If you look at it from the perspective of "means of transportation," you realize that the rockets that are the means of transportation in space are still in their infancy. Automobiles were born around 250 years ago, railways around 200 and airplanes about 100 years ago.

Nevertheless, in a period of just 50 years it has become possible, for example, to touch down the Hayabusa2 on the asteroid Ryugu, collect sample and bring it back to the Earth which is quite incredible.

I believe that science has to be stringently scientific in every aspect. But as you say about the "heart" of Ohsumi being passed on to Hayabusa I also think that, as you suggest, the story of mankind is inherent in science and through this story I feel the profundity of science, and think it leads to an understanding of science. Currently, there are 5,700 publicly or privately funded museums throughout Japan, and since 2018 the administration of museums that had previously been under the jurisdiction of the Ministry of Education, Culture, Sports, Science and Technology (MEXT) was placed entirely under the Agency for Cultural Affairs. In other words, the science covered by museums is now a form of culture. Looked at from this perspective, I think that focusing on the story-like quality that science possesses is one possible course.

As you say, in terms of its story-like quality space exploration is something with a countless number of tales behind it. At a JAXA symposium held online in November 2020 we filmed and made public interviews with some of the people who had worked on the development of Ohsumi. Among these was, for example, the fact that the first four launches of the L-4S rockets all ended in failure. The fifth launch was finally successful, and some parts of the behind-the-scenes stories looked back on that day on February 11, 1970 when it was Ohsumi that was the very satellite to be sent into orbit around the earth. But it was the local people of the Ohsumi Peninsula who supported its launch and were its greatest backers. It was for this background that Ohsumi, Japan's first satellite, was named after the launch site, and this story is I believe one of the stories essential to the history of Japanese satellites.

One concrete example from the Science Museum about stories is that on the second floor of the Japan Gallery, among the livestock group that grew in tandem with the Japanese way of life, is displayed the stuffed "faithful dog Hachiko," a famous dog of the Akita breed. Actually until recently we exhibited the faithful dog Hachiko without revealing the story-like quality behind him. This was because we had wanted visitors to look at the stuffed animal from a purely scientific perspective. What I mean by scientific perspective is the point that humans tamed wolves, and after becoming a form of livestock turned into dogs, and eventually produced the Akita breed. We want visitors to properly appreciate that context. It was with this in mind that we tried to avoid drawing attention to the faithful dog Hachiko as a single specific animal, and exhibited him as something that was no more than one element in the livestock group.

What was it that led you to conduct the exhibition incorporating the present story-like quality?

It started with the fact that we received so many inquiries from the visitors to the Museum asking where the faithful dog Hachiko was. Looking at that situation we decided to provide a commentary explaining why it was that the faithful dog Hachiko had earned that name. Since we are a science museum we cannot drop our stance of stringent scientificity, but there is also all sort of fun to be had at the Science Museum. If one way of enjoying this is a story-like quality, we decided that we should adopt it. The story of the faithful dog Hachiko is just one example, and we intend to pursue at our museum diversity as a science museum.

Since you are an expert on biology I'd like to talk about something that will make you feel the connections between life and space exploration. The International Space Station (ISS) that is orbiting Earth at an altitude of around 400 kilometers is manned by astronauts conducting all sorts of experiments, and one of these is known as the Tanpopo Mission experiment or "the astrobiology exposure and micrometeoroid-capture experiments."

I have looked into the Tanpopo Mission myself. The experiments conducted on KIBO, the Japanese Experiment Module that is part of the ISS, enjoy the participation of a very large number of universities and researchers.

The experiments were conducted mainly by the Tokyo University of Pharmacy and Life Sciences and the JAXA Institute of Space and Astronautical Science, specifically by capturing the fine particles in space around Earth and analyzing them to see if the raw ingredients for life came to Earth from outer space or if, on the other hand, life originating from Earth is floating around in space. Furthermore, scientific investigations have been conducted with regard to whether it is possible for micro-organisms that live in extreme environments on Earth to survive when exposed to an outer space environment.

I believe that an experimental device was launched from the United States in 2015.

Yes, the device for capturing fine particles is made from a substance called "aerogel," which is an extremely light material similar to a jelly-like substance. The aerogel was installed on the exposed facility of KIBO, and has collected interstellar dust that is thought to contain organic matter such as amino acids and so on floating in space. The device was exposed to outer space for around one year, and was then brought back to Earth on a returning spacecraft. It was then exchanged for a new type of aerogel and the same process was repeated four times up until 2019. The analysis of it is currently underway.

Where and how did the advent of life on Earth, the origin of life itself take place? The theory that life was born on Earth itself is the most persuasive theory, but there is another school of thought called the "Panspermia hypothesis" that suggests that the building blocks forming the origins of life came from another celestial body. As far as I can understand it seems that in recent years the Panspermia hypothesis is being considered more seriously, and I saw the Tanpopo Mission as an attempt to verify various aspects of it through experiments.

This means that there was a movement of substances between Mars and Earth, and I can appreciate there is a fairly high possibility that this is what actually happened. But what about life? When considering that there are perhaps also movements of life, as the Panspermia hypothesis suggests life has moved from Earth to Mars and vice versa via celestial bodies. For example, if celestial bodies collide and the reaction of those collisions cause fine particles to explosively fly off the objects and travel between them, depending on when such events occur there is no doubt that they would have an influence upon life on Earth. Looking at it in this way expands our imagination.
*(The Tanpopo Mission has proved that it is possible for micro-organisms originating on Earth to survive in space for the three years that would be the shortest time span in which they could travel to Mars.)

The samples collected from the asteroid Ryugu by Hayabusa2 will shortly be returned to Earth [as of the time of the dialog, November 25, 2020], and as it is thought that the surface rock of Ryugu contains abundant organic substances by investigating these samples it may be possible to prove that the substances requisite for the advent of life on Earth were brought to us from outer space.

Indeed, it is thought that Ryugu contains not only organic matter, such compounds including carbon, but also water. These Carbon and water are the most basic elements of life, and its very building blocks. When we talk about these building blocks we are obviously on the path towards the question of the origins of life. So the imminent analysis of the samples from Ryugu is a matter of huge expectations on the part of scientists as it could bring us close to the origins of life, of the solar system, and of the universe itself.

The Science Museum is both a museum and simultaneously a research institute. We have over 60 researchers each pursuing their own research themes in the fields of natural history and the history of science and technology, so we always think how good it would be if we could collaborate with JAXA in some way, starting with the Ryugu samples.

Some of the irreplaceable disciplines in space engineering, my own area of expertise, are mathematics and physics, and I have liked them since my student days. Why did I like them? If I unravel the reasons for this we go back to the story-like nature that we mentioned earlier. I think one major reason was that I enjoyed reading the biographies of physicists such as Einstein and Newton, which eventually made me aware of the fact that physics and mathematics are very much a human discipline. Furthermore, Newton, for example, is known for discovering the principle of universal gravitation when he watched an apple fall, from which he stated that "force is proportional to the product of masses, and inversely proportional to the square of the distance between them." This is extraordinarily simple principle basically enabled us to express and describe about the movement of objects throughout the world. It enabled calculations and predictions about the future. And with the application of these sort of principles in space science, I as a researcher has been fascinated. So from my point of view the living organisms and life that are your specialization appear to be incredibly complex fields in comparison.

As you say, I also believe that that is where one of the attractions of science lies. I too have a personal fondness for physics, and up until entering university I must admit I hated biology! [laughs]. Take anatomy for example. There is a name for each and every of the over two hundred muscles, and you have to remember all of them. The etymology of all these muscle names brims over with interesting stories, but having to learn such a vast number of them was not a task suited to my personality. I really felt that strongly. What changed my way of thinking occurred after having entered university. There was still a mountain of things to remember but the depth of my fascination with the diversity of living things exceeded such thoughts.

What was the catalyst that sparked your fascination with the diversity of living things?

I think a large part of it was the environment in which I was brought up. I was born in Hiroshima but moved to my father's family home in Toyama around the age of two. The house was in an area surrounded by rice paddies, which are a place that it is difficult for children to play in. The one time of the year that I could play there was during winter. Snow fell and froze, and places where I couldn't usually walk became accessible. This is called "climbing on board the sky" in the Toyoma dialect, and I well remember playing in high spirits there. The result of this was that I gained a yearning for places like Hokkaido's pasture land and wanting to rear cows in a places like that became one of the reasons that I attended the school of veterinary medicine in the faculty of agriculture at university. In addition, from an early age I loved and read the works of MIYAZAWA Kenji, the children's story writer and dramatist, and in his writings around 160 species of animals appear. MIYAZAWA Kenji was a writer who thought continuously and profoundly about symbiosis between men and animals, and through his work in due course I too developed an interest in natural history.

And now you have fulfilled that boyhood dream, haven't you?

Yes, I think that I have been very lucky. And space probes can basically be manifested by Newton's laws, so it's a world that can be calculated. In other words, I became a researcher in the hope that through the world of simple space engineering I could make a contribution to the complex elucidation of life. I think it's possible to put it that way.

The biggest exhibit at the Science Museum is the YS-11, the one and only domestically produced aircraft.

From the point of view of JAXA as an organization dealing with space and aviation, the YS-11 storage by the Science Museum is something we are extremely grateful for.

The YS-11 is a propeller plane jointly developed by the public and private sector after the world war, and if you exclude prototypes, is the oldest Japanese airplane. It was maintained and stored by the Science Museum since 1999 at Haneda Airport. In the 2020, in order to enable as many people as possible to view it we moved it to the Hirosawa City theme park in Chikusei City, Ibaraki. The Science Museum stores all sorts of objects including the Mitsubishi A6M "Zero" fighter aircraft, and since an aviation museum has been created at the Hirosawa City theme park we hope in the future to continue exhibiting the aviation technologies in our collection.

That's certainly something to look forward to. As I said earlier, space engineering is supported by very simple principles, but the aerospace research and development that we carry out at JAXA is extremely multifaceted. For example, the growing issue of climate change by the year. We collect all sorts of data from space and the atmosphere and are pursuing initiatives to contribute to solving this issue, but something I always feel regarding this is that we won't be able to do so from a space and aviation perspective alone. In the final analysis, climate change is also connected to the oceans so unless there is collaboration with other fields of study we won't make progress in the true sense.

Carrying on from this, from the point of view of we at JAXA, solving the mysteries of space and life, and the space science and geoscience for widening mankind's knowledge are all important, but at the same time there is the question of what exactly is space and aviation in closely attached term to our daily lives. We want to continue with all sorts of research and development that originates from both of these perspectives.

Both the Science Museum and JAXA are targeting the whole public, regardless of age or gender. In this sense too, I would be very happy if we can attempt to collaborate with JAXA from all sorts of facets, and be of some assistance to public in deepening knowledge about the planet Earth, life and science and technology.

This would also delight us, and we look forward to working with you.