1267 Geertruida, provisional designation 1930 HD, is a carbonaceous background asteroid from the inner regions of the asteroid belt, approximately 20 kilometers in diameter. Discovered by astronomer Hendrik van Gent at Johannesburg Observatory in 1930, the asteroid was later named after Geertruid Pels, sister of Dutch astronomer Gerrit Pels.
Geertruida was discovered on 23 April 1930, by Dutch astronomer Hendrik van Gent at the Union Observatory in Johannesburg, South Africa. Five nights later, it was independently discovered by German astronomer Karl Reinmuth at Heidelberg Observatory on 28 April 1930. The Minor Planet Center only recognizes the first discoverer. The asteroid was previously identified as 1926 GV at Heidelberg Observatory in April 1926.
Geertruida is a non-family asteroid from the main belt’s background population. It orbits the Sun in the inner asteroid belt at a distance of 2.0–2.9 AU once every 3 years and 11 months (1,417 days; semi-major axis of 2.47 AU). Its orbit has an eccentricity of 0.18 and an inclination of 5° with respect to the ecliptic. The body’s observation arc begins with its official discovery observation at Johannesburg in April 1930.
Geertruida is an assumed carbonaceous C-type asteroid, which agrees with its measured albedo (see below).
In 1977, a rotational lightcurve of Geertruida was obtained from photometric observations by Swedish astronomer Claes-Ingvar Lagerkvist at the Uppsala Southern Station in Australia. Lightcurve analysis gave a rotation period of 5.50 hours with a brightness amplitude of 0.5 magnitude (U=2). In October 2016, a refined period of 5.5087 hours with an amplitude of 0.35 magnitude (U=3) was obtained at the Oakley Southern Sky Observatory (E09).