It was discovered on 10 November 1922, by Russian–French astronomer Benjamin Jekhowsky at Algiers Observatory in Algeria, North Africa.
[14] In 2012, a rotational lightcurve of Appella was obtained from photometric observations by American astronomer Robert Stephens at the Santana Observatory (646) in California.
It gave a long rotation period of 120 hours with a brightness amplitude of 0.4 in magnitude,[12] rendering a tentative 2006-observation by Italian astronomers Roberto Crippa and Federico Manzini obsolete.
[4][6][7][8][9][10] The Collaborative Asteroid Lightcurve Link (CALL) derives an albedo of 0.0609 and a diameter of 25.77 kilometers with an absolute magnitude of 11.60.
Although the figures are in accordance with the space-based surveys, CALL classifies Appella as a stony S-type rather than a carbonaceous C-type asteroid.