What's New Under The Sun

Sunday, 24 March 2024 18:30

There are lots of maps showing where to go for the April 8th 2024 total solar eclipse and others showing the statistical chance of clouds such as https://www.washingtonpost.com/weather/2024/02/22/april-eclipse-clouds/  From Little Rock Arkansas to the Mazatlan coast there is a high probability of clear weather.  The cities from Indianapolis through Cleveland OH, Rochester and Syracuse...

Sunday, 24 March 2024 01:42

When is a watch not a watch? When it unfolds into an equatorial sundial.  The watch, designed by Yu Ishihara is called a "Watch Exclusively for Sunny Men" and was part of a contest sponsored by Seiko to "help reimagine what a watch can be", aimed at creativity and perhaps for eventual production. Read about it at...

Wednesday, 06 March 2024 00:17

  Dr. Federica Gigante, from Cambridge Univerity's History Faculty, discovered a rare astrolabe sequestered in a museum at Verona, Italy.  Publishing in Nuncius (1 March 2024) Dr. Gigante presents "a hitherto unknown remarkable astrolabe from Al-Andalus which likely belonged to the collection of Ludovico Moscardo (1611–1681) assembled in Verona in the seventeenth century. The...

Friday, 23 February 2024 17:42

The North American Sundial Society (NASS) will hold its 2024 conference in Vancouver, British Columbia, Canada from Thrursday June 20th to Sunday June 23rd.  The conference will  be held at the Fairmont Hotel Vancouver, 900 West Georgia Street, Vancouver BC.  The conference will start Thursday afternoon with a traditional reception and sundial door prizes.  Friday will be a...

Friday, 23 February 2024 16:53

Spanish sundialist Esteban Martínez has launched the resolution to establish the World Sundial Day to occur each year on the Spring Equinox.  According to the petition circulated by Martinez, "Reason  Sundials represent the union of disciplines as disparate as Astronomy, Mathematics, [and] Geography...They have an undoubted didactic value in teaching astronomy to young people and as...

Saturday, 18 November 2023 18:21

NASS is pleased to announce the upcoming third instance of Elements of Dialing, our introductory course about sundials, their history, and the science that makes them work. The free 13-lesson course, intended for those are new to sundialing, runs from January 2024. The course coordinator will be Steve Lelievre, our Secretary and editor of The Compendium. Steve will be assisted from time to time...

Sunday, 05 November 2023 16:30

Smithsonian Magazine holds a photo-of-the-day contest. Winner on 30 Oct 2023 was Harita Sistu who took a photo of the large sundial of Jantar Mantar, Jaipur India (taken in July 2022). Harita notes: "I wanted to try my best to capture just how massive the instrument is and bring focus into the incredible skill that went into designing and constructing it." See other NASS...

Friday, 14 July 2023 23:08

A sundial or performance center or solar generator? It's all three. Called the Arco del Tiempo (Arch of Time), the design by Berlin architect Riccardo Mariano provides the projection of the sun's rays onto the ground through tinted glass apertures spanning the length of its arching ceiling. The elliptical shaped spots change every hour, telling "the solar time each day and delight visitors with...

Saturday, 01 July 2023 00:36

According to NewAtlas.com (https://newatlas.com/architecture/sun-tower-open/), construction of the Sun Tower exhibition building and outdoor theater is underway in the Chinese city of Yantai. The tower is being constructed by a French firm, Ducks Sceno and the engineering firm Arup, raising to 50m (164 ft) gracefully into the sky.  The tower symbolizes the historic watch towers of...

Sunday, 25 June 2023 22:17

Julie Baumgardner in The Art Newspaper of Jan 13, 2023 reports on the construction project of Point of Infinity, a nearly 70 foot (21m) hyperbolic cone will reach toward the sky as part of a 50 million dollar park development on Treasure Island and Yerba Buena Island. In a competition held by the San Francisco Arts Commision on behalf of the Treasure Island Development Authority, Hiroshi...

Thursday, 30 March 2023 00:03

In the Swiss mountains near the resort of Zermatt just beneath the Matternhorn, Stir World reports that "famed luxury Swiss watchmaker Hublot announced Daniel Arsham as its new ambassador, with a compelling piece of temporary land art. Aptly titled "Light & Time", the work is a Hublot-inspired 20-metre sundial resting in the shadows of the Matterhorn mountain." This sculptural is billed as...

Sunday, 18 December 2022 23:00

Sklar Bixby and Jeremy Meel, students at Santa Fe College in Florida took on a project to design and 3D-print a new sundial for the Kika Silva Pla Planetarium in Gainesville Florida (located on Santa Fe's Northwest Campus). Under the guidance of Dr. Philip Pinon, Sklar and Jeremy took on a semester long project as part of the Exploring Honors Mathematics class. They designed a horizontal sundial...

Foster1652PosthumaFosteri

Samuel Foster. Posthuma Fosteri: THE DESCRIPTION OF A RULER, Upon which is described divers SCALES:

AND The Uses thereof: Invented and written by Mr. SAMUEL FOSTER, LateProfessor of ASTRONOMIE in GRESHAM COLLEDG. By which the most usuall Propositions in Astronomie, Navigation, and Dialling, are facily performed. Also, a further use of the said Scales in Deliniating of far declining dials; and of those that Decline and Recline, three severall wayes. With the deliniating of all Horizontall Dials, between 30, and 60 gr. of Latitude, without drawing any lines but the Houres themselves. LONDON: Printed by ROBERT and WILLIAM LEYBOURN, for NICHOLAS BOURN, at the South entrance into the Royall Exchange. 1652.    (90 pages, 9.8 MB)

This book was published posthumously in the year that Foster died. It describes a ruler with 9 scales and gives instructions on how to use the scales to solve many of the standard problems of “astronomie, navigation, and dialling”. In addition to familiar trigonometric scales, the ruler includes two new scales introduced by Foster. The first provides an easy means of laying out horizontal dials between 30º and 60º of latitude without having to draw any auxiliary lines.

The second is an innovation that Foster identifies simply as the C scale. With this scale and a chord scale, Foster is able to find all the elements needed to draw a dial on an arbitrary plane. He also uses these scales to replace the usual dialing scales, laying out a sundial from equispaced points on the circumference of a circle. [ By reversing this process, a sundial that uses a standard clock face can be designed. ] One page of the current edition includes a redrawn version of the ruler that the reader can use in conjunction with the text.

This can be ordered from LuLu Books: Foster: Posthumi Fosteri - The Description of a Ruler (1652)