Given a question and a context passage, generate the answer having the word or phrase from the context passage. Here, the answer should be a shortest continous span from the passage.

Context: 9767 Midsomer Norton (1992 EB1) is an outer main-belt asteroid discovered on March 10, 1992 by Duncan Steel at Siding Spring.
Question: Who made the discovery of 9767 Midsomer Norton?
duncan steel