250 Bettina is a large main beltasteroid that was discovered by Austrian astronomer Johann Palisa on September 3, 1885, in Vienna. It was named in honour of Baroness Bettina von Rothschild (née de Rothschild; 1858–1892), wife of Baron Albert von Rothschild who had bought the naming rights for £50.[5] Based upon the spectrum, it is classified as an M-type asteroid.
In 1988, the asteroid was observed from the Collurania-Teramo Observatory, allowing a light curve to be produced that showed "an irregular behavior with a deeper minimum and a narrower maximum". The data showed a rotation period of 5.055 hours and a brightness variation of 0.17 ± 0.01 in magnitude. The ratio of the lengths of the major to minor axes for this asteroid were found to be 1.51 ± 0.03.[4]
^ abDotto, E.; et al. (June 1992), "M-type asteroids – Rotational properties of 16 objects", Astronomy and Astrophysics Supplement Series, vol. 95, no. 2, pp. 195–211, Bibcode:1992A&AS...95..195D.
^Observatory, vol. 8, p. 63, 1885 & vol. 9, p. 142, 1886; see also The Guinness Book of Astronomy Facts and Feats Patrick Moore page 96 ISBN0-900424-76-1