (162173) Ryugu. After almost 4 years of flight, MASCOT was separated from the mother ship on October 3, 2018 at 3.58am (CEST) from a height of about 42m above Ryugu's surface. About 20 minutes after the separation the MASCOT lander came to rest on the asteroid and continued its scientific operation for the next 17 hours. Its four scientific instruments (MASCam, MicrOmega, MASMag and MARA) were operated to collect data from several locations on the asteroid's surface.

MASCOT was built under the leadership of the German Aerospace Center (DLR) in close cooperation with the French space agency CNES and the Japanese space agency JAXA.

The total mass of the lander is just ten kilograms including the scientific instruments MASCam (camera) and MARA (radiometer) of the DLR Institute of Planetary Research, as well as a hyperspectral infrared microscope (MicrOmega) of the Institute of Astrophysics Spatiale and the magnetometer (MASMag) of the TU Braunschweig.

The goal of these experiments is to determine the surface structure, mineralogy, surface temperature and magnetic field of the asteroid. All this information, together with the data from the remote sensing instruments on board Hayabusa2 and the later returned asteroid samples, should provide important insights into Ryugu's composition, its formation and development in particular. The Hayabusa2 mission aims to increase our knowledge about the early history of the solar system and its evolutionary processes, and to draw possible conclusions about the origin of water and organic materials on Earth via asteroid impacts.

Why research asteroids?

Asteroids, like comets, are small bodies within the Solar System. They are not only the remains of the earlier stages of planet formation, but are also believed to be where the water on Earth originated: heaving bombardment of the young Earth by asteroids around 3.8 billion years ago is thought to have brought water and complex molecules to our planet. This is a key process, which led to the existence of life.

Asteroids can be differentiated by their orbits (for example main belt asteroids, Trojans, near-Earth asteroids) and by their characteristics in the spectrum (asteroid taxonomy).

Ryugu (1999 JU3) falls into the very common category of near-Earth asteroids. These kinds of asteroids are of particular interest, because their spectrum is very similar to that of carbonaceous chondrites, which have a chemical composition that is very similar to that of the Sun and the early solar nebula. Furthermore, these asteroids have also been found to have hydrated minerals.  Finding answers to questions relating to the origin of life, and the origins and evolution of the Solar System are, therefore, the primary objective of MASCOT as a scientific payload of the Hayabusa2 mission.

Research on site and in the laboratory

The first Hayabusa mission by the Japanese Space Agency JAXA was a success: For the first time in 2010, the Japanese Hayabusa spacecraft used a capsule to bring materials from an asteroid back to Earth in their original, unaltered form. The DLR Institute of Planetary Research also had the opportunity to study this rare parcel. The Hayabusa2 mission is set to, once again, bring materials back to Earth, but will also take measurements directly on the asteroid, together with MASCOT. "Our data will, amongst other things, serve as a reference for studies conducted in laboratories here on Earth," said the DLR Project Manager Tra-Mi Ho. The lander will also act as a scout and explore the parts of the asteroid the Japanese probe should gather material from. "One thing is certain, both the probe and the lander will multiply the knowledge we have about asteroids".

DLR participation in the Hayabusa2 mission

The DLR Institute of Space Systems developed the lander and tested it in space conditions during parabolic flights, in the Bremen drop tower (ZARM), on the shake table, and in the thermal vacuum chamber at the Institute. The DLR Institute of Composite Structures and Adaptive Systems was responsible for the development of the lander's stable structure. The DLR Robotics and Mechatronics Center developed the arm that allows the MASCOT to jump. The DLR Institute of Planetary Research contributed to the MASCAM camera and the MARA radiometer. The MASCOT lander will be monitored and operated from the DLR Lander Control Center (LCC) at the Microgravity User Support Center (MUSC) in Cologne. CNES contributed to MASCOT's power subsystem, part of the telecommunications system, including the development of the antennas and the descent and landing mission analyses. Measurements of the asteroid's magnetization were conducted using the onboard Magnetometer MasMag that was developed by scientists of the TU Braunschweig. The IR Microscope MicrOmega was built and designed by scientists of IAS Paris.