department still calls itself Leiden Observatory. In much of astronomy, the data came from elsewhere and could be analyzed and studied on the campus; for example in modern times the instruments may even be located in space, with data transmitted back to Earth and then studied on a computer display. (An example of this was the Astronomical Netherlands Satellite, launched in 1974.) The archive of the Leiden Observatory is available at Leiden University Library and digitally accessible through Digital Collections Einstein's Chair in the Ten-inch dome Einstein's Chair is an astronomical observing chair at the Leiden Observatory. This chair, made in 1861, is the only piece of furniture in the observatory that dates from that time. The chair gets its name from the fact that it was used by Albert Einstein on several occasions during his visits to the observatory. Einstein was a frequent visitor of the building during his professorship at Leiden university due to his good friendship with the director, Willem de Sitter. The chair can be found in the largest dome of the observatory, the so-called 10-inch dome (named after the 10-inch telescope that is placed inside). The chair is still used by observers and a popular attraction at the observatory. On 21 October 2015, Einstein's Chair got a short segment on the Dutch astronomy program Heel Nederland Kijkt Sterren. During this segment the science populariser Govert Schilling and the science historian David Baneke talked about its origins. Einstein is noted for his visits to Leiden Observatory during World War I. Restoration The old Observatory building facilities (from 1860s) was restored in the 2010s. While not longer the base for the modern Leiden Observatory academically, it does have the astronomical historical items at the facility. Also, a solar telescope was crowd funded to provide live optically transmitted images of the Sun to the Visitor center, which is also known to have offered tours. Gallery Directors Instruments Examples: Zes-Duims Merz Refractor (ch objective with wooden telescope tube dating to 1830s) Ten-inch Repsold Refractor ( ch Alvin and Clark objective lens on Repsold und Söhne, since 1885) Photographic Double Refractor (since 1897) Zunderman Reflector (46 cm diameter mirror (~18.1 inches), since 1947) Heliostat See also Timeline of telescopes, observatories, and observing technology List of largest optical telescopes in the 19th century References Further reading Telescopes from Leiden Observatory and other collections. 1656 - 1859 (.pdf) From attics to domes: