Well-BeingExploring the origins of life

After about six years of traveling through space, the asteroid explorer Hayabusa2 delivered samples from Asteroid (162173) Ryugu to the Earth in December 2020. These samples will provide information on the origin and the evolution of the Solar System, including the beginning of life, the organic materials that compose life, and where the water that is present originated. The Astromaterial Science Research Group (ASRG) of the Institute of Space and Astronautical Science (ISAS) manages the Extraterrestrial Sample Curation Center (ESCuC) that conducts the curatorial work of JAXA's return samples and leads planetary science at JAXA. Nikon's microscopes are being utilized to aid in this cutting-edge research.

Asteroid Ryugu

Hayabusa2: Unraveling the secrets of asteroids.

The Japan Aerospace Exploration Agency (JAXA) is an organization with 20 centers throughout Japan, as well as five international bases. JAXA's primary purpose is to contribute to society by conducting a wide range of activities in the aerospace field, from basic research to the development and utilization of groundbreaking technologies. We visited JAXA, at the Institute of Space and Astronautical Science (Sagamihara Campus) where various subjects related to the entire universe such as the activities of the sun, the origin of the moon, planets, black holes, and galaxies are thoroughly researched. The Sagamihara Campus is also the home base of the asteroid explorers Hayabusa and Hayabusa2.

We interviewed Dr. Akiko Miyazaki, a researcher in the Astromaterials Science Research Group at the Institute of Space and Astronautical Science. One of the roles of ASRG is management of ESCuC that conducts the curatorial work of the JAXA's return samples, such as samples from Itokawa (Hayabusa) and from Ryugu (Hayabusa2). The initial description identifying the characteristics of these samples is performed by members of ESCuC (curators). Dr. Miyazaki is a curator and is involved in management, analysis and description of Ryugu samples.

Japan Aerospace Exploration Agency (JAXA),
Institute of Space and Astronautical Science,
Astromaterials Science Research Group
Akiko K. Miyazaki


  • 20-min. walk from the south exit of Fuchinobe station on the JR Yokohama line
  • Kanachu bus (Fuchi 36 or 37 Aoba loop line) from Fuchinobe station on the JR Yokohama line
    (2-min. walk from City museum bus stop)
  • Kanachu bus (Ai 05 to Sagamihara sta. south exit) from the north exit of Sagamiono station on the Odakyu line
    (10-min. walk from Onodai 3-chome bus stop)
    Kanachu bus (Ai 02 to Sagamihara sta. south exit) from the north exit of Sagamiono station on the Odakyu line.
    (5-min. walk from JAXA bus stop)
JAXA's Sagamihara Campus Main Gate

The cosmic time capsule delivered by Hayabusa2.

What kinds of cosmic secrets might be revealed by the samples from Ryugu? The answer will be related to the properties of asteroids. Our solar system is said to have been born 4.6 billion years ago. Initially, various gases and dust gathered in a vortex, condensed by their mutual gravitational pull, and what is known as the 'primordial sun' formed in the center. Following this, planetesimals*1 several kilometers in diameter accumulated from the remaining gas and dust. These planetesimals repeatedly collided and fused, with some forming the planets we know today. During this process, innumerable small asteroids*2 that did not coalesce into planets were left over. Itokawa, which was explored by Hayabusa, and Ryugu, visited by Hayabusa2, are both considered to be these types of asteroids.

Hayabusa2 and the Earth (CG)
© Akihiro Ikeshita

“Ryugu is designated as a C-type asteroid and is considered to be related to carbonaceous chondrites (meteorites) that fly to the earth," says Dr. Miyazaki. She added, “Like carbonaceous chondrites, C-type asteroids are considered to be rich in water and organic materials. These might still be present in such asteroids as they were when the Solar System was forming. Ryugu is like a time capsule. It could provide clues as to the origin of life and water of the Earth."
In December 2020, when Hayabusa2 passed closest to the Earth, it released a capsule containing samples taken from Ryugu and safely delivered them to the Earth. Since then, Hayabusa2 has been continuing its journey of exploration to new targets on its extended mission.

Re-entry fireball of capsule released from Hayabusa2
  • *1Small celestial bodies created in the early stages of planetary system formation such as in the solar system.
  • *2Minor celestial bodies excluding planets and dwarf planets of the solar system and their satellites, they exist mainly within the orbit of Jupiter.

Microscopes help reveal the secrets of the samples.

The total amount of samples from Ryugu delivered by Hayabusa2 to Earth weighed only 5.4 grams – but was more than 50 times the target of 0.1 grams. The materials were in the form of a black sand, with some particles being several millimeters in size, which was a great surprise that went beyond previous expectations.
A dedicated clean room and clean chamber*1 were prepared for handling the Ryugu samples. The clean room where the microscope is installed provides air cleanliness that is about 10,000 times that of a normal office. The interior of the chamber is filled with high-purity nitrogen. This is to prevent any influence of air and dust. In this environment, the samples of sand grains and fine particles are placed individually in special dishes for observation and analysis.

The clean room and clean chamber
Samples delivered by Hayabusa2
Dish to hold sample specimens

Nikon's SMZ1270i is a stereomicroscope used to observe the color, shape, and size of each sample. However, the observation procedure differs radically from the norm since the special samples are located in the clean chamber and observed through a window above the chamber. The microscope itself is attached to a large stage which moves in XYZ directions, which is unique. You can see how it looks in the video content posted at the beginning of this article.

Nikon's SMZ1270i is mounted above the clean chamber
The microscope can move in XYZ directions

Ryugu sample photographed under a microscope

Microscopic image of sample (1)
Microscopic image of sample (2)

"While I've been observing them, I've been thinking that each grain has its own stories to tell. I would like to hear the stories of every grain. I'd like to open up these tiny time capsules*2." said Miyazaki.

We hope that Nikon's microscopes will continue to help researchers in their challenge of unraveling the mysteries of life, the Earth, and the cosmos from the minute fragments of a long-lost universe.