Discovered by E. L. Johnson MPC designation 1609 Brenda Discovered 10 July 1951 Orbits Sun Discovery site Union Observatory | Discovery date 10 July 1951 Minor planet category main-belt · (middle) Absolute magnitude 10.61 Discoverer Ernest Leonard Johnson Asteroid group Asteroid belt | |
Named after Brenda (discoverer's granddaughter) Alternative names 1951 NL · 1925 EA
1934 JB · 1947 WB
1950 HD · 1954 EP
1954 HE People also search for Sun, 1568 Aisleen, 1623 Vivian | ||
1609 Brenda, provisional designation 1951 NL, is a stony asteroid from the middle region of the asteroid belt, approximately 28 kilometers in diameter. It was discovered on 10 July 1951, by South African astronomer Ernest Johnson at the Johannesburg Observatory in South Africa.
The S-type asteroid orbits the Sun at a distance of 1.9–3.2 AU once every 4 years and 2 months (1,518 days). Its orbit has an eccentricity of 0.25 and an inclination of 19° with respect to the ecliptic. Brenda was first identified as 1925 EA at Simeiz Observatory in 1925. Its observation arc begins 17 years prior to its official discovery observation, with its identification 1934 JB, also made at Simeiz.
American astronomer Richard P. Binzel obtained the first rotational light-curve of Brenda in June 1984. It gave a rotation period of 19.46 hours with a brightness variation of 0.16 magnitude (U=2). In June 2006, a period of 7001230000000000000♠23±1 with an amplitude of 0.26 magniutde was derived from photometric observations made by French amateur astronomer René Roy (U=2).
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite, and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Brenda measures between 26.27 and 29.64 kilometers in diameter, and its surface has an albedo between 0.115 and 0.133. The Collaborative Asteroid Lightcurve Link derives an albedo of 0.1078 and a diameter of 29.59 kilometers using an absolute magnitude of 10.68.
This minor planet was named by the discoverer for his granddaughter, Brenda. Ernest Johnson is also known for the discovery of the periodic comet 48P/Johnson, using the Franklin-Adams Star Camera. Naming citation was published before November 1977 (M.P.C. 3931).