High Quality Content by WIKIPEDIA articles! The University of Illinois Astronomical Observatory was constructed in 1896. It stands on South Matthews Avenue in Urbana, Champaign County, Illinois. The observatory was listed on the National Register of Historic Places on November 6, 1986 and on December 20, 1989, the U.S. Department of Interior designated the observatory a National Historic Landmark. Though none of the astronomical instruments are being used for professional research today, the observatory still contains a 12" Brashear refractor. The observatory played a key role in the development of astronomy as it was home to a key innovation in the area of astronomical photometry. The facility has been directed by such noted scientists as Joel Stebbins and Robert Horace Baker.