4257 Ubasti was discovered by J. E. Mueller, an American astronomer and discoverer of comets, minor planets, and a large number of supernovas at the U.S. Palomar Observatory in California, on 23 August 1987
It was discovered by American astronomer Jean Mueller at the Palomar Observatory in California on 23 August 1987. Jean Mueller (born 1950) is an American astronomer and discoverer of comets, minor planets, and a large number of supernovas at the U.S. Palomar Observatory in California. 
J. E. Mueller 23 August 1987 Jean Mueller (born 1950) is an American astronomer and discoverer of comets, minor planets, and a large number of supernovas at the U.S. Palomar Observatory in California. 
