Editing Perkins Observatory (section)

==The 69-inch Perkins of 1931==
[[File:ReflectingTelescope 017.jpg|thumb|The 69 inch glass blank for the main mirror of the telescope]]
The 69-inch Perkins was the 3rd largest telescope in the World when it came online in 1931.<ref name=":1"/>

;Contemporaries at first light:
{| class="wikitable" style="font-size: 90%; text-align: center;"
|-
! style="background: #BBEEFF;" | #
! style="background: #BBEEFF;" | Name /<br /> Observatory
! style="width:40px; background: #BBEEFF;" | Image
! style="background: #BBEEFF;" | Aperture
! style="background: #BBEEFF;" | Altitude
! style="background: #BBEEFF;" | First <br />Light
! style="background: #BBEEFF;" | Special advocate
|-
|-
! 1
| [[Hooker Telescope]] <br> [[Mount Wilson Observatory|Mount Wilson Obs.]], United States
| [[File:100inchHooker.jpg|30px]]
| 100&nbsp;inch <br> 254&nbsp;cm
| 1742 m <br/>(5715&nbsp;ft)
| 1917
| [[George Ellery Hale]] <br/> [[Andrew Carnegie]]
|-
!2
| Plaskett telescope <br/>[[Dominion Astrophysical Observatory|Dominion Astrophysical Obs.]], Canada
| [[File:Dominion Astrophysical Observatory front.jpg|40px]]
| 72&nbsp;inch <br> 182&nbsp;cm
| 230 m <br /> (755&nbsp;ft)
| 1918
| [[John S. Plaskett]]
|-bgcolor="efefef"
!3
| 69-inch Perkins Telescope, United States<ref>{{cite web|url=http://www.perkins-observatory.org/history.html |title=History |publisher=Perkins Observatory |date=1 August 1998 |accessdate=5 March 2012 |url-status=dead |archiveurl=https://web.archive.org/web/20060928085124/http://www.perkins-observatory.org/history.html |archivedate=28 September 2006 }}</ref> || || 69&nbsp;inch <br>175&nbsp;cm   ||  ||1931  || Hiram Perkins || 
|}

In 1961 the telescope was moved out from Perkins Observatory, and eventually the 69 inch mirror was put in a museum. The 69 inch was replaced with a new 72 inch mirror in the 1960s, which is why it was later called the 72 inch Perkins, not the 69 inch.

It was featured in a telescope exhibit at one point, but was eventually walled in a closet and thus not available for viewing.<ref name="perkins.owu.edu">[http://perkins.owu.edu/69inch_mirror.htm The Story of the 69-Inch Mirror Move]</ref> The mirror was returned to Perkins observatory by 1999, and was put on display.<ref name="perkins.owu.edu"/> The mirror was the first large mirror cast in the United States and probably the third largest telescope mirror in the World when it came into use in 1931.<ref name="perkins.owu.edu"/> The mirror blank weighed 3000 pounds and was cast in 1927 by the United States Bureau of Standards.<ref name=":3">{{Cite journal|date=1932-01-01|title=69-in. Mirror for Perkins Observatory|journal=Nature|language=en|volume=129|issue=3244|pages=17|doi=10.1038/129017c0|bibcode=1932Natur.129S..17. |issn=1476-4687|doi-access=free}}</ref> It needed 8 months to cool properly.<ref name=":3" />

The Perkins telescope, with the 72 inch mirror, was sold to Lowell Observatory in 1998.<ref name="Thursday">{{Cite web|url=https://astronomy.com/magazine/news/2018/10/lowell-observatory|title=Lowell Observatory enters new age|first=David J.|last=Eicher|date=October 25, 2018|website=Astronomy.com|access-date=2019-10-14}}</ref> The evolved version of the Perkins is located at Anderson Mesa in Arizona, where it is now used by that Observatory and other universities.<ref name="Thursday"/>