Editing Palomar Observatory (section)

===Decommissioned instruments===
* An {{Convert|18|inch|cm|adj=mid}} [[Schmidt camera]] became the first operational telescope at the Palomar in 1936. In the 1930s, [[Fritz Zwicky]] and [[Walter Baade]] advocated adding survey telescopes at Palomar, and the 18-inch was developed to demonstrate the Schmidt concept.  Zwicky used the 18-inch to discover over 100 [[supernovae]] in other galaxies. [[Comet Shoemaker-Levy 9]] was discovered with this instrument in 1993. It has since been decommissioned and is on display at the small museum/visitor center.<ref name=18IN>{{cite web |title=Caltech Astronomy – The 18-inch Schmidt Telescope |url=http://www.astro.caltech.edu/palomar/about/telescopes/decommissioned.html#p18 |publisher=Caltech Astronomy |access-date=2014-12-09}}</ref><ref name=":1">{{Cite web |title=Greenway Visitor Center |url=https://sites.astro.caltech.edu/palomar/visitor/visitorcenter.html |website=sites.astro.caltech.edu}}</ref>
* The [[Palomar Testbed Interferometer]] (PTI) was a multi-telescope instrument that made high-[[Angular resolution|angular-resolution]] measurements of the apparent sizes and relative positions of stars.  The apparent sizes and in some cases shapes of bright stars were measured with PTI, as well as the apparent [[orbits]] of multiple stellar systems. PTI operated from 1995 to 2008.<ref name=PTI>{{cite web |title=Caltech Astronomy – Palomar Testbed Interferometer (PTI) |url=http://www.astro.caltech.edu/palomar/about/telescopes/decommissioned.html#pti |publisher=Caltech Astronomy |access-date=2014-12-09}}</ref>
* The Palomar Planet Search Telescope (PPST), also known as Sleuth, was a {{Convert|10|cm|in|abbr=|adj=mid}} robotic telescope that operated from 2003 until 2008. It was dedicated to the search for planets around other stars using the [[Astronomical transit|transit]] method. It operated in conjunction with telescopes at [[Lowell Observatory]] and in the [[Canary Islands]] as part of the [[Trans-Atlantic Exoplanet Survey]] (TrES).<ref name=PPST>{{cite web |title=Caltech Astronomy – Sleuth: The Palomar Planet Finder |date=30 October 2009 |url=http://palomarskies.blogspot.de/2009/10/goodbye-to-sleuth.html |publisher=Palomar Skies |access-date=2014-12-09}}</ref>