This blue object is the Sun. Scientists at the National Solar Observatory use a Spectroheliograph to capture this image, daily. Ionized calcium emits blue light that is sensitive to magnetic fields. Thus, magnetically active structures on the Sun appear in contrast to their surroundings, allowing researchers to observer solar activity.
Courtesy of the National Solar Observatory

This blue object is the Sun. Scientists use special equipment to create this image. This type of photograph of the Sun allows scientists to find places on the Sun’s surface where there are sunspots and other solar activity.
Courtesy of the National Solar Observatory

This blue object is the Sun. Scientists use special equipment to make the Sun blue. The blue Sun helps scientists to see the sunspots.
Courtesy of the National Solar Observatory

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