Discovered by P. Wild MPC designation 1657 Roemera Minor planet category main-belt · (inner) Orbits Sun Asteroid group Asteroid belt | Discovery date 6 March 1961 Alternative names 1961 EA · 1932 AB Discovered 6 March 1961 | |
Similar 1930 Lucifer, Sun, 3552 Don Quixote, 81P/Wild, Themisto | ||
1657 Roemera, provisional designation 1961 EA, is a stony asteroid from the inner regions of the asteroid belt, approximately 8 kilometers in diameter. It was discovered on 6 March 1961, by Swiss astronomer Paul Wild at Zimmerwald Observatory near Bern, Switzerland.
Roemera is a stony S-type asteroid. It orbits the Sun at a distance of 1.8–2.9 AU once every 3 years and 7 months (1,315 days). Its orbit has an eccentricity of 0.24 and an inclination of 23° with respect to the ecliptic. Roemera was first identified as 1932 AB at Heidelberg Observatory in 1932, extending the body's observation arc by 29 years prior to its official discovery observation.
In May 2008, American astronomer Brian D. Warner obtained a rotational light-curve of Roemera from photometric observations at his Palmer Divide Observatory in Colorado. It gave a longer than average rotation period of 34.0 hours with a brightness variation of 0.15 magnitude (U=2). Polish astronomer Wiesław Z. Wiśniewski found a different period solution of 4.5 hours with a low amplitude of 0.09 magnitude in March 1990 (U=2).
According to the survey carried out by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Roemera measures 7.66 kilometers in diameter and its surface has an albedo of 0.220, while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 8.04 kilometers based on an absolute magnitude of 12.89.
This minor planet was named by the discoverer in honor American astronomer Elizabeth Roemer (b. 1929), U.S. Naval Observatory, in appreciation of her untiring and successful efforts to advance the knowledge of the motions and physical properties of comets and minor planets. Roemer herself discovered the asteroids 1930 Lucifer and 1983 Bok. Naming citation was published before November 1977 (M.P.C. 2347).