Calcium K-line Full-Disk Spectroheliograms
- Period: 1917-1974
- Instrumentation: Grubb 30-cm sidelostat, Cooke 18cm/Steinheil 13.5cm Objective lenses, Toepfer double-prism Spectroheliograph (Photos are provided by Public Relations Center)
- Spectral window: 0.5Å
- Recording device: Photographic plate (1917-1960)/35mm film (1960-1974)
- Telescope Site: Azabu (1917-1924) and Mitaka (1925-1974), Tokyo, Japan
- Number of images: 8585
- Number of observing days: 8524
Calendars and javascript movies of jpg files
- The celestial north is roughly to the top, and the west is roughly to the right.
- A filename, "caYYYYMMDD_nnn.jpg", shows the date with YYYYMMDD and the daily image number with nnn.
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- The celestial north is roughly to the top, and the west is roughly to the right.
- A filename, "caYYYYMMDD_nnn.jpg", shows the date with YYYYMMDD and the daily image number with nnn.
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- These preliminary fits files contain raw scanned data. The header of each file includes various kinds of information as follows.
- BSCALE positive (1) or negative (-1) image
- CRPIXn approximate position of the disk center
- SOLR_PIX approximate radius of the disk in pixels
- CDELT1 positive (1) is to the west, negative (-1) to the east
- CDELT2 positive (1) is to the north, negative (-1) to the south
Last update: Dec. 10, 2011
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