<< < Abb dec lep pos Wol > >>
A number indicating the degree of → sunspot
→ sunspot number and
→ relative sunspot number.
Named after Johann Rudolf Wolf of Zurich who introduced the number in 1852;
Same as → atomic number.
Z, from the German word Zahl "number, numeral, figure,"
which was used to specify an element's numerical place in the
→ periodic table; → number.
© 2005-2022 by M. Heydari-Malayeri