The Helium Filtered Sun

Calcium K
Helium 1
Soft X-ray
No Filter

What features do you notice in this picture?

This image was taken through a filter which only allows radiation with a wavelength of 1083 nanometers to pass through. This wavelength corresponds to infrared radiation, or heat. Radiation of this wavelength comes from ionized Helium atoms in the Sun. This image was taken by a telescope at the Kitt Peak National Solar Observatory in Arizona.

Before this radiation leaves the Sun some of it is absorbed by dense gas in the Sun's atmosphere. These dense regions appear dark because there is no radiation of this wavelength left to make it to the camera.

This image provides information about a layer of the Sun above that seen in the Calcium image.

When you have viewed all the images of the Sun let's discuss what we have seen.

The Calcium Filtered Sun Filters Lesson The X-ray Filtered Sun