61 Danaë

Danaë (minor planet designation: 61 Danaë) is a stony (S-type) asteroid in the outer asteroid belt's background population, approximately 84 kilometer in diameter. It was discovered by French astronomer Hermann Goldschmidt on 9 September 1860, from his balcony in Paris, France. Goldschmidt was ill when asked to name the asteroid, and requested his fellow asteroid-hunter Robert Luther to name it instead. Luther chose to name it after Danaë, the mother of Perseus in Greek mythology. Danaë was the first asteroid to have a diacritical character in its official name.

The asteroid is orbiting the Sun with a period of 5.15 years and is rotating on its axis once every 11.45 hours. In 1985, a study of lightcurve data suggested that Danaë may have a moon. If so, the main body would be an ellipsoid measuring 85 ×, and the moon would orbit 101 km away, measuring 55 ×. The density of both would be $82.04$.