The Sun is the only star for which we can observe fine details on its surface and investigate the associated activity. Once the underlying physics has been established, it can be applied to the understanding of other activities in the Universe.

The Domeless Solar Telescope (DST) was designed to acquire solar surface images at the highest spatial resolution. Since its establishment in 1979, the DST has contributed to the great scientific progress in recent years in the understanding of the mechanisms which cause solar explosive events, and other phenomena in space plasma physics.

There are two types of spectrographs attached to the DST: A vacuum vertical spectrograph which has the highest wavelength resolution in the world, and a horizontal spectrograph that can image the entire visible solar spectrum. These two spectrographs are used to study the physical properties of small-scale solar atmospheric structures and explosive events.
[Details about the vertical spectrograph (Japanese)]
[ Details about the horizontal spectrograph (Japanese)]

The DST Lyot filter has a very narrow passband of 0.25 angstroms, and provides arbitrary wavelength tuning. With this filter, we can see the three-dimensional velocity structure of the solar atomosphere.

The file sizes are somewhat large, so it may take some time to download them.

1. Automatic guide to make the telescope point toward the Sun. [QuickTime (4.5MB)], [GIF animation (4.9MB)]
2. To open the entrance lid and let in the Sun's light. [QuickTime (7.2 MB)], [GIF animation (7.4MB)]
3. At the start of daily operations, the observer searches for an object suitable for the scientific purpose of his research, such as a prominence, some emerging flux, spots, etc. When the object comes into the field of view, the observer can look at its 3D structure by changing the observed wavelength. [QuickTime(14 MB)], [GIF Animation(32 MB)]