It was discovered on 6 April 1922, by Russian–French astronomer Benjamin Jekhowsky at the Algiers Observatory in Northern Africa.
[2] Philippa is a non-family asteroid of the main belt's background population when applying the hierarchical clustering method to its proper orbital elements.
[5][10] In April 2004, a rotational lightcurve of Philippa was obtained from photometric observations by Brian Warner at the Palmer Divide Observatory in Colorado.
Analysis of the classical bimodal lightcurve gave a rotation period of 15.405±0.005 hours with a high brightness amplitude of 0.49±0.02 magnitude, indicative of an irregular, non-spherical shape (U=3) [11][9][a] According to the survey carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Philippa measures between 65.4 and 65.9 kilometers in diameter and its surface has an albedo between 0.05 and 0.06.
[6][7][8] The Collaborative Asteroid Lightcurve Link adopts the results from IRAS, that is, an albedo of 0.0555 and a diameter of 65.67 kilometers based on an absolute magnitude of 9.67.