31641 Cevasco

31641 Cevasco (provisional designation ) is a stony Nysian asteroid from the inner regions of the asteroid belt, approximately 3.3 kilometers in diameter. It was discovered on 6 April 1999, by the Lincoln Near-Earth Asteroid Research project at Lincoln Laboratory's Experimental Test Site in Socorro, New Mexico, United States. The asteroid was named for Hannah Cevasco, a 2015 Broadcom MASTERS awardee.

Orbit and classification
Cevasco orbits the Sun in the inner main-belt at a distance of 2.1–2.8 AU once every 3 years and 10 months (1,390 days). Its orbit has an eccentricity of 0.13 and an inclination of 1° with respect to the ecliptic.

The asteroid's observation arc begins 6 years prior to its official discovery observation, with its first identification as at ESO's La Silla Observatory in 1993.

Lightcurves
Three rotational lightcurves of Cevasco were obtained from photometric observations at the Palomar Transient Factory between 2010 and 2014. Lightcurve analysis gave a rotation period of $2.737$, $2.656$ and $2.817$ hours with a brightness variation of 0.71, 0.48 and 0.54 magnitude, respectively (U=2/2/2).

Diameter and albedo
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Cevasco measures 2.7 kilometers in diameter and its surface has an albedo of 0.311, while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for a stony asteroid of 0.20 and calculates a diameter of 3.3 kilometers with an absolute magnitude of 14.8.

Naming
This minor planet was named in honor of Hannah Olivia Cevasco (born 2000) finalist in the 2015 Broadcom MASTERS, a math and science competition for middle school students, for her medicine and health sciences project. At the time she attended the St. Charles School in California.