CLASSIFICATION OF SOLAR PROMINENCES. XII. SUMMARY FOR 1944 TO 1954
Abstract
The areas and behavior classifications of the prominences on the sun during solar cycle no. 18 are summarized, and a study is presented of the distribution of the various classes with respect to solar latitude. For all classes combined and for each, except the spicules, separately, activity reached a maximum near spot maximum in 1947 and a minimum nearly two years before spot minimum in 1954. During this solar cycle, 93% of the prominences were of A types in which the material descended from the corona, and 20% were of S types, associated with sunspots. The biggest class of prominences was the AN or hedgerow family; the smallest, the BN's or spicules. The overall trend in the prominence areas was thus due mainly to the AN prominences. Ratios of prominence areas to spot areas decreased from 1944 to 1947 and increased rapidly in 1953 and 1954. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1961
- Accession Number
- AD0265756
Entities
People
- Donald H. Menzel
- F. Shirley Jones
Organizations
- Harvard College