Auroral forms | Article about auroral forms by The Free Dictionary
auroral forms[ə′rȯr·əl ′fȯrmz]
Auroral display types, of which two are basic: ribbonlike bands and cloudlike surfaces.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive
These aren't the well-known aurora that can light up the sky at high latitudes, but rather weaker and more distant aurora known as Poleward Moving Auroral Forms
(PMAF) that can only be seen from very dark locations on Earth.
An Arctic field manual of 1875 noted that the variety of auroral forms
was so great that "no definite rules can be laid down for observing them.
Sitting next to my magnetometer (3,4) in Edinburgh it was possible to compare changes in auroral forms
with corresponding changes in the Earth's magnetic field.