EUV Observations of the Active Sun from the Harvard Experiment on ATM
Abstract
Some extreme UV observations of solar active regions made with a scanning spectroheliometer are described. Spectroheliograms constructed from digital data using a computer-driven cathode-ray tube display show clearly how the appearance of an active region changes as a function of temperature. Flare studies indicate that the impulsive rise in EUV emission occurs essentially simultaneously at all levels from the transition zone to the corona. Observations of sunspots reveal a very intense emission in transition zone lines. A matrix of Mg x rasters covering the entire sun reveals several hundred bright points having dimensions of 30 arc seconds or less. Other observations include coronal holes and prominences.
- Publication:
-
Solar Gamma-, X-, and EUV Radiation
- Pub Date:
- 1975
- Bibcode:
- 1975IAUS...68....3N
- Keywords:
-
- Emission Spectra;
- Far Ultraviolet Radiation;
- Line Spectra;
- Solar Activity;
- Solar Spectra;
- Apollo Telescope Mount;
- Chromosphere;
- H Alpha Line;
- Light Curve;
- Lyman Alpha Radiation;
- Solar Corona;
- Solar Flares;
- Solar Observatories;
- Solar Prominences;
- Spectroheliographs;
- Sunspots;
- Solar Physics