What's New Under The Sun
Easy Dial Adjustment for Your Latitude & Longitude
Sunday, 02 April 2023 20:13
Suppose that you've purchased a commercial sundial and you want to make it work correctly for your latitude. Further, you don't live on your time zone meridian, but are some kilometers/miles east or west of that longitude line.
Steve Lelievre has written a web app that allows you to build a wedge to hold the sundial. You can use the calculator to simply make a latitude wedge...
Ice Sculpture Ephemeral in Time
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...
Register Now for NASS 2023 Conference
Monday, 16 January 2023 01:21
The NASS Conference comes early this year. Register now for the 28th annual NASS Conference in Ann Arbor, Michigan June 8-11, 2023
KensingtonHotel, Ann Arbor Michigan
Ann Arbor is best known as the home of the sprawling University of Michigan with its architecture, quadrangles, and bustling student life. Yet, it also boasts of great art, science, and archeological...
New Sundial for Kika Silva Pla Planetarium
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...
NASS Dialist Don Snyder Passes
Saturday, 10 December 2022 17:41
Don Snyder, long time NASS member, sundial designer and conference organizer, died Nov. 21, 2022 at the age of 87. He organized two St. Louis conferences for NASS in 2008 and 2017. For the first St. Louis conference, Don worked closely with Michael Olsen of the Missouri Botanical Garden to have five sundials available for viewing, including the dedication of a dial donated by Ron Rinehard, the...
Today - Chicagohenge
Thursday, 22 September 2022 20:41
The date is Sep. 22, 2022, the date of the fall equinox. Although this is supposed to be the day of equal day and night, we know it's not exactly correct. We measure daytime from sunrise to sunset, measured as the first and last light from the sun peaking over the horizon. When we include sunrise and sunset plus atmospheric refration, at mid latitudes daylight wins by about 10...
Indiana French Dial Found
Saturday, 27 August 2022 19:06
Smithsonian Collection - Pocket sundial by Bourgaud of Nantes, 1660–1675. (MA.325565)
From the National Museum of American History is an article about "How did a French pocket sundial end up buried in a field in Indiana?" published 20 July 2022 by Kidwell & Schechner.
It started in 1860 when Dr. Elisha Cannon, while plowing a field in Indiana, came...
2022 - Frans Maes
Tuesday, 23 August 2022 14:17
The 2022 Sawyer Dialing Prize went to Frans Maes "for his creation of an introductory course on dialing, built on the idea of supervised self-study; for his successful multi-year running of that course in Europe; and for his inspiration of NASS’ development of a North American version.”
Fred presented Frans with an award certification, the traditional cash prize of $250 and a custom made...
Interview with Sasch Stephens
Tuesday, 09 August 2022 21:32
What makes a sundial? Practically anything. Sasch Stephens discusses how he became interested in dialing. Since then he has turned many objects into solar time devices. It takes some creative thinking to invision how a common object can become a working sundial. One of the most recent projects turned a 54 x 28 foot south side of a building it into a giant sundial...
World's Smallest Sundial Gets a Lot Smaller
Sunday, 12 June 2022 22:00
Dr. Jeremy Robinson, (Naval Research Laboratory, Electronics Science and Technology Division) combined efforts with his father-in-law, Prof. Woodruff Sullivan (Univ. of Washington Dept. of Astronomy) to construct the World's Smallest Sundial. The competition was sponsored by Cadrans Solaires pour Tous and their record is being entered into the Guiness Book of World...
Guiness Record for Smallest Sundial
Saturday, 28 May 2022 17:28
Perhaps the smallest sundial goes to IBM with the printing of a sundial in a corner of a computer chip. However it lacked a gnomon and could not really tell the time. However, Chen Fong-shean, a Taiwanese miniature craftsman, was challenged by the French astronomical society to beat the Guiness World Record for smallest sundial held by an Italian. The Italian dial created in...
British Sundial Society Founder Christopher Daniel Passes
Wednesday, 25 May 2022 14:42
NASS is saddened to report the passing of one of the UK’s pre-eminent sundial designer, Christopher St. J H Daniel who died on May 17, 2022. His works are to be found all over the UK, ranging from private commissions to major public works and to restorations and reconstruction of old and damaged sundials.
After a 13-year career at sea, Christopher Daniel joined the staff of the National...
Dial 'Down Under' Acquired by Historical Museum
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[photo credit: Port Macquarie Historical Society]
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[photo credit: Port Macquarie Historical Society]
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The words “sundial” and “convict” are not often used in the same context, but that is the situation in Port Macquarie, Australia when a vintage sundial made around 1840 was put on permanent display at the Port Macquarie Historical Museum. The dial was made by colonial engraver Raphael Clint and was once owned by Danial Cohen, who, convicted in 1830 of receiving stolen property in Lancaster, was sent to Port Macquarie, a penal colony at the time.
Read more about the history of this dial at: http://www.portnews.com.au/news/local/news/general/sundial-link-to-past/2361551.aspx
Hour Horary Quadrant
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What’s worth more than £150,000? An hour horary quadrant dating to 1396 with the personal seal of Richard II. It is up for auction at Bonham. The quadrant, owned by Christopher Becker in Australia, spent the last twenty years in a bag of pipe fittings. An ancestor of Becker apparently came across the quadrant 150 years ago somewhere in Northern England before its final resting spot in Australia.
This quadrant divides the day into 24 equal hours. With a plumb-line attached to one of its corners, pointing the quadrant towards the sun allows the time to be read at the intersection of the plumb line and one of the engraved scales. On its reverse, the quadrant shows a badge depicting a stag lying down wearing a coronet around its throat, symbols associated with Richard II.
The oldest European astrolabe dated 1326 is credited to being used by Chaucer (1342-1400) and resides in the British Museum.
Washington's Sundial in the Spotlight
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George Washington's Sundial is in the Spotlight: Sometime during 1765-1781 Washington placed a 12 inch brass horizontal sundial at the heart of his Mount Vernon plantation. The sundial sits atop a white painted octagon wood pedestal in the center of the front lawn of his mansion. It stands as a visual reminder of the importance of time to all who passed it. A replica of the original dial now reminds tourists of the time, but the original is in the museum. Go to http://www.georgewashingtonwired.org/ and read more about Mount Vernon and visit NASS_Registry_Dial167 where you can find details of Washington’s dial.Oldest Sundial in the Western Hemisphere
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Where would you look for the oldest dials in the Western Hemisphere? One is attributed to the Pilgrims in Salem in 1620. Earlier slate dials were used by Newfoundland fisherman. But La Fortaleza, in San Juan, the oldest Executive Mansion in the New World may lay claim to the oldest sundial. Sundials in the Antilles.pdf | [ ] | 291 kB |
Sundial Rededication
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A sundial that was originally purchased by the 1910 class of Springfield (Ohio) High School and which adorned the original high school grounds for decades was recently refurbished and rededicated at the new Springfield High School.
Even though the dial adorned the school grounds for much of the 20th century, it eventually found its way into storage, where it remained until it was recently uncovered.
Rare Sundial Sold
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[photo credit: Christie's ]
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A rare stone, polyhedral sundial discovered in England, and thought to date from the Scottish renaissance, sold April 7, 2011 for £16,250 (\(26,500) at Christie's South Kensington, London.
The sundial discovered in 1974, and thought to date from the Scottish renaissance, went on the auction block this April as part of Christie's Travel, Science and Natural History sale in London. The dial is made of stone and technically described as a polyhedral dial, with several independent sundials arranged on different facets of the stone. Pre-auction estimates placed a value somewhere between £7000 and £10,000 (\)11,400 and $16,300) but sold for nearly three times the initial estimate.
Today - Chicagohenge
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The date is Sep. 22, 2022, the date of the fall equinox. Although this is supposed to be the day of equal day and night, we know it's not exactly correct. We measure daytime from sunrise to sunset, measured as the first and last light from the sun peaking over the horizon. When we include sunrise and sunset plus atmospheric refration, at mid latitudes daylight wins by about 10 minutes (not even counting twilight).
 Chicagohenge photo by Tim Hara
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But something magical happens as the sun sets due west on the equinox in Chicago. The sunset direction matches the direction of the Chicago grid of East-West streets. The effect is known as Chicagohenge.
From the Adler Planetarium website (https://www.adlerplanetarium.org/blog/chicagohenge/): "Chicagohenge occurs twice a year and happens when the Sun directly lines up with Chicago’s east-west facing streets ... To fully understand Chicagohenge, you have to be aware of the two main factors that cause it: Chicago’s grid plan and equinoxes...The present-day Chicago grid system can be attributed to the Public Land Survey System -- a surveying method created in 1785 that was used to divide land for selling and settling. But this style of city design has been around since the dawn of civilization and can be found in the ruins of ancient Rome, Greece, and others [sometimes creating solar alignments in these cities such as Manhattan Henge] ... Fun fact: Chicago’s streets line up almost perfectly with the cardinal east and west directions on a compass. This in turn, sets up the perfect stage for Chicagohenge to take place."
The Planetarium Blog continues. "Since the Earth’s axis is tilted, sunlight is not always distributed equally. At any given point, one-half of the Earth is tilted towards the Sun more than the other. As the Earth orbits around the Sun, the part that was tilting away from the Sun begins to be the part that is facing towards the Sun. This is why we have seasons! ... There are two equinoxes each year, one that marks the start of spring (Spring Equinox) and one that marks the end of summer (Autumn Equinox). Thanks to Chicago’s perfectly lined grid system, the bi-annual equinoxes mark a time when the Sun rises and sets directly in line with Chicago’s east and west streets, causing Chicagohenge! ... Finding a place to spot Chicagohenge is a no-brainer! Simply find one of Chicago’s east-west facing streets, plop a seat, and enjoy the view."
Eclipse of Sun by Phobos Seen by Perseverance Rover
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On April 2, 2022 the Perseverance Martian rover's Mastcam-Z camera looked sunward and took a video of the eclipse of the sun by the "potato-shaped" moon Phobos.
According the NASA Mars Exploration Program site, "It’s the most zoomed-in, highest-frame-rate observation of a Phobos solar eclipse ever taken from the Martian surface." NASA reports that "Several Mars rovers have observed Phobos crossing in front of the Sun over the past 18 years. Spirit and Opportunity made the first observations in 2004; Curiosity in 2019 was the first to record video of the event. Each time these eclipses are observed, they allow scientists to measure subtle shifts in Phobos’ orbit over time. The moon’s tidal forces pull on the deep interior crust and mantle of the Red Planet; studying how much Phobos shifts over time reveals something about how resistant the crust and mantle are, and thus what kinds of materials they’re made of."
Watch the video: https://mars.nasa.gov/news/9172/nasas-perseverance-rover-captures-video-of-solar-eclipse-on-mars/
Art Project: "Unit of Measurement"
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The Land Institute is a not for profit organization based in Salina, Kansas, having a goal to create an agriculture system that mimics natural systems in order to produce ample food and reduce or eliminate the negative impacts of industrial agriculture. A mile north of the Institue is their Marty Bender Nature Area where Owen Brown has created an art project "Units of Measurement". According to Jason Beets of the Salina Journal, his project "consists of three sets of sun dials created from praire-colored angled flag poles to symbolically represent the passage of time."
The idea is to meditate on the passage of time. The first set of three poles, called "In the Beginning" is 1,190 feet east of another set of poles called "The Passage of a Second". According to the artiist, this is the distance that the earthrotates in one second. A third site, called "From the Future" is located 723 feet north of "In the Beginning" is placed such that at "... dawn of the summer solstice, the shadows of the sundials at “From the Future” will touch [point to] the sundials at “The Passage of a Second.” Owen said, "I want this installation to make us more aware of where we are, who we are, and how we are ... in relation to the earth, to what we grow, and to what nurtures us."
Interesting art but very poor science. For each cluster of three flag poles, only the one point to North can work as a sundial. And the pole needs to be at an angle from the ground equal to the latitude of 38.855° N. From the photo, the angle is closer to 60°. Fortunately there are no hour lines on the ground to show the incorrect time of the shadow.
Updated Content: 28 Feb 2022
We've recomputed "The Passage of a Second" using Earth Centered Earth Fixed (ECEF) coordinates for the latitude of 38.855° N and an altitude of 1,227 ft attributed to Salinas, KS. The result is an earth radius of 4.973775 x 10^6 meters giving a circumference of 31,251.15km. But to count exactly one revolution of the earth (in inertial space) we need to use the sidereal day of 86164.1 sec rather than the mean solar day of 86400 sec. And just as Owen Brown has separated "In the Beginning" and "The Passage of a Second", the distance is 1190 feet. The angle from east of "From the Future" 723 feet north of "In the Beginning" as seen from "The Passage of a Second" is 31.28° or 121.28° from south. The first rays of the sun appear on the eastern horizon when the center of the sun is actually 0.833° below the horizon. The sun's apparent position is due in part to atmospheric refraction. Taking this effect into account, sunrise on the summer solstice will occur at an azimuth from south of 121.3°, the alignment used by Owen Brown.
Indeed the sunlight is coming from the future on the solstice, travelling the Pathagorean distance of 1,392.4 feet in (424.4m) between Future and Passage requires 1.4 microsecond. Owen Brown's simple constructs with precision placement is something to be contimplated.
Read more at: http://www.salina.com/news/20181027/land-institute-art-project-reflects-on-time-nature