Walter Grotrian

Walter Robert Wilhelm Grotrian (April 21, 1890 in Aachen; † March 3, 1954 in Potsdam) was a German astronomer and astrophysicist.

Grotrian studied the emission line from the solar corona in the green region of the spectrum; this emission line could not be attributed to any known chemical element and was thought to be a new element (which scientists named "coronium"). Grotrian and Bengt Edlén from Sweden demonstrated that the two observed emission lines arise from iron atoms that have lost about half their 26 electrons.[1]

Named after Grotrian

The impact crater Grotrian on the Moon
The Grotrian diagram in atomic spectroscopy showing the allowed transitions between atomic energy levels
Character in "Time Keeps on Slippin'" episode of Futurama

Persondata
Name	Grotrian, Walter
Alternative names
Short description
Date of birth	1890
Place of birth
Date of death	1954
Place of death