It was discovered on 27 August 1935, by Soviet astronomer Pelageya Shajn at the Simeiz Observatory on the Crimean peninsula.

[1] The hydrated carbonaceous C-type asteroid has a rotation period of 8.4 hours and measures approximately 42 kilometers (26 miles) in diameter.

[12] In June 2011, a rotational lightcurve of Ostanina was obtained from photometric observations by French and Swiss astronomers Pierre Antonini, François Colas, Valery Lainey, Laurène Beauvalet and Raoul Behrend.

Other well defined rotation periods of 8.399 and 8.397 hours were obtained by Robert Stephens at the Center for Solar System Studies (U81) in California in 2017, and by V. G. Shevchenko at the Kharkov Observatory (101) in 1996, respectively (U=3/3).

[5][6][7][8][9] The Collaborative Asteroid Lightcurve Link adopts the results obtained by IRAS, that is, an albedo of 0.0545 and diameter of 41.24 kilometers using an absolute magnitude of 10.7.