Tools for Solar Observation

Abstract

The Sun is a main-sequence star of average mass, luminosity, and effective temperature — one of about 10¹¹ in our galaxy. The only distinction is that the Sun is much closer to us. Next to the Sun the nearest star, α Centauri with its companions, is more than 10⁵ times farther away. This has two consequences: First, the Sun is the only star where details on the surface can be spatially resolved; and second, the flux of radiation from the Sun is so intense that many studies which cannot be undertaken with other stars are possible, in particular those which simultaneously require very high spectral resolution and high resolution in space and time.