What's New Under The Sun
VSSC Space Museum gets Polar Sundial
Tuesday, 17 December 2024 23:47In November 2024, a team consisting of members from SPL, TTDG and CMD of VSSC successfully designed and installed an accurate and fully functional sundial at the Rocket Garden of VSSC Space Museum, Thumba (8.53°N, 76.86°E). Following a space theme, the vertical gnomon is a 3-stage rocket that casts its daily and seasonal shadow on a dial face 1 1/2 meters by 1 meter. The the sundial face...
Historic Sundials of Andalusia
Saturday, 16 November 2024 00:07Esteban Martínez Almirón has published a new book Historical Sundials: Forgotten Andalusian Treasures (Relojes de Sol Históricos Tesoros Andaluces Olvidados) In it he reviews over 400 sundials from the Andalucian region of southern Spain Originally to celebrate the 25th year of the website https://relojandalusi.org/ Esteban Martínez Almirón began showing his sundial drawings on the site....
Shelbyville Sundial
Wednesday, 13 November 2024 19:36It isn't often that a sundial face is created before the gnomon is attached. In Shelbyville IN a large, circular art piece in the form of a sundial, was created at the Blue River Trailhead early in 2024. If they had chosen an analemmatic sundial, a walker of the trail could have simply stood on the appropriate date and used his or her own shadow to tell the local solar time. ...
Sun Tower Competed
Monday, 04 November 2024 18:38The Sun Tower's shadow marks the passing of the seasons credit Jonathan Leijonhufvud For two years News Atlas (https://newatlas.com/architecture/) has reported on the progress of the construction of the Sun Tower in Yantai, China. The 164-foot (50m) curved conical tower was designed by OPEN Architecture symbolized the watch towers of the Ming dynasty (1368 to 1644 CE)...
Hamilton Dial Restoration
Monday, 04 November 2024 17:30NASS Registered Sundial #1109 at https://sundials.org/index.php/sundial-registry/onedial/1109 is one of a series of bronze sundials presented by Daughters of Union Veterans of the Civil War, dedicated to the memory of the Grand Army of the Republic. Unfortunately the dial in Hamilton, Ohio, suffers from neglect and the gnomon has long been missing. With support, this dial has been designated...
Canadian Sundial Coin
Thursday, 10 October 2024 17:56Photo of the Canadian $20 Silver Coin with the reverse as a Sundial. Photo courtesy of the Royal Canadian Mint. Sundial design by Anna Bucciarelli. The Canadian Royal Mint will release a fully functioning sundial coin expected to ship on 12 December, 2024. The obverse is a profile of His Majesty, Charles III (designed by Steve Rosati) and the reverse is a...
NASS Sundial Class
Monday, 07 October 2024 03:03Once again NASS presents Elements of Dialing, a twelve week course covering the basics of sundials, led by Steve Lelievre. The course covers basic principles of how sundials work, calculations involved in designing sundials, types of time (systems of time measurement), and some of the history of sundials.The course is intended for people who are new to sundialing and who wish to learn some of...
Ancient Egyptian Clock
Tuesday, 24 September 2024 16:47Dario Radley reports in Archaelogical News Online Magazine (Aug 24, 2024) that an ancient observatory from the 6th century BCE was found by the Egyptian Supreme Council of Antiquities at Tell El-Fara'in archaeological site. “It highlights the advanced astronomical knowledge of the ancient Egyptians, including their ability to determine the solar calendar and significant religious and...
Getty Research Institute on the Solstice
Saturday, 22 June 2024 19:38Off Interstate 405 in the hills of Los Angeles is the Getty Research Institute, part of the campus of The Getty Center. The Center houses the free Getty Museum, the Getty Library, Getty Research Institute, Getty Foundation, and Getty Conservation Institute. The Getty Research Institute opened its doors to the public in December of 1997, where besides the thousands of books, art collections,...
Preparing for the Solar Eclipse of April 8th 2024
Sunday, 24 March 2024 18:30There 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...
Seiko Designs Equatorial Sundial Watch
Sunday, 24 March 2024 01:42When 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...
Rare Astrolabe Discovered by Chance in Verona Museum
Wednesday, 06 March 2024 00:17Dr. 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...
September 11th Remembrance
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September 11th is a time of remembrance. At Freedom High School in Woodbridge, Virginia stands a large sundial dedicated in 2004 with four inlaid plaques. The plaques are arranged on the ground such that the gnomon shadow tip falls on them at 8:45, 9:03, 9:37 and 10:07 AM, the times of the four air crashes. Near the sundial is a low, black granite panel commemorating the citizens of Prince William County that lost their lives on September 11th, and the names of those citizen are on bricks surrounding the sundial.
Two Worlds - One Beginning
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Everyone is excited about the landing of Perseverance, the Mars rover. If you look closely at the first panorama of the Martian landscape you will see on the equipment bay of Perseverance the Mastcam color calibration target. It sort of looks like it could be a sundial. In 2004 a similar calibration target was used as the first Martian sundial, designed by Dr. Woody Sullivan and Jim Bell with the support of The Planetary Society and Bill Nye, "The Science Guy" [See PDF at bottom]. Is the Mastcam color calibration target a sundial as well? Here is Dr. Sullivan's answer to a group of sundial enthusiasts (2/25/2021):
"The short answer is “No”. The longer answer follows. The new object on Perseverance (officially the "photometry calibration target") has obvious similarities to the Mars dials on Spirit and Opportunity that landed in 2004, and in fact it is a technological and aesthetic “grand-daughter” 17 years later. (The intervening generation is the Curiosity rover, which landed in 2013 and is still alive). The Mars dials that a small group of us designed and fabricated and then occasionally “used” to read Martian time were a great experience for me.
"But after over a decade of Spirit and Opportunity, I decided not to get involved in any future NASA missions — they gobble up a lot of time! The science and fabrication of the new calibration target (as for Curiosity) is led by a group at U. of Copenhagen.
"Nobody has ever done anything with the orientation of the shadows cast by the “gnomon” on Curiosity and I’m sure nobody will for Perseverance either. By the way, independent of gnomonics, the vertical tube has a vital scientific purpose: its shadow on the gray and colored patches allows one to calibrate camera images properly in shadow as well as sunlight.
"The various symbolism and messages on Perseverance also stem directly as heritage from Spirit and Opportunity . You can find a tremendous amount of detail about all aspects of the Perseverance cal target (including construction) at https://mastcamz.asu.edu/mars-in-full-color/ [See PDF at bottom]. The feature I like best is the motto “Two Worlds, One Beginning”, which nicely refers to Spirit and Opportunity ’s “Two Worlds, One Sun” as well as early solar system history and the possibility of early life on Mars. (Curiosity has the terrible motto “To Mars to Explore”.)
"Nevertheless, I watch the procession of missions with great astrobiology interest. And someday I will write up the whole Mars dial experience, including many Martian landscape images in which it appears, and how a student and I were actually able, using its shadow, to measure the Martian analemma at local mean (“clock”) noon over a Martian year ( = 1.9 Earth years).
— Woody Sullivan
Prof. (Emeritus) Woodruff T. Sullivan, III
Dept. of Astronomy & Astrobiology Program Box 351580
University of Washington
Seattle, WA 98195 USA
Planetary Society Brings Back Earth Dial
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The Planetary Society and Bill Nye, The Science Guy, are bringing back the Earth Dial, which is a simple to make gnomonic horizontal sundial reminiscent of the sundial incorporated into the Mars rovers Spirit, Opportunity and now Curiosity. Their original and fundamental purpose is to serve as test patterns for the rover cameras, but they also provide an opportunity as unique shadow casting sundials.
“Since we had shadows being cast on Mars, I suggested it be a sundial… I admit I was quite enthusiastic about it. Steve Squyres, the Principle Investigator on the Spirit and Opportunity missions, made the call, and the Mars Dials were created. He received the [Planetary] Society’s Cosmos medal a few years ago, for his wonderful leadership of the project.”
The Earth Dial project was started in 2004 and now, nearly a decade later, is being brought back. Visit the Planetary Society website Planetary Society - Earth Dial for details and download the attachment below to construct your own Earth Dial.
TED Lecture - Sundials to Mars
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Bill Nye, The Science Guy gives a 7 minute TED-ED talk describing the excitement of creating sundials on Mars. http://ed.ted.com/lessons/sending-a-sundial-to-mars-bill-nye
TED stands for Technology, Entertainment, and Design, a nonprofit organization devoted to spreading ideas of worth. Conferences are held each year with more than 50 guest speakers to motivate the audience on many different fields and now through YouTube, you can share the excitement of sundialing.
Curiosity Carries Sundial
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With the successful landing of the NASA rover Curiosity, another sundial is on planet Mars. Turning the color calibration target into a sundial was the idea of Bill Nye, the Science Guy, and Professor Woodruff Sullivan at the University of Washington, originally hailed by “Two Worlds – One Sun”
THese two sundial enthusiasits have been encouraging people around the world to make their own sundials and collectively participate using webcams to tell solar time around the earth. See: http://sundials.org/index.php/features/168-curiosity-sundial-launched and read the details of the sundial with the following PDF download: MarsDialReport.pdf
Curiosity’s calibration target was created by Tyler Nordgren at the University of Redlands. However Nordgren and a group of six scientists, astronomers, educators, and artists (including Nye and Sullivan) went further. Said Nordgren, "But we thought, why not use this very dry boring technical piece of equipment, and turn it into something beautiful and evocative?"
The calibration target turned sundial is actually a leftover from NASA’s Mars Exploration Rover (MER) Spirit. Along the edges of the sundial MARS is written out in 16 different languages. The sundial’s center represents the sun with a concentric grey ring for the earth’s nearly circular orbit and a displaced white ring for Mars eccentric orbit. The positions of Earth and Mars, shown respectively by a blue and red dot are placed for the date of impact at 10:32 pm Aug 5th PDT. Every MARS sundial has a date and motto. “It's sundial tradition,” says Nordgren. Curiosity says "MARS 2012" and "TO MARS TO EXPLORE."
Each home-plate color slice has a phrase describing what the mission means for human exploration. It reads:
“For millennia, Mars has stimulated our imaginations. First we saw Mars as a wandering red star, a bringer of war from the abode of the gods. In recent centuries, the planet's changing appearance in telescopes caused us to think that Mars had a climate like the Earth's. Our first space age views revealed only a cratered, Moon-like world, but later missions showed that Mars once had abundant liquid water. Through it all, we have wondered: Has there been life on Mars? To those taking the next steps to find out, we wish a safe journey and the joy of discovery."
Dr. Woody Sullivan discussed the history of the Mars Dials on a recent Sundial Digest forum (11 Aug 2012, Vol. 80, Issue 8) https://lists.uni-koeln.de/mailman/listinfo/sundial
“[Above] is the first image of the latest "Mars Dial", which indeed is the calibration device for the main camera ("Mastcam") on Curiosity Rover, which landed safely in Gale Crater on Mars 5 days ago (hurrah!)."
"The Mars Dials were originally fabricated in 1999 for the Mars Rovers Spirit and Opportunity, which landed in 2004, and the latter of which is STILL working over 8 years later. To date over 35,000 images have been taken of the two Mars Dials - the most photographed thing on Mars! As mentioned below, I was intimately involved in all aspects of making these calibration devices into working sundials - design, fabrication, operations, etc. However, because of other commitments I chose not to be part of any Curiosity efforts, so my report in the following paragraph is that of a (very) interested observer."
"In order to save some money, the Curiosity Mars Dial is a slight modification of one of the 6 copies that we made in 1999. A couple of magnets were added (to try to repel dust), new plates were put on it to change various wording such as the date and, in particular, the motto. The motto is now "To Mars To Explore" rather than the previous "Two Worlds One Sun". But the biggest difference is that, as far as I know, no one is ever going to superimpose the hour/date lines so that it can actually be used as a sundial! And yet NASA's publicity continues to call it a sundial.....But I'm still very happy to see the first images of it….”
The image here is from the Mars Exploration Rover Spirit (look carefully for the motto “Two Worlds One Sun”) and according to a NASA news release, “was processed by students in the Red Rover Goes to Mars program to impose hour markings on the face of the dial. The position of the shadow of the sundial's post within the markings indicates the time of day and the season, which in this image is 12:17 p.m. local solar time, late summer. A team of 16 students from 12 countries were selected by the Planetary Society to participate in this program. This image was taken on Mars by the rover's panoramic camera.” [Image was produced at Cornell University - Image Nr: PIA05017]
For more details of the Curiosity sundial, read an interview with Tyler Nordgren: http://www.popsci.com/science/article/2012-08/mars-rover-curiosity and http://wtvr.com/2012/08/03/nasa-mars-rover-curiosity-will-land-early-monday/
Read more about Curiosity’s instruments at http://www.nasa.gov/mission_pages/mars/main/index.html
Curiosity Sundial Launched
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[photo courtesy of NASA]
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The spacecraft was launched toward Mars on 26 Nov 2011. Onboard Curiosity the camera calibration sundial has four edges each containing a panel of text and image, written by Jim Bell, planetary scientist from Arizona State University and the Mars Exploration Rover team with graphics designed by artist Jon Lomberg.
The digital camera and calibration target was created by Tyler Nordgren from the University of Redlands and a group of six scientists, astronomers, educators and artists worked together to create a digital camera that is calibrated to photograph the climate on Mars. On the team was Bill Nye and Professor Sullivan.
Dr. Bell now executive Director of the Planetary Society and Lomberg were both on the team that designed the similar sundials for the the Spirit and Opportunity Martian rovers. Artist Jon Lomberg has a long history in spacecraft graphics, starting with Design Director for NASA’s Voyager Golden Record and a long-time collaborator of Carl Sagan. He won an Emmy Award for his work as Chief Artist of the TV series COSMOS. Read more at http://www.redlandsdailyfacts.com/news/ci_19476230 and http://citizenofthegalaxy.com/wordpress/?p=169
ENEA Solar Compass Soon to be Smartphone App
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The National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA) is an Italian Government sponsored research and development agency. In 2017 Sara Bollanti and her team at ENEA in Frascati developed a solar compass that "is 100 times more precise than magnetic compasses..." with applications for surveying, civil engineering, and for us, sundial alignment. The heart of the device is a combination of GPS receiver for determining both time and geographic position and a solar collector consisting of a narrow slit and a CMOS image detector. Essentially this is an electronic solar azimuth compass. A smallArduino computer uses the UTC time plus geographic coordinates to compute the local sun azimuth and then compares it to the position of the sun's projection of a slit on a CMOS detector. According to ENEA, the "...electronic solar compass is compact, completely automatic, cheap, and reaches an accuracy better than 1 arcmin. The latter is one of the best currently available values, comparable to those achievable by means of much more expensive and sophisticated devices, like coupled GPS systems (see for example U.S. patent 5,617,317A, 1997) or gyrocompasses. Furthermore, the ENEA compass provides the orientation in a few seconds, a time extremely shorter than that necessary for gyrocompasses."
By 2018 this was tested in Antarctica and now the mathematics has been reduced to fit into your smart phone. In April 2020 the ENEA team announced the developed the smartphone app i called "SunPass". It is currently in beta testing and will soon be available at the Play Store. In basic form, the app allows you to acquire the sun azimuth by pointing toward the shadow of a vertical object such as a building ("shadow method") or the shadow of a vertical pole ("gnomon method"). A more accurate appraoch is to construct a box with a slit on the front and hole on top such that the smartphone can observe the illuminated sun line on the floor of the box ("Slit method"). For the advanced, one can construct a precision holder from a kit that mounts on a tripod.
ENEA's goal of a low cost, simple method of precision alignment is now accessible to all. This new technology implements the mathematics of determining the sun's azimuth in elegant ways. But of course it only works on sunny days.
Read more at:
http://eai.enea.it/archivio/anno-2017/astana-italy/the-enea-solar-compass-how-to-catch-more-sun-by-using-the-sun
And watch the video:
https://www.spiedigitallibrary.org/conference-proceedings-of-spie/11352/1135216/Accurate-and-low-cost-ENEA-solar-compass-for-precision-metrology/10.1117/12.2555747.full?SSO=1
Daku's Shadow Writing
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Whether it be Delhi or Las Vegas, artist Daku brings shadows to life, creating words that slowing change their shape but never lose their meaning through the course of the day. As reported by mymodernmet.com, "As part of the St.Art festival, which curates public art in Delhi’s Lodhi district, Daku’s carefully realized [shadow] installation demonstrates the power of words. The artist, whose name means 'bandit' in Hindi, had been thinking about executing this project for several years when finally given the opportunity by the festival." The anonymous artist Daku told CNN, “I had to decide the size of the letters, the length of the pieces, and the angle I could place them in so pedestrians could easily see it.” mymodernmet.com concluded "The artist carefully selected which words to include—balance, order, reflection, future, seasons, space—each a reflection on movement, time, and change. Reaching its apex at mid-day, the letters slowly blur and dissolve, put to rest each evening before beginning anew."
The making of shadow writing in Las Vegas by Daku
Daku's cut-out words on the south facing walls of buildings is a clever implementation of sundial and involves a lot of subtle mathematics. Daku's lettering is placed on the wall horizontal to the ground, usually with very little change in the scale of the lettering. Mathematically the noonday lettering on the wall is lengthened by the tangent of the latitude plus solar declination. But the visible size of the lettering is foreshortened by the cosine of the upward look angle of the pedestrian on the ground.
Read more at: Daku's installation in Las Vegas and Daku's installation in Delhi
Digital Prescription
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As reported in the ArchDaily.com website on 23April 2016 by Patric Lynch, the design group Prescription in conjunction with Arup have developed a sophisticated sundial based on the analemmic path that the sun travels throughout the year. The classic "8" shaped analemma is made into a cone (think of someone stepping on an ice cream cone) and repeated with esthetic cutting of the cone top for each hour. At the bottom of the cone is a stenciled hour number and the angle of the analemmic cone only allows sunlight to poke through the stencil for the appointed hour.
The original prototype of this dial was made of flexible plastic through a 3D printing process. Prescription believes that "...the design is 100% scalable; the designers foresee applications for the design in both park and festival pavilions and home installations..."
A video of this analemmic sundial by Grisha Zotov can be seen at https://vimeo.com/161675472
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