About a dozen local astronomy clubs have arranged for their city libraries to acquire telescopes that can be lent to patrons. The story comes from Sky & Telescope for October 2014: “Check Out This Telescope!” by John Jardine Goss. He tells of the Adams Library in Chelmsford, Massachusetts. They accepted an offer from the New Hampshire Astronomical Society (NHAS) which had been supporting this program in their communities for six years.
When we moved to Kyle in December 2021, I got a library card before I updated by driver’s license. (In 1990-1992, I served on the White House Commission on Libraries and Information Services. I held a taxpayer’s Michigan State University Libraries card for many years when we lived in central Michigan and I depended heavily on them while writing for the numismatic trade periodicals.) The Kyle City Library had two board seats vacant. So, I applied and was appointed by the city council on 12 April 2022. Bringing the telescope project seemed like a good way to serve.
In the Sky & Telescope story, the instruments were tabletop Dobsonian (“dob”) variety Newtonian reflectors. That choice was broadly supported by other clubs who took the idea to their community libraries. For one thing, the lack of a tripod is not a barrier and removes one set of problems. For another, these tend to be in the 4-inch (100 mm) range, which is more than sufficient to explore the Moon, the planets, large clusters, and other targets easily available in the cities and suburbs.
The NHAS also developed a set of modifications to make viewing easier as well as to prevent tampering. Even so, in one case one telescope came back in pieces because the patron made the effort to disassemble it. There are a few other less horrible horror stories. Overall, based on internet chat group reports, perhaps as many as 200 of these telescope are being loaned from about 60 different libraries. Problems were exceptions. Nonetheless, lessons were learned.
The library staff gets training on the instruments so that they understand their functions, pieces, and parts. And the staff is the first to borrow the new acquisitions. A check-out/check in form with a checklist helps to guide and audit the process. One discussion of projects similar to this one is in the Outreach forum of the Cloudy Nights board here:
Among the very many impacts of Covid were the contraction of in-person patronage at the libraries and the collapse of the supply chain for astronomers. Our city library is back on track. However, I found that the makes and models popular in 2008-2019 are no longer on the market as product lines were consolidated. So, I went shopping.
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| https://shop.astronomerswithoutborders.org/collections/frontpage/products/awb- onesky-reflector-telescope |
Easiest for myself, I bought a 130-mm (5-inch) reflector from Astronomers Without Borders. I am a sustaining member of AWB and was their Person of the Month some time back. The AWB dob was created in partnership with Celestron which writes off a portion of their costs in order to allow maximum profits to the not-for-profit to carry out its international outreach. Nice as that all is, the open-truss configuration is problematic as a library loaner. It is too accessible to the overly curious patron.
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| https://explorescientificusa.com/collections/national- geographic-telescopes/products/national-geographic- 76mm-table-top-reflector-telescope |
I also acquired a National Geographic 76-mm (3-inch) from Explore Scientific for $89. It was $20 cheaper from Adorama from Amazon but I chose to pay more because Explore supports the hobby in direct ways by sponsoring star parties and publishing a free online magazine and providing customer service. Their CEO Scott Roberts also serves on the board of Astronomers Without Borders. This model is more amenable to reconfiguration. For myself, I like finding the lower limits of power and have logged binary stars, nebulae, and other targets with 70-mm refractors. “What can you see with that?” is an honest question and I can give a strong answer.
For both of these, I already have other tripods that can be put to use. The AWB comes with a Vixen-style bar which is nearly universal in the hobby. Each of these can sit on a round wooden plate bolted to a different Celestron camera tripod that I have.
These will help to inform the library board and the library director about the kinds of choices and their capabilities. The library loaner will need a “zoom” eyepiece. These oculars change their focus points and therefore their effective magnification. They are about twice as expensive (at least) as a good mid-range eyepiece but this is will make viewing easier for the patron and obviate the losses to the library. In any case, neither of these tabletop dobs comes with quality oculars. Today, the 4-lens Plössl eyepiece (also appearing as Ploessl or Plossl) is the baseline but these arrive with simpler Huygens, Ramsden, and Kellner configurations.
For myself, I have seen nebulae and separated binary stars with the “value-priced” attachments, but the fact remains that better glass delivers more subtle details. Also, among the modern oculars are several series with much wider fields of view (FOV) than their 17th, 18th, and 19th-century ancestors. Right now, my preferred eyepieces are a 14-mm 82-degree FOV Meade Series 5000 and a 7-mm 82-degree FOV Nagler Type 1. They will do well in the new Dobsonians.
[Note: It was the late John Dobson (1915-2014) who pioneered large reflector telescopes on wooden “lazy susan” swivel mounts. He ground the mirrors from porthole plate glass retrieved from ship salvage yards. After living in a Hindu monastery, he took his astronomy to the streets. See Wikipedia here: https://en.wikipedia.org/wiki/John_Dobson_(amateur_astronomer) and YouTube here: https://www.youtube.com/watch?v=bVbX19kabNc ]
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