目に見えない光・電波望遠鏡
Radio telescope
写真:南米チリ(アルマ電波望遠鏡) 撮影・著者
Photo:Atacama Desert in Chile(ALMA)
Radio telescope
写真:南米チリ(アルマ電波望遠鏡) 撮影・著者
Photo:Atacama Desert in Chile(ALMA)
目に見えない光である電波をパラボラアンテナを使って観測する望遠鏡。
A telescope that uses a parabolic antenna to observe radio waves, which are invisible light.
南米チリ・アタカマ砂漠(アルマ電波望遠鏡建設場所)赴任時の写真集(^^♪!
Photographs from when I was assigned to the Atacama Desert in Chile, South America (where the ALMA radio telescope was built)
アルマ電波望遠鏡建設地(写真:著者)ALMA radio telescope construction site
電波望遠鏡の歴史と技術
History and technology
of radio telescopes
When was the radio telescope made? It was built by Karl Jansky in the United States about 88 years ago.
Photo: World's first radio telescope.
About 68 years ago, Jan Oort of the Netherlands observed the spiral structure of the Milky Way galaxy and the position of the solar system with a radio telescope.
Scientists around the world started radio telescope observations with this as an opportunity.
Radio telescopes in the world after that
About 30 years ago, Japan was looking for observation sites in the vast dry land of the world and was planning a large-scale radio telescope.
At the same time, similar plans were being made in the United States and Europe.
It was decided that each plan would be combined to create an ideal telescope that could not be realized in one country or region.
The photo I took below is of the ALMA radio telescope.
The mechanism of radio telescopes is almost the same as that of satellite broadcasting.
Radio telescope technology
The antenna mirror surface has an unevenness of 25 microns or less
The antenna moving part uses a linear motor for both up, down, left, and right.
parabolic antenna
Radio waves from space are reflected by a dish and collected by a small dish at the focal point.
receiver
Radio waves from the parabolic antenna are changed to a lower frequency (4 to 12 GHz) and amplified by the receiver.
The amplified radio signal is converted into a digital signal and transmitted through an optical fiber.
send to supercomputer
ALMA uses 10 bands from 31GHz to 950GHz
correlator
Digital signal sent by optical fiber from each antenna
Correlation processing (combining the signals from each antenna in time, superimposing the signals, correcting the positional relationship of each telescope and time lag)
Extract information such as brightness, position and velocity of celestial bodies. Further image processing is performed to generate a radio wave image.
Sixty-six ALMA radio telescopes were built in the Andes Mountains at an altitude of 5,000m in the Atacama Desert, Chile.
Alma means soul in Spanish.
The 66 ALMA radio telescopes will be huge telescopes as wide as the inside of the Yamanote line in Tokyo.
小中高生向け講演会資料より
From lecture materials for elementary, middle and high school students
私たちの天の川銀河の中心にある巨大ブラックホール・いて座Aスターの姿を、ついに捉えましたね、素晴らしい(*^-^*)!2017年から2年がかりで初めてブラックホールの姿を日本も参加の国際プロジェクト「EHT」が捉えたのが、2019年の「M87」銀河!次は天の川銀河と言われ3年目、凄いです!(写真提供:EHT)
You've finally captured the style of the giant black hole "Sagittarius A Star" in the center of our Milky Way galaxy, wonderful! The 2019 "M87" galaxy captured the style of a black hole for the first time! The international project "EHT", in which Japan also participates, has achieved great achievements. Next was said to be the Milky Way Galaxy. I caught the style in just the third year. It's amazing!
長野県野辺山にある45ⅿの電波望遠鏡。ミリ波の電波を観測できる電波望遠鏡としては世界最大口径をほこる。1982年から日本の電波観測を引張っぱり、銀河の中心の巨大ブラックホール存在を世界初確認。 (写真提供:NAOJ)
A 45-m radio telescope located in Nobeyama, Nagano Prefecture. It has the largest aperture in the world as a radio telescope that can observe millimeter-wave radio waves. This radio telescope has been pulling radio observations in Japan since 1982, confirming the existence of a huge black hole in the center of the galaxy for the first time in the world.
アルマ望遠鏡は南米チリ標高5000ⅿのアタカマ高地に建設された、世界最大級66台のパラボラアンテナ電波望遠鏡群です。アルマとはAtacama Large Millimeter/submillimeter Arrayの頭文字で、意味はスペイン語で「魂」。(写真:著者撮影)
The ALMA telescope is a group of 66 parabolic antenna radio telescopes, one of the largest in the world, built in the Atacama Highlands at an altitude of 5000 ⅿ in Chile, South America. Alma is an acronym for Atacama Large Millimeter / submillimeter Array, meaning "soul" in Spanish.