Overview

“Hayabusa2” is an asteroid sample return mission led by the Japan Aerospace Exploration Agency (JAXA). The main objective of this mission is to collect samples from the C-type asteroid Ryugu and bring them back to Earth. The “Hayabusa2” spacecraft measures approximately 1.0 x 1.6 x 1.25 meters, and when its solar panels are deployed, it spans about 6 meters in width.

“Hayabusa2” was launched on December 3, 2014, and performed an Earth swing-by on December 3, 2015. Subsequently, it arrived at the asteroid Ryugu on June 27, 2018. In 2019, it conducted two touchdowns to collect samples. The sample-containing capsule successfully returned to Earth on December 6, 2020. Currently, “Hayabusa2” has transitioned to an extended mission, planning to approach and observe the asteroid 1998 KY26.

Observation Instruments

Optical Navigation Camera (ONC)

ONC is composed of three framing cameras. One is a telescopic camera (ONC-T), and the others are a wide camera (ONC-W1 and ONC-W2). The ONC-T is a telescopic camera with seven band-pass filters in the visible and near-infrared range (0.40 - 0.95 micron) and one panchromatic band. These filters are placed on a wheel, which rotates to put a selected filter for different observations, enabling multi-band imaging.
This camera was used to capture detailed images of Ryugu’s surface, helping to analyze its terrain and surface features.

Thermal Infrared Imager (TIR)

TIR is based on an uncooled micro-bolometer array that can obtain thermal images of a target asteroid 162173 Ryugu (formerly 1999JU3). The TIR is the bolometric imager with a broadband filter in the thermal infrared range (8 to 12 um). It covers the temperature range of about 150 to 460 K and has a field of view of about 16.7 x 12.7 degrees, with 0.051 degrees per pixel (328 x 248). The primary objectives of this instrument are to investigate thermophysical properties of the surface of asteroids, such as porosity, grain size, and boulder abundance.

Near Infrared Spectrometer (NIRS3)

NIRS3 measures the spectral radiance of reflected sunlight from the asteroid. The spectral coverage is 1.8 to 3.2 µm to detect structural OH ions and H2O molecules.
The primary goal of NIRS3 is to map the distribution of hydrated minerals on the target near-Earth asteroid 162173 Ryugu.

Light Detection and Ranging (LIDAR)

LIDAR is a laser altimeter to measure the distance from the asteroid surface. It can measure range from 25 km to 30 m.
This allowed the spacecraft to accurately determine its altitude and ensured safe landings during touchdown operations. LIDAR uses a laser with a wavelength of 1064nm.

Mobile Asteroid Surface Scout (MASCOT)

MASCOT is an asteroid lander developed by the German Aerospace Center (DLR) and the French National Centre for Space Studies (CNES). It has a wide-angle camera (MASCAM), an infrared spectroscopic microscope (MicrOmega), a thermal radiometer (MARA), and a magnetometer (MasMag).
MASCOT landed on Ryugu’s surface to measure temperature, magnetic field, and surface physical properties.

Mobile Asteroid Surface Scout (MASCOT) Camera (MASCam)

The MASCam provides the ground truth for the orbiter remote sensing observations. MASCam contributes to the determination of the structural and compositional characteristics of the surface layer by means of panchromatic and multi-color imaging of the asteroid surface on scale lengths ranging from tens of meters to a fraction of a millimeter. The CMOS sensor of MASCam has 1024 x 1024 pixel sensitive in 400 - 1000 nm wavelength. During daytime, clear filter images will be acquired. During night, illumination of the dark surface is performed by a four-color LED array. The MASCam saved the image uncompressed in its internal memory. The image information was then transferred to the MASCOT onboard computer. The MASCOT onboard computer divided the 1024x1024x16 bit pixel image into 64 tiles with a size of 128x128x16 bit pixels each. These tiles were compressed using wavelet compression and stored for the next transmission to Hayabusa2.

Mobile Asteroid Surface Scout (MASCOT) Radiometer (MARA)

The primary science objective of the MASCOT Radiometer is a determination of the asteroid surface brightness temperature, which is achieved by measuring the net flux in two broadband infrared channels (8-14 and 5-100 microns). In addition, the instrument possesses 4 bandpass channels, which are used to constrain emissivity (5.5-7, 8-9.5, 9.5-11.5, and 13.5-15.5 microns).

obile Asteroid Surface Scout (MASCOT) Fluxgate Magnetometer (MasMag)

The relocation will provide a unique opportunity to measure magnetic fields at several locations, enabling higher confidence levels for the measurements as well as magnetic field gradient information. The MASCOT magnetometer instrument is a vector-compensated three-axis fluxgate magnetometer consisting of a sensor head and digital electronics. The sensor itself has been built at the Institut für Geophysik und extraterrestrische Physik (IGeP), Technische Universität Braunschweig in cooperation with Magson GmbH (Berlin) providing the electronics.

MicrOmega

MicrOmega is a near-IR hyperspectral microscope designed to characterize in-situ the texture and composition of the surface materials of Ryugu. The spectral range (0.99-3.65 micron) has been chosen to identify potential constituent materials.

Achievements

“Hayabusa2” successfully returned samples from Ryugu to Earth, promising numerous scientific discoveries. Initial analyses have confirmed the presence of organic matter and traces of water in the samples from Ryugu. These data are expected to significantly contribute to research on the formation and evolution of the solar system and the origins of life.