Wednesday, August 22, 2018

Are Sundials, to Tell Time, Really Obsolete ?

                    http://buhlplanetarium2.tripod.com/sundial/carnpa/libpk/pix/lsw/sundial26lsw.jpg   
Photograph of an Open Armillary Sundial (which tells both time and date) located at the northern tip of Library Park, near the center of the Pittsburgh suburb of Carnegie, Pennsylvania; at the top of Library Hill is the historic Andrew Carnegie Free Library and Music Hall, the fourth (of only five) Carnegie libraries both built and endowed by industrialist and philanthropist Andrew Carnegie. This was the first of several Pittsburgh-area sundials visited by the North American Sundial Society on August 17, during their annual conference.
(Image Source: Friends of the Zeiss; Photographer: Pittsburgh-Area Free-Lance Photographer Lynne S. Walsh)

By Glenn A. Walsh
Reporting for SpaceWatchtower

Today, with computers, smart-phones, and atomic clocks, are sundials, for telling time, really obsolete? For a dedicated group of amateur scientists, members of the North American Sundial Society, the answer to this question is an emphatic no! In fact, they are using computers and high technology to design and create even better sundials!

This-past weekend (August 16 to 19), the North American Sundial Society held their annual conference in the Oakland Civic Center District of Pittsburgh. The conference included many sessions on new types of sundials and new ways to design and use sundials, in addition to spending a day visiting several local and historic sundials in the Pittsburgh area.

Several of the sessions were presented by Fred Sawyer, whose breadth of knowledge of all aspects of telling time by sundial is amazing. He is President of the North American Sundial Society (NASS) and co-founded the educational organization in the Autumn of 1993. Mr. Sawyer, who now lives in Connecticut, received Masters Degrees in History and the Philosophy of Science from the University of Pittsburgh in 1976.

Mr. Sawyer's presentations ranged from determining the mathematical scales for laying-out a horizontal sundial to a session on how to create a sundial that tells time by the light of the Moon! Mr. Sawyer, and NASS member Frank King, both made presentations regarding Ring Sundials, smaller portable sundials that one can carry with them or wear.

“3D Printing A Double Helix Sundial” was the title of a presentation delivered by NASS member Bob Kellogg. According to Mr. Kellogg, it takes 21 hours and 55 minutes to complete a 3D-printed sundial.

One fascinating presentation regarded a house in Mexico, which was designed so that the Sun shone onto indoor sundials! The presentation, “El Cerrito Pyramid & The Cosmic Room,” was prepared by the home's owner, Mexican Statistics Professor Ruben Hernandez Herrara. Unfortunately, due to visa problems, Professor Herrara was not able to attend the conference; NASS member Bob Kellogg made the presentation.

NASS member Ken Clark demonstrated how to get more public attention to sundials by mounting small sundials on or near local businesses. With both a presentation and an exhibit, he showed how he set-up a small vertical sundial at a Rita's Italian Ice store in Elizabethtown, Pennsylvania.

In addition to discussing Pittsburgh-area sundials, there were sessions on St. Louis-area sundials and “Gnomonic Activities in Italy.” And, NASS member Will Grant showed photographs of his visit to the Millennial Solar Monument near Antofagasta, Chile. This Monument was constructed in the Southern Hemisphere on the Tropic of Capricorn, the southern-most latitude where the Sun can be directly overhead.

Other presentations included, “A Viking Sunstone Sundial,” “Alternative Sunrise / Sunset Markers,” “Alt-Az Plots on Panoramic Photos,” “An Hours to Sunset Solar Decliner Reflection Sundial,” “An Original Bifilar Sundial With Helix Wires,” and “A Sundial With A Helix Polar Gnomon Showing Civil Time.”

The annual Sawyer Dialing Prize was awarded to Italian NASS member Gianpiero Casalegno for creating computer software tools to assist in the development of new sundials. Mr. Casalegno donated the small cash prize to a new sundial being built in Seattle.

At age 25, the North American Sundial Society is one of the oldest sundial science and educational organizations. Only the British Sundial Society is older, at age 29.

Mr. Sawyer emphasizes that researching sundials is multidisciplinary, including several academic areas such as science, mathematics, technology, history, and culture.

From time-to-time, the NASS assists in some public educational programs, including a STEM (Science-Technology-Engineering-Math) festival in Washington DC a few years ago. More recently, NASS participated in a program at the National Archives, again in Washington.

NASS, which publishes a quarterly journal, has also participated in a history book project with the Adler Planetarium in Chicago. And, from time-to-time NASS members contribute to projects to build new sundials, including a sundial mural expected to be completed next month in Bellingham, Washington.

The local host for the 24th annual conference of the NASS was John Sibenac. In addition to his interest in sundials, Mr. Sibenac produces bookmarks from postage stamps, including the wonderful postage stamp issued last year in commemoration of the Great American Solar Eclipse. A first-of-a-kind stamp, the heat from the touch of a finger transforms the eclipsed Moon into the image of the Moon!

Special Thanks: Fred Sawyer and John Sibenac.

                  “Sundial – original”  Taken between 1894 and 1900, this image shows how the Fort Pitt Sundial would have appeared shortly after it was found by the Fort Pitt Society.  The carvings and numerals are clearly visible and in good condition.  The sundial’s surface was heavily damaged during the 20th century from being exposed to pollution and rain.  Credit - Fort Pitt Society.
Photograph of the sundial discovered buried just outside of the Block House of historic Fort Pitt, in Pittsburgh, in 1894. Found without the gnomon, it is believed to date from 1763 following the Battle of Bushy Run during Pontiac's Rebellion, immediately following the French and Indian War. In addition to receiving a site visit by the North American Sundial Society, this sundial was the topic of one of the history presentations at the Pittsburgh conference.
(Image Source: Fort Pitt Society, Daughters of the American Revolution / Fort Pitt Block House)

Internet Links to Additional Information ---

Sundial: Link >>> https://en.wikipedia.org/wiki/Sundial

North American Sundial Society: Link >>> http://sundials.org/

British Sundial Society: Link >>> http://sundialsoc.org.uk/

Historic Fort Pitt Sundial: Link >>> http://www.fortpittblockhouse.com/sundial/

Library Park Sundial, Carnegie PA:
Link >>> http://andrewcarnegie.tripod.com/photofreelibrary.htm#SD

Another interesting sundial - Bracewell Radio Sundial at Very Large Array Radio Telescope Observatory in New Mexico: Link >>> https://apod.nasa.gov/apod/ap180713.html

Related Blog Posts ---

"Science Museums Rebound After Worst of Pandemic." Tue., 2022 Sept. 27.

Association of Science & Technology Centers (ASTC) 2022 Conference in Pittsburgh.

 "Journey to the Sun !" 2018 Aug. 12.

Link >>> https://spacewatchtower.blogspot.com/2018/08/journey-to-sun.html

 

"Special Solar Eclipse Stamp to be Unveiled During Stonehenge-Type Solstice Event in Wyoming." 2017 June 19.

Link >>> http://spacewatchtower.blogspot.com/2017/06/special-solar-eclipse-stamps-to-be.html


Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
              Wednesday, 2018 August 22.

                             Like This Post? - Please Share!

           More Astronomy & Science News - SpaceWatchtower Twitter Feed:
            Link >>> https://twitter.com/spacewatchtower

        Astronomy & Science Links: Link >>> http://buhlplanetarium.tripod.com/#sciencelinks

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gaw

Glenn A. Walsh --- < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail: < gawalsh@planetarium.cc >
Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
SpaceWatchtower Editor / Author: < http://spacewatchtower.blogspot.com/ >
Formerly Astronomical Observatory Coordinator & Planetarium Lecturer, original Buhl Planetarium & Institute of Popular Science (a.k.a. Buhl Science Center), Pittsburgh's science & technology museum from 1939 to 1991.
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >

Sunday, August 12, 2018

Journey to the Sun !

The United Launch Alliance Delta IV Heavy rocket lifts off from Space Launch Complex 37 at Cape Canaveral Air Force Station at 3:31 a.m. EDT, carrying NASA's Parker Solar Probe.
Launch of the Parker Solar Probe on a 3-month journey to the Sun. The on-time launch (although there was a one-day delay) occurred from Space Launch Complex 37 at the Cape Canaveral Air Force Station in Florida early on Sunday Morning, 2018 August 12. (Image Source: NASA)

By Glenn A. Walsh
Reporting for SpaceWatchtower

Early Sun-day morning (ironically, before local Sun-rise on August 12), NASA launched a mission to the nearest star, our Sun. The Parker Solar Probe will enter and study the solar corona, the Sun's atmosphere, when it arrives in November, for the beginning of a 7-year mission, orbiting the Sun 24 times.

It was just on August 21 of last year, during the Great American Solar Eclipse, that millions of Americans saw the solar corona, safely, with their own eyes. The first data about the Sun, from the Parker Solar Probe, should start arriving in December.

After nearly a 24-hour delay from the original launch time, the Parker Solar Probe was launched, on-time, from Space Launch Complex 37 at the Cape Canaveral Air Force Station in Florida. The early Sunday morning (2018 August 12) darkness was disrupted at 3:31:56 a.m. Eastern Daylight Saving Time (EDT) / 7:31:56 Coordinated Universal Time (UTC) when the 1,400-pound / 635.029318 kilogram probe, about the size of a small automobile, lifted-off.

“That’s a relatively light spacecraft,” said Andy Driesman, Project Manager for the mission at the Johns Hopkins University Applied Physics Lab in Laurel, Maryland. “And it needs to be, because it takes an immense amount of energy to get to our final orbit around the Sun.”

Being launched on one of the most powerful rockets in the world, a United Launch Alliance Delta IV Heavy Rocket (with a rocket third-stage), this rocket has 55 times more energy than is required to reach Mars! About two hours after launch, at 5:33 a.m. EDT / 9:33 UTC, the mission operations manager reported that the spacecraft was healthy and operating normally.

It takes a lot of fuel to place even a fairly light-weight object into Outer Space. By about a minute or-so after launch, the entire rocket was half the weight it was at the time of launch! The fuel consumed in the launch constitutes the rocket's lost weight.

The first time NASA has ever named a space mission after a living person, the Parker Solar Probe is named after American astrophysicist Dr. Eugene Parker, the S Chandrasekhar Distinguished Service Professor Emeritus, Department of Astronomy and Astrophysics at the University of Chicago. Now age 91, Dr. Parker viewed the launch at Cape Canaveral this morning.

It was 60 years ago near the beginning of the Space Age, in 1958 at about the same time that NASA was officially established, that Dr. Parker published an academic paper which developed the theory of the solar wind, the stream of charged particles and magnetic fields that flow continuously from the Sun, after observing that as a comet approaches the Sun the comet's tail always points away from the Sun. He also predicted the “Parker Spiral” shape of the solar magnetic field extending into the Outer Solar System.

This project has literally been in the planning for the last 60 years, since the publication of Dr. Parker's academic paper. Only now have we been able to develop the technologies that will allow the Parker Solar Probe to travel close to the Sun, safely.

“NASA was planning to send a mission to the solar corona for decades, however,
we did not have the technology that could protect a spacecraft and its instruments from the heat,” said Adam Szabo, the Mission Scientist for the Parker Solar Probe at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “Recent advances in materials science gave us the material to fashion a heat shield in front of the spacecraft not only to withstand the extreme heat of the Sun, but to remain cool on the backside.”

The most important technology developed was the shadow heat shield, made of a reinforced carbon-carbon composite. This will protect the scientific instruments from the solar corona's intense heat and radiation. While the Sun-facing side simmers at +2,500 degrees Fahrenheit / +1,371.11 degrees Celsius, behind the shield the spacecraft will be a cozy +85 degrees Fahrenheit / +29.44 degrees Celsius.

Energy to power the spacecraft and scientific instruments will come from two solar, photo-voltaic power arrays. The larger, primary array is used until the spacecraft gets close to the Sun; then it is retracted behind the shadow shield. The smaller, secondary array will power the spacecraft at the closest approaches to the Sun. A pumped-fluid cooling system will be used to keep the secondary array from over-heating.

NASA Parker Solar Probe Project Scientist Nicky Fox, with the Johns Hopkins University Applied Physics Lab, describes the probe as "the most autonomous. spacecraft that has ever flown." She goes on to say, “We’ll be going where no spacecraft has dared go before — within the corona of a star...With each orbit, we’ll be seeing new regions of the Sun’s atmosphere and learning things about stellar mechanics that we’ve wanted to explore for decades.”

Greater spacecraft autonomy is necessary because much of the time, particularly when the spacecraft is on the other side of the Sun from Earth, the probe will be out of communication with Earth scientists, due to the great amount of radio noise that comes from the Sun. And, even when the probe is within communication range, it will take eight and one-third minutes to send a command to the spacecraft, as it takes light eight and one-third minutes to travel from the Sun to the Earth.

To reach the Sun, the Parker Solar Probe will use a gravity-assist from the Planet Venus. But, unlike other gravity-assist missions which help the spacecraft to speed-up, in this mission the Parker Solar Probe actually gives-up some energy to Venus to slow-down the spacecraft and ensure a more directed solar orbit for the probe.

In fact, the probe will orbit Venus seven times before it reaches the final, quite eccentric solar orbit. Actually, all of the probe's orbits will be highly elliptical, to reduce the amount of time the probe's scientific instruments and electrical systems have to be exposed to the spacecraft charging effects, highly-charged particles, radiation, and heat from the near-solar environment. And, at closest approach to the Sun at a distance of only 3.83 million statute miles / 6.16378752 million kilometers, this will be the closest any human-made object has gotten to our Sun!

Although the probe will orbit Venus seven times, as it perfects its solar orbit, only one passage of Venus will permit data about Venus to be collected and sent back to scientists on Earth. On the other six passages of Venus, the scientific instruments will be off, to allow the spacecraft's limited power to transmit solar data back to Earth.

On the closest orbit to the Sun, the Parker Solar Probe will be traveling 430,000 miles per hour / 692,017.92 kilometers per hour, becoming the fastest human-made object ever built! At this speed, the probe would take but one second to travel from Philadelphia to Washington, DC !

There are three primary goals of this mission:

  • Determine why the surface (photosphere) of the Sun is only about +10,000 degrees Fahrenheit / +5,500 degrees Celsius, while the atmosphere (corona) is much hotter: ranging from +1.7 million degrees Fahrenheit / +1 million degrees Celsius to more than +17 million degrees Fahrenheit / +10 million degrees Celsius, according to the National Solar Observatory (NSO) Sacramento Peak in Sunspot, New Mexico. Scientists also want to know how this extra heating of the corona accelerates the solar wind.
  • Determine the structure and dynamics of the solar wind's magnetic fields.
  • Determine how energetic particles are transported and accelerated.

In particular, scientists want to learn more about how the Sun affects Space Weather, that is the extreme events in the solar corona which send-out highly-charged particles and radiation that often affects electrical systems on Earth and in Earth orbit. The gases and plasma in the Sun create strong magnetic fields, which often become twisted due to the uneven rotation of the Sun, creating sunspots, solar flares, and coronal mass ejections. The particles and radiation sent-out by these explosive events can effect radio communications, GPS, and satellites, disrupt electrical grids, and endanger astronauts.

“All of our data on the corona so far have been remote,” said Nicholeen Viall, Solar Physicist at NASA's Goddard Space Flight Center. “We have been very creative to get as much as we can out of our data, but there is nothing like actually sticking a probe in the corona to see what’s happening there.” 

Below the probe's high-gain antenna is a plaque which dedicates the mission to Dr. Parker and includes a quote from the scientist: “Let’s see what lies ahead.” The plaque has a memory-card, which includes the names of over 1.1 million people; NASA solicited these names from interested members of the general public. The memory-card also includes photographs of Dr. Parker, along with a copy of his 1958 scientific paper.

Internet Links  to Additional Information ---

Parker Solar Probe -
Link 1 >>> https://www.nasa.gov/content/goddard/parker-solar-probe
Link 2 >>> https://en.wikipedia.org/wiki/Parker_Solar_Probe

More News Regarding Parker Solar Probe Mission -
Link 1 >>> https://blogs.nasa.gov/parkersolarprobe/
Link 2 >>> https://www.nasa.gov/feature/goddard/2018/nasa-s-parker-solar-probe-is-about-to-lift-off

Earth's Sun -
Link 1 >>> https://www.nasa.gov/feature/want-to-learn-more-about-the-sun-here-s-how
Link 2 >>> https://en.wikipedia.org/wiki/Sun

Celestial Star: Link >>> https://en.wikipedia.org/wiki/Star

Solar Eclipse / Eclipse of the Sun: Tips for Safe Viewing:
Link >>> http://buhlplanetarium2.tripod.com/FAQ/soleclipse/solareclipseviewingtips.html

Related Blog Post ---

"Great American Solar Eclipse Early Mega-Movie & Balloon Images." 2017 Aug. 26.

Link >>> https://spacewatchtower.blogspot.com/2017/08/great-american-solar-eclipse-early-mega.html


Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
              Sunday, 2018 August 12.

                             Like This Post? - Please Share!

           More Astronomy & Science News - SpaceWatchtower Twitter Feed:
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gaw

Glenn A. Walsh --- < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail: < gawalsh@planetarium.cc >
Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
SpaceWatchtower Editor / Author: < http://spacewatchtower.blogspot.com/ >
Formerly Astronomical Observatory Coordinator & Planetarium Lecturer, original Buhl Planetarium & Institute of Popular Science, Pittsburgh's science & technology museum from 1939 to 1991.
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >

Wednesday, August 1, 2018

Astronomical Calendar: 2018 August


Image of a 2007 Perseid Meteor, just to the right from the Milky Way. The Perseid Meteor Shower, one of the best meteor showers of the year, will be even better this year as the Moon will be in New Moon phase (Lunation # 1183) on August 11 at 5:58 a.m. EDT / 9:58 UTC, and moonlight will not interfere with meteor viewing during this meteor shower's peak (Perseid Meteor Shower runs from July 14 to August 24, with the peak occurring Sat., Aug. 12, 9:00 p.m. EDT / Aug. 13, 1:00 UTC - Best viewing: Aug. 11, 12, & 13, Midnight to Dawn). And, Mars will continue to be a bright beacon in the night sky for another month or so. More info on viewing Mars this Summer:
Link >>> http://spacewatchtower.blogspot.com/2018/07/mars-bright-beacon-in-sky-in-july-august.html
(Image Sources: Wikipedia.org, By Brocken Inaglory - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=2632873)

Astronomical Calendar for 2018 August ---
Link >>> http://buhlplanetarium4.tripod.com/astrocalendar/2018.html#aug


 Related Blog Posts ---

"Science Experiments Children & Teens Can Do At Home !" 2018 June 5.

Link >>> https://spacewatchtower.blogspot.com/2018/06/science-experiments-children-teens-can.html

 

"Astronomical Calendar: 2018 July." 2018 July 1.

Link >>> http://spacewatchtower.blogspot.com/2018/07/astronomical-calendar-2018-july.html


Source: Friends of the Zeiss.
              Wednesday, 2018 August 1.

                             Like This Post? - Please Share!

            More Astronomy & Science News - SpaceWatchtower Twitter Feed:
            Link >>> https://twitter.com/spacewatchtower

        Astronomy & Science Links: Link >>> http://buhlplanetarium.tripod.com/#sciencelinks

                Want to receive SpaceWatchtower blog posts in your in-box ?
                Send request to < spacewatchtower@planetarium.cc >.

gaw

Glenn A. Walsh --- < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail: < gawalsh@planetarium.cc >
Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
SpaceWatchtower Editor / Author: < http://spacewatchtower.blogspot.com/ >
Formerly Astronomical Observatory Coordinator & Planetarium Lecturer, original Buhl Planetarium & Institute of Popular Science (a.k.a. Buhl Science Center), Pittsburgh's science & technology museum from 1939 to 1991.
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >