NRAO NSF had decided on a National Radio Astronomy Observatory, NRAO A 100- meter class steerable dish antenna was being considered Too expensive for

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1 WHY KITT PEAK National Science Foundation Grants to enhance astronomy departments Partially fund new telescopes for astronomy departments Key Options addressed at Flagstaff meeting A. Funding many 36-inch telescopes for various astronomy departments the option favored by many departments or B. One 80-inch telescope accessible to individual observers Advocated by Leo Goldberg and McMath NSF favored option B National Optical Astronomy Observatory, NOAO How did I get involved?

2 NRAO NSF had decided on a National Radio Astronomy Observatory, NRAO A 100- meter class steerable dish antenna was being considered Too expensive for a single observatory to build It would provide access to all radioastronomers Should be close to East Coast radio astronomers Thus close to WDC AUI was selected to implement this plan to build a large steerable dish Bart Bok and Aden Meinel were Regents on the Board of AUI Bok and I were selected to make a site survey Recommended a site at Greenbank, West Virginia For a 100 meter diameter steerable dish antenna

3 NOAO NSF wanted recommendations on a National Optical Astronomy Observatory NSF already decided to support 36-inch telescopes For individual universities The question was what about much larger telescopes McMath was asked to form an ad hoc committee to make recommendations A contract was given to the University of Michigan I was selected as Executive Secretary to the McMath Committee My role with AUI and Greenbank may have entered into why I was selected by McMath I don t really know

4 NOAO But Bengt Stromgren, one of the McMath panel, did know I don t know if my experience with NRAO was a factor in this choice But Bengt Stromgren, a member of the McMath panel, did know about my role with AUI and Greenbank. My role gradually grew from Executive Secretary to do, ad hoc, the site survey. And to design and build Telescopes and support facilities Upon their completion I was to serve one year as Director of KPNO After which I joined the University of Arizona This report describes the Site Survey and Why Kitt Peak was chosen.

5 SITE CONSTRAINTS The site was tightly constrained by practical considerations to within the continental US At the lowest SW latitude Presumably out of phase with weather affecting the California observatories No higher than 8,000 ft altitude For ease of sleeping not expected to be affected by nearby city lights for ~ 50 years ease of access by visiting astronomers amenities attractive to NOAO staffing & families These criteria limited the choice to a narrow strip of southern Arizona and New Mexico

6 THE SITES 4 potential sites were chosen, 3 in northern Arizona and 1 in southern Arizona

7 THE SITES 4 potential sites were chosen, 3 in northern Arizona and 1 in southern Arizona 1) Hualapai Peak, near Kingman

8 THE SITES 4 potential sites were chosen, 3 in northern Arizona and 1 in southern Arizona 1) Hualapai Peak, near Kingman 2) Summit Peak, near Williams, on the Flagstaff plateau

9 THE SITES 4 potential sites were chosen, 3 in northern Arizona and 1 in southern Arizona 1) Hualapai Peak, near Kingman 2) Summit Peak, near Williams, on the Flagstaff plateau 3) Chevalon Butte, on the Mogollon plateau SW of Winslow

10 THE SITES 4 potential sites were chosen, 3 in northern Arizona and 1 in southern Arizona 1) Hualapai Peak, near Kingman 2) Summit Peak, near Williams, on the Flagstaff plateau 3) Chevalon Butte, on the Mogollon plateau SW of Winslow 4) Kitt Peak, a desert peak SW of Tucson

11 THE SITES We added the California observatory sites plus Unipero Serra, a peak south of Monterey overlooking the fog-shrouded Pacific Ocean An amateur telescope builder had his 20-in telescope there when Pierce and I visited The astronomical seeing was excellent I saw fine details on Mars that I had never seen before

12 THE SITES This map shows what we weren t aware of The Pacific winter storm tracks would pass over the three northern Arizona sites A day or to later after the California sites But Kitt Peak would be on the summer monsoon rains of Arizona

13 THE ARIZONA SITES Northern Sites The Hualapi and Summit sites had limited areas, but at that time only two telescopes were planned, a 36-inch and an 80-inch.

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16 THE ARIZONA SITES Northern Sites The Hualapi and Summit sites had limited areas, but at that time only two telescopes were planned, a 36-inch and an 80-inch. The Chevelon Butte had an extensive plateau region that could accommodate many telescopes.

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18 THE ARIZONA SITES Northern Sites The Hualapi and Summit sites had limited areas, but at that time only two telescopes were planned, a 36-inch and an 80-inch. The Chevelon Butte had an extensive plateau region that could accommodate many telescopes. Southern Site The Kitt Peak site had an extensive summit region that could accommodate multiple telescopes

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20 THE ARIZONA SITES Southern Site Its location on the Tohono O odham Tribal Reservation offered protection from the expansion of Tucson to the west Kitt Peak quickly became the focus of attention by the McMath panel. There were three problems our access to the mountain was blocked no access by any vehicle the Indian name was Home of the Clouds a potential embarrassment to the McMath panel and NSF Permission was finally granted and our first ascent of Kitt Peak was on horseback.

21 ACCESS TO KITT PEAK Limited NSF funds posed a problem Pima County Highway Division offered use of their heavy-duty road construction machinery Project would pay only the operators A rough trail was bulldozed to the summit up the steep eastern side The maximum grade over most of this trail was 100% (45 slope) The 16-in telescope and the test tower and testing operations were hauled up over this trail

22 ACCESS TO KITT PEAK A gentler access roadway was required for the construction of the telescopes and support facilities A 27% grade access roadway was constructed The public access road was prohibitively expensive, more than the $3,000,000 NSF funding for the entire project The McMath panel soon decided that Kitt Peak was the most important site.

23 Movie of first ascent

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26 TEST TOWERS A 50-ft tower enabled the telescope to sample the seeing well above ground effects It consisted of two concentric structures The seeing telescope structure was protected by a completely separate outer tower that was additionally stiffened by cables

27 TEST TOWERS But aerodynamic coupling between the two towers caused continuing problems All four sites essentially showed the same seeing disc size Pressure mounted to make a decision and get on with building the National Optical Astronomy Observatory on Kitt Peak

28 FACTORS CONSIDERED Key factors definitive in selecting Kitt Peak were 1) The relative isolation of Kitt Peak from Tucson 2) Rail and surface facilities to minimize construction costs 3) The Tucson community for city offices 4) A city site offered by the University of Arizona 5) Housing and schools for the Tucson staff

29 THE LEASE Negotiations had been started very early looking toward a lease of the summit region for the observatory The key event leading to approval by the tribe was a visit to Steward Observatory for the first look at the Moon by the members It established that the men with the long eyes really needed the excellence of their mountain for the National Optical Astronomy Observatory The lease signing at the schoolhouse for the Shuk Toak region soon completed everything and engineering for the construction program shifted into high gear.

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