Before the late 1800s, little was known about the three layers of the solar atmosphere: the photosphere, the chromosphere, and the corona. It was only during total eclipses of the Sun--a time period amounting to only a few minutes a year--that astronomers were able to even begin examining the details of solar phenomena. The chromosphere and the corona comprise the outermost layers of the Sun's total atmosphere. Activities and conditions of scientific importance, such as such as sunspots, prominences, spicules, and flares, occur in both areas. These conditions can be studied with a solar telescope, a reflecting (or refracting) telescope, modified with special spectral instruments.

Creation of the first solar telescope took place in two separate areas of the world: the United States and France. American astronomer George Ellery Hale (1868-1938) began developing the spectrohelioscope in 1889. Combining a telescope with a spectroscope, the spectrohelioscope separates the...