What's New Under The Sun
Trio of Solar Eclipses in Spain
Thursday, 28 May 2026 22:31
A wonderful trio of solar eclipses on the Iberian Peninsula will occur. The first will occur on 12 August 2026 with viewing time of more than 2 minutes. lThe second, almost exactly a year later on 2 August 2027, will be even more spectacular, with an eclipse duration of 4 minutes. On 26 January 2028 Spain will encounter an annular solar eclipse, creating a view of the rim of the sun...
Clark College Celebrates Sundial at 40th Anniversary
Thursday, 07 May 2026 20:28
In August, 2009 the NASS Conference was held in Portland, Oregon and visited the sundial at Clark College in Vancouver, WA. The equatorial sundial, built in 1984, had just received a new gnomon: an analemmatic or "bowling pin" gnomon that corrects for the Equation of Time. On May 4th, 2026 the local newspaper of Clark County, the Columbian, reported that more than 40 years after its...
1720 American-Made Brass Sundial up for Auction
Tuesday, 21 April 2026 16:47
Heritage Auctions of Dallas, Texas, is auctioning a brass dial signed by "Patrick Hepburn, Marlborough, Maryland, 1720".. The dial face has a rich green patina with rough but accurate engraving of Roman numeral hours, delineated with half, quarter and eighth hour marks. The dial has an eight point compass rose with lettered points. Latitude is engraved as "LATT 39".The wide, but...
New Sundial Glossary of Terms
Sunday, 12 April 2026 21:30
Do you wonder what a Bifilar Sundial is? Or a Campbell-Stokes Recorder? Maybe you are studying facts about astrolabes and come across the word almucantar. Are they rings in the sky?
Our perhaps you want to make a vertical dial and need the trigonometric formula to draw the hour lines and have forgotten where to look. All of these questions can be answered plus internet and NASS...
British Columbia goes on Permanent Daylight Time - 2026
Monday, 06 April 2026 01:08
The Times Colonist in an article of March 28, 2026 by Hannah Link, reports that as of November 2026, British Columbia will change to permanent daylight time. "That means sundials in B.C. will always be one hour behind, no matter the time of year, said Victoria-based sundial enthusiast Steve Lelievre."
Photo: Times Colonist - The sun shines on the Sundial Garden in Beacon Hill...
World Sundial Day - UPDATE April 2026
Monday, 09 March 2026 15:10
Building on the success of the 2025 inaugural event celebrating world sundial day on March 20th, 2026. This global online gathering celebrates sundials, timekeeping, astronomy, history, art, mathematics, craftsmanship, and cultural heritage across the world.
World Sundial Day was originally created by Esteban Martínez Almirón on his website Reloj Andalusí. World Sundial Day is celebrated...
NASS Conference Coming to Louisville, KY - June 25-28, 2026
Thursday, 22 January 2026 18:30
UPDATE: We will have a special tour of the Kentucky Viet Nam Memorial Sundial. See the attachment about the construction of this wonderful memorial.
Get ready to travel. This year the 31th NASS annual conference will be held in Louisville, KY at the Hyatt Regency Hotel June 25th - June 28th. The conference starts Thursday June 25th at 4:30pm with an opening reception, introductions,...
Madison Historic Dial Returns
Monday, 13 October 2025 22:49
On October 4, 2025 Madison Historical Society of Ohio was able to have their sundial returned after 32 years, when in 1993 it was moved to the lawn of Lake County Courthouse to reduce the chance of vandalism. The sundial was originally placed at Madison Home 100 years ago on Saturday, October 24, 1925 during a conference of the Women's Relief Society. From 1904 to 1962 the state ran this...
Elements of Dialing Course - 2025
Monday, 15 September 2025 19:42
NASS is pleased to announce the upcoming fifth instance of Elements of Dialing, our introductory course about sundials, their history, and the science that makes them work. The free 12-lesson course, intended for those are new to sundialing, runs from 27 October 2025 until 26 April 2026. The course instructor is Robert Kellogg, NASS Vice President and Sundial Registrar. Bob will be...
Sun Queen of World War II
Thursday, 11 September 2025 23:11
A Hungarian born American scientist, Mária Telkes (1900-1995), was called "The Sun Queen" and among other honors, was postmousthly inducted into the National Inventors Hall of Fame. She lived to 95 and for most of her life developed solar power in a variety of forms.
Trained as a biophysicist, she worked for Westinghouse Electrical and Manufacturing Company in Pittsburgh, PA, where she...
2025 Conference -Ottawa
Thursday, 28 August 2025 23:25
The annual NASS Conference was held 7-10 August, 2025 in Ottawa. As usual, the conference began late Thursday afternoon with an introduction social and a "grab bag give away", taking your chances with tickets to win the bag's prize. Will Grant was the final winner of the Walton Double Planar Polar Sundial, but Paul Ulbrich beat the statistic odds and won this prize three times,...
Prosciutto di Portici Sundial's Owner
Tuesday, 10 June 2025 18:51
Prosciutto di Portici (Ham) Sundial
Photo: Getty Images
The Prosciutto di Portici Sundial, more often called the Portici Ham Sundial, dates from the first century somewhere between 8 BCE to 79 CE. This small silvered bronze dial was uncovered on 11 June, 1755 in the ruins of Herculaneum (current day Portici) in the "Villa of the Papyri", buried in...
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, traveling the Pythagorean 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 contemplated.
Read more at: http://www.salina.com/news/20181027/land-institute-art-project-reflects-on-time-nature
Cosmic Room on the Equinox - 2018
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The heart of the Cosmic Room is an unusual vertical meridian sundial created by sunlight passing through a slot on the roof above. In winter the solar meridian transit is labeled with a column of blue tiles and at the spring equinox the tiles change to orange. The sign "Analemma 12:45" indicates civil time on the spring equinox when the sun is on the local meridian. With the sun overhead, the beam of light follows the vertical set of tiles downward until it reaches the boundary between orange and blue tiles - the equinox has arrived. Ruben Nohitol has been photographing this event for the last 16 years, every year since 2002. From a ceiling hole Ruben marks the image of the sun at 12:45 on the floor with a small green circle. He does this on dates throughout the year(s), not only creating a nice analemma, but does it with such precision that he is able to notice the slight shifts in solar equinox position through the leap year cycle of four years.

More impressive is the due west sunset on the equinox. A beam of light streams though a hole in the western wall of his hacienda, across the living room, through a square hole between rooms, across the Cosmic Room grazing past the vertical sundial and its tiles, and lands as a bright solar disk at the far end of the Cosmic Room on a vertical wood screen mounted on an exit doorway. To add to the drama of the setting equinox sun, Ruben placed a model of the pyramid of El Cerrito on a shelf in the Cosmic Room blocking some of the sun's rays. The result is a shadow of the the pyramid against the solar disk, giving the illusion of thesun setting over the great pyramid. You can see his vertical meridian and more at http://www.makeaholeinthewall.com and the sundial in operation at http://www.sundials.org/index.php/dial-links/videos/meridiane See his patience to photograph the real setting sun over the pyramid of El Cerrito in Queretaro, Mexico at http://www.sundials.org/index.php/dial-links/videos/analemmas-time-and-motion
Cosmic Room with Solar Analemma
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[photo courtesy of Ruben Nohuitol]
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Ruben Nohuitol of Queretaro, Mexico has a unique solarium or “cosmic room” to observe the rays of the sun throughout the year. He has patiently constructed a wonderful time-lapse video following the sun every day at 12:45 pm. His construction has a vertical meridiana beam of light descending and then ascending the wall as time passes throughout the year. A second sky-light gnomon creates a classical analemma on the floor.
Trio of Solar Eclipses in Spain
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A wonderful trio of solar eclipses on the Iberian Peninsula will occur. The first will occur on 12 August 2026 with viewing time of more than 2 minutes. lThe second, almost exactly a year later on 2 August 2027, will be even more spectacular, with an eclipse duration of 4 minutes. On 26 January 2028 Spain will encounter an annular solar eclipse, creating a view of the rim of the sun against the lunar silhouette that many call “The Ring of Fire”.
The eclipse expert of Fred Espenak lives on in spirit. From Manuel Pizarro, an NASS member, comes a unique map of the umbral and penumbral events of these three solar eclipses. He has created an app using the Google Earth Engine (GEE).
The app is based on "the rigorous astronomical algorithms of Jean Meeus and uses Besselian elements provided by NASA. All the geometric computational load—from the calculation of the shadow's path to the generation of the umbra and penumbra— was processed in real time on Google's servers, allowing for a smooth experience without overloading the user's device.To ensure its international reach, the interface is completely translated into Spanish, English, French, and Italian."
Visit: https://gee-astrolab.users.earthengine.app/view/solar-eclipse The App features and detailed instructions can be downloaded at the bottom of this article.
Another important website mapping the eclipse is from the Instituto Geográfico Nacional: https://visualizadores.ign.en/eclipses/2026 (english)
This site of The Trio of Eclipses also includes a detailed and controllable topographical map of Spain that can be switched between the languages in Catalan, Basque, Galacian, Spanish and English.
Detailed eclipse information, including predicted weather can be found at https://eclipsophile.com/tse2026/
Don’t forget to wear your solar protective glasses until total eclipse begins, otherwise you can permanently damage your eyes.
British Columbia goes on Permanent Daylight Time - 2026
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The Times Colonist in an article of March 28, 2026 by Hannah Link, reports that as of November 2026, British Columbia will change to permanent daylight time. "That means sundials in B.C. will always be one hour behind, no matter the time of year, said Victoria-based sundial enthusiast Steve Lelievre."
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Photo: Times Colonist - The sun shines on the Sundial Garden in Beacon Hill Park. The circular garden features a bronze and stone sundial created in 1947 by the Royal Astronomical Society of Canada. Situated in the Rose Garden area, it displays solar time, with an inscription reading “I count only the sunny hours.” DARREN STONE, TIMES COLONIST |
From Ogden Point to Greater Victoria Harbour to the vertical dial at Christ Church Cathedral, sundials will be an hour off. "The sundial was installed at the [cathedral] in 2001 during renovations and is dedicated to the memory of Betty Whitlow, the wife of Rev. Brian Whitlow, who was dean of the cathedral from 1955 to 1980."
Links continued in an interview with Steve Lelievre, "...he became fascinated with the Earth’s movement around the sun while gardening with a friend back home in the United Kingdom. The friend wanted to choose the right plants based on the sunniest areas of his yard, so he poked a stick in the ground and watched its shadow move. 'I was completely amazed by that and had to go away and figure out for myself how that could be,' he said. 'Once I got interested in that celestial mechanical stuff, I got interested in sundials. It’s kind of a natural progression.' "
Links also interviewed Vernon Miles is the great-great-nephew of William Willet, the English inventor of daylight time. "The 83-year-old learned about Willett and his invention as a child, and for most of his life, it’s been a fact he uses to poke fun at his friends when they complain about having to change their clocks....Miles said he would have preferred that B.C. move to permanent standard time instead of daylight time. 'I chuckled to myself,' he said. 'My uncle will forever turn over in his grave.' "
Read the full article at: https://www.timescolonist.com/local-news/will-sundials-be-adjusted-for-year-round-daylight-savings-only-time-will-tell-12066472
The transition to permanent DST actually began Sunday, March 8, 2026 according to the B.C. government. Now there is no turning back the clock on November 1st. Under the Interpretation Amendment Act, B.C. government adopted permanent year round daylight saving time (DST) "to improve people's overall health, reduce disruptions for families, simplify scheduling and provide an extra hour of evening light during the winter months." Certain locales have exceptions such as "People in southeastern B.C. (East Kootenay and Golden region) currently switch between mountain standard time and mountain daylight time, in line with Alberta."
See: https://www2.gov.bc.ca/gov/content/governments/celebrating-british-columbia/daylight-saving-time for a complete description of the conversion to permanent daylight saving time for British Columbia.
Pros and Cons of Daylight Savings Time
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In a 24 March 2025 article from the on-line Science Advisor (American Association for the Advancement of Science) Phie Jacobs summarizes the "great debate" of the yearly shift from standard time to daylight savings time. In January 2025 the US Senate introduced the Sunshine Protection Act to permanently have daylight savings time year round. Certainly 54% of Americans do not like the annual migration from standard to savings time and back. In the US, daylight savings time was instituted in 1918 during World War I.
"José María Martín-Olalla, a physicist at the University of Seville and lead author of the new position paper, argues that seasonal clock changes also represent a practical solution to a broader problem: reconciling the fixed, clock-driven schedule of modern life with sunrise times that vary throughout the year."
Jacobs points out that numerous studies have linked time-related sleep disruptions to increases in heart attacks, strokes, traffic accidents, and workplace injuries, and sleep researchers strongly oppose that idea on the basis that extra-dark mornings and extra-bright evenings would dangerously disrupt people’s sleep. Many medical and scientific organizations instead advocate for permanent standard time.
Jacobs sees a middle point, saying that according to Fong-Isariyawongse, human biology functions according to light exposure and people’s circadian rhythms already naturally adjust throughout the year. “Instead of manipulating clocks,” she says, “a better approach would be to allow workplaces and schools more flexibility in adapting schedules based on natural light conditions.”
There is no easy solution. Maybe the middle ages had it right using unequal time.
Read the full article at: https://www.science.org/content/article/scientists-weigh-pros-and-cons-daylight-saving-time
Photo credit: Timothy A. Clary/AFP via Getty Images
Moon Time Using an Analemmatic Sundial
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![]() By the Light of the Moon
Photo by Dr. Jeff Kretsch
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The analemmatic (human) sundial at Turner Farm Observatory Park in Great Falls, VA made by Eagle Scout candidate Kenny Dieffenderfer and Troop 1547 marked a unique place in sundialing history this July 23rd. The Analemma Society sponsors free Friday night public viewing of the heavens through telescopes at Turner Farm's Roll-Top Observatory. But just outside the Observatory on the sidewalk is Kenny's analemmatic dial. Could this dial tell correct time by the light of the moon?
On July 23rd this question was put to the test. It was almost exactly a full moon and the sky was clear. As can be seen in the accompanying photo taken by Dr. Jeff Kretsch at approximately 10:10pm EDT, the lunar shadow of a volunteer human gnomon cast a shadow of about 9:10pm standard moon civil time. How did this come about?
The important facts needed to make the analemmatic dial tell the correct "moon time" is knowing both the phase of the moon and the declination of the moon. On that night the moon was very close to being exactly a full moon and the declination of the moon was 25 degrees south of the equator. The maximum that the sun ever gets is 23.45 degrees south of the equator at the winter solstice. That means that (with practical precision) even though it was a late July night, the human gnomon must stand on the dial's zodiac walkway at the Dec-Jan winter solstice mark.
If this were the sun, we apply a plus 8 minute correction for the 77 deg west longitude of the observatory. The moon gets the same treatment. But what about the moon's phase and the "equation of time"? Here we find a fortunate coincidence: The moon was full moon at 10:37pm EDT on that Friday night, so by luck the moon was almost exactly opposite the sun. The moon's average full moon to full moon (a synodic month) is 29.53 days. Thus the average moon's lead or lag of a mythical full moon is about 49 minutes per day. Therefore the lunar phase correction is approximately 49 x 20/1440 = 0.68 minutes (41 seconds) ahead of the average full moon. Finally the sun's EOT for Friday July 23rd is approximately 6min 30 sec to be added to a dial's shadow to get civil time. But the moon opposite the sun has EOT in the opposite direction of minus 6min 30 sec. The net lunar correction is therefore +8.0 -.68 -6.5 = 50 sec, just less than one minute that needs to be added to that night's observation analemmatic shadow. One might say that the moon and sun were in perfect alignment!
Celebrate the Spring Equinox From Your Home-2020
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Here in Great Falls Virginia on the day of the Spring Equinox, March 19th, it's a rainy day. Perhaps that helps us want to stay inside with all of the travel and meetings restrictions imposed because of the Covid-19 virus. However, astronomical events aren't deferred because of human and biological issues. Late today the sun crosses the celestial equator and heralds in Spring. You can observe this event remotely thanks to Lowell Observatory in Arizona. Lowell Observatory will begin Live Streaming the event starting at 9pm EDT. "The spring equinox in 2020 occurs on Thursday, March 19 at 8:49pm MST/PDT (3:49am GMT), when the Earth's axis is exactly perpendicular to an imaginary line drawn between the Earth and Sun. On the equinox, the Sun rises due east, and it sets due west, no matter where you are on the Earth."
https://www.youtube.com/watch?v=LqP1Md85HHs&feature=youtu.be
2018 Sundial Calendar
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Dan-George Uza has prepared a calendar for 2018 "containing images of Romanian sundials and some daily astronomical information (the equation of time, the Sun's declination angle & zodiac sign, the Moon's phase & age etc.).... The calendar reflects the usual Romanian practice of starting weeks on Mondays, being the first working day, although orthodox religious calendars have reverted to starting weeks on Sundays due to religious reasons since 2011. The days of the week have been translated to their English counterparts for your convenience. Apart from the last two, which have different etymological background, they all closely follow the names of the ancient planets" Luni - Luna (Moon), Marti - Marţe (Mars), Miercuri - Mercury (Mercury), Joi - Joe/Jupiter (Jujpiter), Vineri - Venus (Venus) Sámbătă - from the Latin sa(m)bbatum meaning Sabbath, Duminica - from the Latin (dies) Dominica meaning day of the Lord. .... You may download the English version at the link below:"
https://goo.gl/FNafub
Dan explains that the calendar " includes a brief introduction to the Romanian calendar, such as an explanation for the names of the days and months, the dates of national holidays etc. This is actually my second calendar. I did the first one last year inspired by Fabio Savian's French Republican Calendar. A big thanks goes to Patrick Powers who was kind enough to correct my spelling mistakes for this English edition."
"The astronomical data was generated in Sun Ephemeris, Gian Casalegno's excellent software. The calendar is freeware so you may of course share it. It's intended for A3++ size paper (330x483mm) but I guess simple A3 will do."
"Have a Happy New Year or - as we like to say in Romanian - La Multi Ani!"
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