--- Canopus56 <canopus56@yahoo.com> wrote: <snip all> Offline --- Rob Ratkowski <ratkwski@hawaii.rr.com> asked:
A sundial in SLC ?? How cool is that?? Do you have any photos of the installation ?? I ask because I'm
part of the group designing the public observing area for the visitor information center for the proposed ATST (Advanced Technology Solar Telescope) to be built on Haleakala. My design is based on a barchan to be the wind block and I suggested that the top of the barchan wind block we place a gnomon to create a sundial.
Rob, here are some pics of the Matsubayashi-Gallivan Center sundial. - A blogger pic, probably one of the better ones. http://www.jasonbennion.com/photos/albums/Misc/Asteroid_Landed_Softly.jpg http://www.jasonbennion.com/archives/000135.html - A small picture at the bottom of this page of the Center's website. http://www.slcgov.com/PublicServices/Gallivan/location.htm Since the Center's picture was taken, a large office building was built to the southwest (shown in the blogger pic). So the dial really only works from around 10am to noon. A brief quote from the architect on the dial: "You can look at the sundial and watch the shaft of light moving, making its way across the dial, and think about what time means. A woman with terminal cancer came up to me once and said it meant a lot to her to look at it and contemplate the reality of time in our brief life spans." http://www.slweekly.com/editorial/2002/arts_2002-07-11.cfm I have corresponded with Prof. Matsubayashi via email. He did not know about the technical details of the sundial implementation. He is an artist/architect. He stated that he had a civil engineer lay the dial out. The three main books on sundials are: Sundials: Their Theory and Construction (Paperback) by Albert Edmund Waugh Paperback: 228 pages Publisher: Dover Publications (December, 1973) Language: English ISBN: 0486229475 List: $8.95; Amazon: $8.95 Sundials: Their Construction and Use [UNABRIDGED] (Paperback) by R. Newton Mayall, Margaret W. Mayall Paperback: 250 pages Publisher: Dover Publications; Unabridged edition (August, 2000) Language: English ISBN: 048641146X List: $12.95; Amazon: $10.36 Sundials : History, Theory, and Practice (Paperback) by Rene R.J. Rohr Paperback: 176 pages Publisher: Dover Publications (July 9, 1996) Language: English ISBN: 0486291391 $16.96 List; $10.85 Amazon I believe Mayall's book has some interesting design samples from the 1950s, e.g. - sundials on science research buildings at odd angles that may be useful for your proposed application.
My design is based on a barchan to be the wind block . . .
Which side of the sanddune shape will face the sun? I'd assume the working side of the facility is in the north-facing concave wind shadow and you are looking at a gnomnon at the crest casting a shadow into the north side. But maybe the windy side is to the east or west. http://en.wikipedia.org/wiki/Barchan Are you planning to cast the shadow on the barchan concave shape (harder)? Or are you planning to cast the shadow onto the flat horizontal plaza at the base of the barchan's concave side (simplier)? A rare vertical declining north-facing sundial (to get the gnomon shadow on the concave barchan shape) might work. http://www.mysundial.ca/tsp/vertical_declining_sundial.html http://www.mysundial.ca/tsp/vertical_direct_north_sundial.html See also http://www.mysundial.ca/tsp/cube_sundial.html If the sun is on the convex side and the concave side is in shadow most of the time, Waugh's book at Chap. 14 has an interesting couple of pages on reflected light sundials. That would also get the dial light on the shadow side of the barchan. But if you are planning to use the plaza, that's a straight-forward horizontal dial. I have not read Rohr's book yet. She may have something on a circular equilateral or parabolic dial that would be suitable for the barchan shape. Or maybe you can get some inspiration from Jantar Mantar in India http://www.jantarmantar.org/ http://www.ifa.hawaii.edu/~yan/india/jm.html or the giant modern sundial at Montbéliard, France. http://perso.wanadoo.fr/blateyron/sundials/montbeliard1.html The "Sundial Primer" site has examples of many different sundial forms and an updated "links" page to all the major sundial associations in the U.S. and abroad. http://www.mysundial.ca/tsp/tsp_index.html The "Sundial Primer" site uses printouts from a software package called "Shadows" that you might find useful. Apparently it is cripple-shareware, but it is not expensive. It looks useful for roughing out designs for complex shapes. http://perso.wanadoo.fr/blateyron/sundials/shadowspro/gb/index.html - Canopus56(Kurt) __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com