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Admiring stars/私の趣味

posted Jan 24, 2017, 3:48 PM by PARC Osaka University   [ updated Jan 24, 2017, 3:54 PM ]

I love to “let others look at” stars.

The beginning of my interest in “looking at” stars was the astronomical telescope my grandfather bought for me when I was in the second year of junior high school. On the day the astronomical telescope arrived, I took it outside and tried to focus on the brightest star in the sky right away. It was really difficult for me to adjust the telescope at first. No sooner had I finally made it than I realized that the star had rings around it. It was Saturn. How pretty it was, I was amazed, and thought I saw something important. The time was probably about 8pm. I would have looked at the moon, if there had been the moon. Instead, Saturn was shining in the southeast. Just recently I checked with an astronomy simulation software and found out that was in mid October of 1968.

Saturn I saw that night surely ushered me into the world of stars later in my life. In 1968, a year prior to the first moon landing of the mankind, Apollo 8 became the first manned spacecraft which orbited the moon and returned safely to Earth. The spacecraft back from 380,000 km away reentered the atmosphere of Earth at a speed of 10km per second. They said the spacecraft must reenter the atmosphere in a certain angle with an allowable error range of 2degree. If the angle was deeper, the spacecraft would be burned down, and, if shallower, it would be bounced back. I remember I was so thrilled with the television coverage of Apollo 8.

As a child, I wondered if I could see the Apollo spacecraft orbiting the moon through my telescope. There is no way, definitely, for my telescope could only distinguish craters of 4km in diameter of the moon surface. Strange to say though, I felt like I was able to see the spacecraft. The actual moon through the telescope showed me something much more than what it looked, and that was so different from the moon in a photograph.

As I grew older, stars more and more intrigued me. I have been all the way to New Zealand to see the stars in the southern hemisphere, and to the tip of California Peninsula to see the total solar eclipse.

Now my friends and I hold star-viewing gatherings on a monthly basis at the Floating Garden Observatory on the top of the New Umeda Sky Building. We give a talk about stars which can be seen on the day, as well as some topics on astronomy or space. Three or four astronomical telescopes are brought to the venue. Most of the participants are so impressed and raise cheers to see stars and planets through the telescope for the first time in their life.

This is how I changed from just “looking at” stars on my own to “letting others to look at” stars.

The moon light we now see is in fact the light of the sun reflected 1.3 seconds ago. The actual photons departed from the moon surface come into our eyes through the telescope, stimulate the retinal cells, and convey the visual image to the brain. In this system, I believe, something happens more than just a visible image. I guess this somehow explains why the vision through the telescope fascinates the participants.

The light wavelength our eyes can detect is approximately from 400nm in blue to 700nm in red. Light, in a broad meaning, is called electromagnetic waves, which also include these invisible light; X rays, gamma rays, IR rays, radio waves and many other. Although the invisible light has led us to various scientific discoveries and inventions, the visible light, which we can sense directly, stirs our imagination and creativity much more than that.

Thus, that is the theme of “Photonics”, in my own interpretation. Maybe my life has long been connected to the Photonics Center. I will try best to be able to contribute the Center.

January 25th, 2017

Hiroshi  Osumi, Photonics Center

















フォトニクスセンター 大角泰史