1304 Arosa

It was discovered on 21 May 1928, by German astronomer Karl Reinmuth at Heidelberg Observatory in southwest Germany.

[1] It was first identified as A908 YC at the discovering observatory in 1908, extending the body's observation arc by 20 years prior to its official discovery.

The Wide-field Infrared Survey Explorer (WISE) groups it into the metallic M-type asteroid subcategory.

Lightcurve analysis gave a well-defined rotation period of 7.74 hours with a brightness amplitude between 0.32 and 0.38 magnitude (U=3/3/3/2).

[5][6][7][8][9] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.2125 and a diameter of 41.67 kilometers, using an absolute magnitude of 9.2.