Wednesday, July 3, 2024

Dog Days of Summer Begin, As Earth Farthest from Sun!

  


While the Orion constellation can be seen to the right, the bright star Sirius, the "Dog Star", can be seen at the bottom of this image. (Image Sources: European Space Agency, NASA, Wikipedia.org, By Hubble European Space AgencyCredit: Akira Fujii - http://www.spacetelescope.org/images/heic0206j/ (watermark was cropped), Public Domain, https://commons.wikimedia.org/w/index.php?curid=5246351)

By Glenn A. Walsh

Reporting for SpaceWatchtower

We are now entering the “Dog Days of Summer” in Earth's Northern Hemisphere. However, this is also the time of year, shortly after the Northern Hemisphere's Summer Solstice, when the Earth is actually farthest from the Sun (known as Earth Aphelion) !

Today, the Dog Days of Summer are considered the days between July 3 and August 11 each year. These Dog Days begin just a little less than two weeks after the Summer Solstice, the official beginning of Summer in the Northern Hemisphere.

For A.D. 2024, the season of Summer began at Earth's Northern Hemisphere's Summer Solstice (and the season of Winter begins at the Southern Hemisphere's Winter Solstice) at the moment of the June Solstice: Thursday Afternoon, 2024 June 20 at 4:51 p.m. Eastern Daylight Saving Time (EDT) / 20:51 Coordinated Universal Time [UTC – International time used by scientists; previously referred to as Greenwich Mean Time (GMT) or Greenwich Civil Time (GCT)]. Summer will continue in the Northern Hemisphere (and Winter will continue in the Southern Hemisphere) until the Autumnal Equinox when the season of Autumn / Fall commences in the Northern Hemisphere (and Spring begins in the Southern Hemisphere): Sunday Morning, 2024 September 22 at 8:44 a.m. EDT / 12:44 UTC.

In Meteorology (Weather Science), the convention is to start a season on the first day of a calendar month. So, Meteorological Summer runs from June 1 to August 31.

Also within the Dog Days of Summer come the traditional Cross-Quarter (XQ) Day known as Lammas (Anglo-Saxon) or Lughnasadh (Irish / Scottish) on August 1. Located approximately half-way between the Summer Solstice and the Autumnal Equinox, this day has long been considered the beginning of harvesting crops.

Lammas / Lughnasadh Day, in ancient times,was a festival day which marked the start of the harvest season, particularly the wheat harvest. On Lammas Day, it was customary to bring a loaf of bread, from the new crop, to church to be blessed.

August 1 also marks the anniversary of the birth of America's first professional, female astronomer. Maria Mitchell, Professor of Astronomy at Vassar College and discoverer of Miss Mitchell's Comet in 1847, was born on 1818 August 1 in Nantucket, Massachusetts.

While August 1 is the traditional Cross-Quarter Day, due to calendar changes over the years, in modern times the actual Cross-Quarter Day differs by as much as a week. For 2024, Lammas / Lughnasadh Day actually occurs on Tuesday, 2024 August 6 at 8:10 p.m. EDT / August 7 at 0:10 UTC.

Dog Days of Summer

So, how did these days become known as the Dog Days of Summer?

First, we need to look at the pictures in the sky that ancient peoples saw in the stars, now known as constellations. One of the most recognized constellations is that of Orion the Hunter (Ori).

And, many hunters have one or more hunting dogs to assist them. This was also true in Greek mythology for Orion. Orion's two dogs, Canis Majoris or Canis Major (CMa: Greater Dog) and Canis Minoris Canis Minor (CMi: Lesser Dog), were each given their own constellation.

The brightest star in Canis Major also happens to be the brightest star in Earth's night sky, the star Sirius (Alpha CMa or a CMa). And, being the brightest star in Canis Major, Sirius is known as the “Dog Star”. Sirius is located 8.611 light-years from the Earth and has an astronomical, Apparent Visual Magnitude of brightness of -1.45.

Being the brightest star in the night sky, ancient Romans assumed that Sirius provided heat to the Earth, as did our Solar System's Sun. During the Summer months, Sirius rises and sets at generally the same time as our Sun. Even in ancient times, astronomers were able to use mathematics to determine the rising and setting times of a star in the daytime sky.

The Romans believed that heat from Sirius, added to the heat from the Sun, caused the Summer months to be so much hotter than the rest of the year. Hence, the middle of the Summer season in Earth's Northern Hemisphere, now during July 3 to August 11 (the actual dates varied, somewhat, in ancient times), has become known as the Dog Days of Summer.

Today, we realize that a star 8.611 light-years away, no matter how bright, can never provide enough heat to affect life on Earth. Further, even the annual, variable distance between Earth and our own Sun is not the reason for the additional heat in the Northern Hemisphere during the Summer months.

Earth Aphelion

Although the Summer months in the Northern Hemisphere are known for the year's warmest weather, the Earth is actually at the point in its orbit farthest from the Sun (astronomically known as the point of Aphelion) around July 5. This Friday morning, just one day after the day we celebrate the 248th year of American Independence on July 4 and a couple weeks after the Summer Solstice on June 20, will mark Aphelion for 2024, the location in Earth's annual orbit around the Sun where our planet is farthest from the Sun for the entire year!

This year, Earth Aphelion will occur early on Friday Morning, 2024 July 5 at 1:06 a.m. Eastern Daylight Saving Time (EDT) / 5:06 Coordinated Universal Time [UTC – International time used by scientists; previously referred to as Greenwich Mean Time (GMT) or Greenwich Civil Time (GCT)]. At that moment, Earth will be the farthest from the Sun for the whole year: 94,510,539 statute miles / 152,099,968 kilometers.

Earth's closest approach to the Sun this year (known astronomically as Perihelion) occurred on 2024 January 2 at 7:38 p.m. Eastern Standard Time (EST) / January 3 at 0:38 UTC, at a distance of 91,404,095 statute miles / 147100631.86 kilometers. Next year, Perihelion occurs on 2025 January 4 at 8:28 a.m. EST / 13:28 UTC, at a distance of 91,405,993 statute miles / 147103686.4 kilometers.

In general, the distance from the Earth to the Sun is not the major factor determining the heat of Summer or the cold of Winter. This is true, despite the fact that Earth receives about 7 per-cent more solar radiation from the Sun during the time of Earth Perihelion in January, than at the time of Earth Aphelion in July.

Solar radiation, and hence the heat from the Sun, depends on the length of daylight and the angle of the Sun above the horizon. The tilt of the planet's axis, about 23.44 degrees toward the Sun, determines the additional and more direct solar radiation received by a planet's Northern or Southern Hemisphere, and hence, the warmer season of the respective hemisphere.

While the Sun does have motions (the Sun rotates on its own axis about once every 27 Earth days; our Solar System revolves around the center of the Milky Way Galaxy once every 225 million-to-250 million Earth years), it is actually the motion of the Earth tilted on its axis, away from the plane of the ecliptic (Earth's orbital plane around the Sun), while revolving around the Sun, that causes the Earth's seasons.

The Earth's Perihelion in January, and Aphelion in July, are due to the elliptical nature of the Earth's orbit around the Sun. Perihelion and Aphelion would not occur if the Earth's orbit was a true circle.

The dates of Earth Perihelion and Earth Aphelion are not fixed. Due to the Earth's Precession of the Equinoxes, these days shift forward approximately one day every 58 years. About 800 years ago, the Earth Perihelion was on the date of the Winter Solstice, around December 21; Earth Perihelion will be on the Vernal Equinox, the beginning of Spring around March 20, about 4,300 years from now. Earth's Axial Precession (often described as a "wobble" in the Earth's orientation, like a spinning top or a gyroscope) gradually changes the orientation of the Earth's Rotational Axis, which completes one rotational cycle once every 25,772 years.

However, because Earth is farther from the Sun during our Spring and Summer seasons, people in Earth's Northern Hemisphere actually benefit from a few extra days of warmth (on average), than the number of days in the Autumn and Winter seasons of the year. When Earth is closer to the Sun, the Earth travels faster in its elliptical orbit around the Sun (during the Autumn and Winter months); and, when Earth is farther than average from the Sun (during the Spring and Summer seasons) the Earth travels a little more slowly (Kepler's Second Law of Planetary Motion) --- again, this refers to the Northern Hemisphere. Hence, the Spring and Summer seasons, in the Northern Hemisphere, have a few more days than the Autumn and Winter seasons.

In fact, the late Jay Pasachoff, who was Field Memorial Professor of Astronomy at Williams College in Williamstown, Massachusetts and author of widely-used, college astronomy text-books, precisely calculated the duration of each season in the Northern Hemisphere:

* Summer: 93 days, 15 hours

* Spring: 92 days, 19 hours

* Autumn / Fall: 89 days, 20 hours

* Winter: 89 days, 0 hours

Internet Links to Additional Information ---

Dog Days of Summer -

Link 1 >>> https://wilstar.com/dogdays/

Link 2 >>> https://en.wikipedia.org/wiki/Dog_days

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

Constellation Canis Major: Link >>> https://en.wikipedia.org/wiki/Canis_Major

Science Experiments Children & Teens Can Do At Home During Summer Break !


Related Blog-Posts ---

"Summer Begins Thursday Afternoon at Solstice." Mon., 2024 June 17.


"Earth Farthest from Sun for Year: Thursday." Mon., 2023 July 3.


1st U.S. Female Professional Astronomer: Leading Women's Suffragist." Wed., 2020 Aug. 26.


"Astronomical Mid-Point of Summer." Tue., 2013 July 30.

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

               "Dog Days of Summer Begin, As Earth Farthest from Sun!"

                  Wednesday, 2024 July 3.

            Artificial Intelligence not used in the writing or production of this article.

            © Copyright 2024 Glenn A. Walsh, All Rights Reserved

                             Like This Post? Please Share!

More Astronomy & Science News - SpaceWatchtower 'X' / 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, Informal Science Educator & Communicator                                                             (For more than 50 years! - Since Monday Morning, 1972 June 12):
Link >>> http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/
Electronic Mail: < gawalsh@planetarium.cc >
Project Director, Friends of the Zeiss: Link >>> http://buhlplanetarium.tripod.com/fotz/
SpaceWatchtower Editor / Author: Link >>> http://spacewatchtower.blogspot.com/
Formerly Astronomical Observatory Coordinator & Planetarium Lecturer, original Buhl Planetarium & Institute of Popular Science (a.k.a. Buhl Science Center), America's fifth major planetarium and Pittsburgh's science & technology museum from 1939 to 1991.
Formerly Trustee, Andrew Carnegie Free Library and Music Hall, Pittsburgh suburb of Carnegie, Pennsylvania, the fourth of only five libraries where both construction and endowment funded by famous industrialist & philanthropist Andrew Carnegie.
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh: Link >>> http://www.planetarium.cc Buhl Observatory: Link >>> http://spacewatchtower.blogspot.com/2016/11/75th-anniversary-americas-5th-public.html
* Adler Planetarium, Chicago: Link >>> http://adlerplanetarium.tripod.com
* Astronomer, Educator, Optician John A. Brashear: Link >>> http://johnbrashear.tripod.com
* Andrew Carnegie & Carnegie Libraries: Link >>> http://www.andrewcarnegie.cc

 * Other Walsh-Authored Blog & Web-Sites: Link >>> https://buhlplanetarium.tripod.com/gawweb.html

Monday, June 17, 2024

Summer Begins Thursday Afternoon at Solstice

            

By Glenn A. Walsh

Reporting for SpaceWatchtower

Late Thursday afternoon, Summer begins in the Northern Hemisphere of Earth, while at the same time, Winter begins in the Southern Hemisphere.

For A.D. 2024, the season of Summer begins at Earth's Northern Hemisphere's Summer Solstice (and the season of Winter begins at the Southern Hemisphere's Winter Solstice) at the moment of the June Solstice: Thursday Afternoon, 2024 June 20 at 4:51 p.m. Eastern Daylight Saving Time (EDT) / 20:51 Coordinated Universal Time [UTC – International time used by scientists; previously referred to as Greenwich Mean Time (GMT) or Greenwich Civil Time (GCT)]. Summer will continue in the Northern Hemisphere (and Winter will continue in the Southern Hemisphere) until the Autumnal Equinox when the season of Autumn / Fall commences in the Northern Hemisphere (and Spring begins in the Southern Hemisphere): Sunday Morning, 2024 September 22 at 8:44 a.m. EDT / 12:44 UTC.

In Meteorology (Weather Science), the convention is to start a season on the first day of a calendar month. So, Meteorological Summer runs from June 1 to August 31.

In Etymology, the word Solstice comes from the Latin terms Sol (Sun) and Sistere (to stand still). In ancient times, Astronomers / Astrologers / Priests recognized that on one day of the year (in the Northern Hemisphere, on or near the day we now call June 21), the Sun would appear to stand-still (regarding the Sun's apparent move higher or lower in the sky, from day-to-day) as Sol reaches its highest point in the sky for the entire year. The motion of the Sun's apparent path in the sky (daily motion higher or lower in the sky, what is known astronomically, today, as the Sun's Declination) would cease on this day, before appearing to reverse direction.

Although the Summer months in the Northern Hemisphere are known for the year's warmest weather, the Earth is actually at the point in its orbit farthest from the Sun (astronomically known as the point of Aphelion) around July 5. The Earth's closest approach to the Sun (Perihelion) each year is around January 2. Hence, in general, the distance from the Earth to the Sun is not the major factor determining the heat of Summer or the cold of Winter.

This year, Earth Aphelion will occur early on Friday Morning, 2024 July 5 at 1:00 a.m. EDT / 5:00 UTC. At that moment, Earth will be the farthest from the Sun for the whole year: 94,510,538.455 statute miles / 152,099,968 kilometers.

However, because Earth is farther from the Sun during our Spring and Summer seasons, people in Earth's Northern Hemisphere actually benefit from a few extra days of warmth (on average), than the number of days in the Autumn and Winter seasons of the year. When Earth is closer to the Sun, the Earth travels faster in its elliptical orbit around the Sun (during the Autumn and Winter months); and, when Earth is farther than average from the Sun (during the Spring and Summer seasons) the Earth travels a little more slowly (Kepler's Second Law of Planetary Motion) --- again, this refers to the Northern Hemisphere. Hence, the Spring and Summer seasons, in the Northern Hemisphere, have a few more days than the Autumn and Winter seasons.

In fact, the late Jay Pasachoff, who was Field Memorial Professor of Astronomy at Williams College in Williamstown, Massachusetts and author of widely-used, college astronomy text-books, precisely calculated the duration of each season in the Northern Hemisphere:

* Summer: 93 days, 15 hours

* Spring: 92 days, 19 hours

* Autumn / Fall: 89 days, 20 hours

* Winter: 89 days, 0 hours 

Solar radiation, and hence the heat from the Sun, depends on the length of daylight and the angle of the Sun above the horizon. The tilt of the planet's axis toward the Sun determines the additional and more direct solar radiation received by a planet's Northern or Southern Hemisphere, and hence, the warmer season of the respective hemisphere.

While the Sun does have motions [the Sun rotates on its own axis, but as a sphere of hot plasma the rotation rate varies by Latitude (at the Solar Equator - Sidereal Rotation Period: 24.47 Earth days, Synodic Rotation Rate: 26.24 Earth days; our Solar System revolves around the center of the Milky Way Galaxy once every 225 million-to-250 million Earth years], it is actually the motion of the Earth tilted on its axis, away from the plane of the ecliptic (Earth's orbital plane around the Sun), while revolving around the Sun, that causes the Earth's seasons.

As of Noon (Prevailing Time) on 2024 June 17, Earth's Axial Tilt or Mean Obliquity: 23.43610° or 23°26'09.9" (Source: TimeandDate.com).

Hence, as the Earth arrives at the point in its orbit around the Sun, when the north polar axis is most directly inclined toward the Sun, this marks the Summer Solstice in the Northern Hemisphere and the Winter Solstice in the Southern Hemisphere.

Alternately, the Winter Solstice in the Northern Hemisphere (the Winter Solstice is always on or near, what we now refer to as, December 21) occurs when the Earth reaches the point in its orbit when the North Pole is most directly inclined away from the Sun (and, the South Pole is most directly inclined toward the Sun). And, conversely, at this time Summer begins in the planet's Southern Hemisphere.

For Earth observers at the North Latitude which matches the Earth's Axial Tilt or Obliquity, at the moment of the June Solstice, the Sun will appear to shine directly overhead. The line around the Earth at the North Latitude which matches the Earth's Axial Tilt or Obliquity is known as the Tropic of Cancer (a.k.a. Northern Tropic). Likewise, the South Latitude which matches the Earth's Axial Tilt or Obliquity is located at the Tropic of Capricorn (a.k.a. Southern Tropic), where the Sun appears directly overhead at the moment of the December Solstice.

However, as the tilt of the Earth is dynamic, and changes minutely over the years, the location of the Tropic lines also change. Currently, these Tropic lines are moving north at the rate of 0.47 arc-seconds / 49.21 feet / 15 meters per year.

The names Tropic of Cancer and Tropic of Capricorn were coined in the last centuries B.C., when the Sun would appear in the Constellation Cancer the Crab on the June Solstice and in the Constellation Capricornus the Horned Goat on the December Solstice. However today, hours after the June Solstice, the Sun enters the Constellation Gemini the Twins, 30 degrees from Cancer. And at the December Solstice, the Sun is now in the Constellation Sagittarius the Archer.

This is due to “Precession of the Equinoxes” of Earth, which is analogous to the wobbling of a spinning top. In the case of the Earth, this 25,772-year wobble causes observers to view the Sun in different parts of the sky over the centuries, at the same time of year while remaining in the same geographical location. As the Earth wobbles over the centuries, the North Pole Star also changes. Currently, Polaris is our North Pole Star; around A.D. 13,700, Vega will be our North Pole Star, due to the Precession of the Equinoxes.

No matter which hemisphere, the day of the Summer Solstice always has the most hours and minutes of daylight (the length of time between Sunrise and Sunset) for the year, while the Winter Solstice always has the least number of hours and minutes of daylight for the year. The exact number of hours and minutes of daylight, for a particular location, depends on the locale's geographic Latitude on the Earth. Astronomers, amateur ("ham") radio operators, and long-distance radio enthusiasts (“radio DXers”), all of whom mostly depend on non-daylight hours to ply their craft, often prefer the days closer to the Winter Solstice.

The Vernal Equinox, when the season of Spring begins in the Northern Hemisphere (and the season of Autumn begins in the Southern Hemisphere), occurs between the Winter and Summer Solstices when the Earth reaches the point in its orbit around the Sun when the Earth's axis is inclined neither toward nor away from the Sun. Likewise, when the Earth reaches the point in its orbit around the Sun, between the Summer and Winter Solstices, when the Earth's axis is inclined neither toward nor away from the Sun, this is known as the Autumnal Equinox (beginning of Fall or Autumn) in the Northern Hemisphere; at this time Spring begins in the Southern Hemisphere. And, half-way between the beginning points of each season are Cross-Quarter Days, each related to traditional holidays: Groundhog Day (February 2), May Day (May 1), Lammas Day (traditionally, the first harvest festival of the year on August 1), and Halloween (October 31).

In ancient times, the Summer Solstice was known as Mid-Summer Day, in early calendars observed around June 24. At that time, May 1 to August 1 (i.e. the two Cross-Quarter Days) was considered the season of Summer. Such early European celebrations were pre-Christian in origin. Many will associate this ancient holiday with the famous William Shakespeare play, “A Midsummer Night's Dream.” Some speculate that the play was written for the Queen of England, to celebrate the Feast Day of Saint John.

As with the Roman Catholic Church's decision to Christianize the pagan Winter Solstice festivals with the introduction of Christmas Day on December 25 (by an early calendar, December 25 was reckoned as the Winter Solstice), the Church began to associate the Mid-Summer festivals with the Nativity of Saint John the Baptist on June 24. In the Christian Bible, the Gospel of Saint Luke implies that Saint John was born six months before the birth of Jesus, although no specific birth dates are given.

The most famous celebration of the Summer Solstice occurs each year at the Stonehenge pre-historic monument in England. Constructed between 3,000 B.C. and 1,600 B.C. in three phases, the actual purpose of the landmark is still unclear. However, it seems to have been associated with burials, originally. It was also used as a type of astronomical observatory, particularly for observing the Sun, which was important to help early cultures make annual decisions regarding agriculture.

Stonehenge is known as a way for pre-historic peoples to mark both the Summer and Winter Solstices. From inside the monument, a viewer facing northeast can watch the Sun rise (weather-permitting) above a stone outside the main circle of rocks, known as the Heel Stone, on the day of the Summer Solstice in the Northern Hemisphere. Although today, due to serious erosion of the stones, visitors on the Summer Solstice can only walk around the landmark from a short distance away during this annual event.

Although not as prominent as Stonehenge, a calendar ring using smaller rocks was also constructed at Nabta Playa in southern Egypt, perhaps as early as 7,000 years ago! As with Stonehenge, some stones aligned with Sunrise on the day of the Summer Solstice.

Today, a Stonehenge-like event occurs each year at the University of Wyoming (UW) Art Museum in Laramie, Wyoming, free-of-charge to the general public. At 12:00 Noon Mountain Daylight Saving Time (MDT) / 2:00 p.m. EDT / 18:00 UTC on the day of the Summer Solstice, visitors can see a single beam of sunlight shine through a solar tube in the ceiling of the UW Art Museum's Rotunda Gallery; the beam of sunlight then shines onto a 1923 Peace Silver Dollar embedded in the floor of the Museum's Rotunda Gallery. Visitors are encouraged to arrive at the museum by 11:30 a.m. MDT / 1:30 p.m. EDT / 17:30 UTC, to view this rather unique architectural feature.

The bright Star Spica (Alpha Virginis), the brightest star in the Constellation Virgo the Virgin and the 16th brightest star in Earth's night sky (Apparent Visual Magnitude: + 0.97), may have helped develop another one of civilization's early calendars. A calendar of ancient Armenia used the year's first sighting of Spica in the dawn sky, a few days before the Summer Solstice, to mark the beginning of the New Year for this particular calendar. The development of this calendar somewhat coincided with the beginning of agriculture in Armenia.

Like clock-work, a well-known asterism (pattern of stars in the sky, not officially recognized as a constellation) of three stars shaped as a triangle is visible nearly overhead around local midnight during the Summer months (weather-permitting). And logically, as Star Trek's Mr. Spock might say, this asterism is known as the Summer Triangle!

Three of the brightest stars in the Summer sky constitute the Summer Triangle ---

  1. Vega (Alpha Lyrae - brightest star in the Constellation Lyra the Harp); brightest of the three stars and closest to the zenith (highest point in the sky);

  2. Altair (Alpha Aquilae - denotes the eagle eye and brightest star in the Constellation Aquila the Eagle); second brightest star of the trio;

  3. Deneb (Alpha Cygni - denotes the tail star, is the brightest star in the Constellation Cygnus the Swan, and is the “head” star of the asterism known as the Northern Cross).

The term Summer Triangle was popularized in the 1950s by American author H.A. Rey and British astronomer Patrick Moore, although constellation guidebooks mention this triangle of stars as far back as 1913. And, during World War II, military navigators referred to this asterism as the “Navigator's Triangle.”

Regardless of city light pollution, the three bright stars of the Summer Triangle should be visible to nearly everyone in Earth's Northern Hemisphere (weather-permitting). So, just look overhead late-evening or early-morning throughout the Summer for these annual visitors to our Summer sky!

Internet Links to Additional Information ---

Axial Tilt / Obliquity:

Link 1 >>> https://www.timeanddate.com/astronomy/axial-tilt-obliquity.html

Link 2 >>> https://en.wikipedia.org/wiki/Axial_tilt

Summer Solstice: 
Link 1 >>> http://scienceworld.wolfram.com/astronomy/SummerSolstice.html 
Link 2 >>> http://en.wikipedia.org/wiki/Summer_solstice  

Season of Summer: Link >>> http://en.wikipedia.org/wiki/Summer  

History of Mid-Summer: Link >>> http://en.wikipedia.org/wiki/Midsummer
 
Summer "Solstice Day" Annual Free-of-Charge Day (With Snowballs !), 1985 to 1991, at the original Buhl Planetarium and Institute of Popular Science (a.k.a. Buhl Science Center), America's 5th Major Planetarium and Pittsburgh's science and technology museum from 1939 to 1991:  
Link >>> http://spacewatchtower.blogspot.com/2015/06/snowballs-on-first-day-of-summer.html

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

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

Precession of the Equinoxes: Link >>> https://en.wikipedia.org/wiki/Axial_precession 

Tropic of Cancer: Link >>> https://en.wikipedia.org/wiki/Tropic_of_Cancer 

Tropic of Capricorn: Link >>> https://en.wikipedia.org/wiki/Tropic_of_Capricorn 

Summer Triangle: Link >>> https://en.wikipedia.org/wiki/Summer_Triangle

Science Experiments Children & Teens Can Do At Home During Summer Break !

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

               "Summer Begins Thursday Afternoon at Solstice"

                  Monday, 2024 June 17.

            Artificial Intelligence not used in the writing or production of this article.

            © Copyright 2024 Glenn A. Walsh, All Rights Reserved

                             Like This Post? Please Share!

More Astronomy & Science News - SpaceWatchtower 'X' / 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, Informal Science Educator & Communicator                                                             (For more than 50 years! - Since Monday Morning, 1972 June 12):
Link >>> http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/
Electronic Mail: < gawalsh@planetarium.cc >
Project Director, Friends of the Zeiss: Link >>> http://buhlplanetarium.tripod.com/fotz/
SpaceWatchtower Editor / Author: Link >>> http://spacewatchtower.blogspot.com/
Formerly Astronomical Observatory Coordinator & Planetarium Lecturer, original Buhl Planetarium & Institute of Popular Science (a.k.a. Buhl Science Center), America's fifth major planetarium and Pittsburgh's science & technology museum from 1939 to 1991.
Formerly Trustee, Andrew Carnegie Free Library and Music Hall, Pittsburgh suburb of Carnegie, Pennsylvania, the fourth of only five libraries where both construction and endowment funded by famous industrialist & philanthropist Andrew Carnegie.
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh: Link >>> http://www.planetarium.cc Buhl Observatory: Link >>> http://spacewatchtower.blogspot.com/2016/11/75th-anniversary-americas-5th-public.html
* Adler Planetarium, Chicago: Link >>> http://adlerplanetarium.tripod.com
* Astronomer, Educator, Optician John A. Brashear: Link >>> http://johnbrashear.tripod.com
* Andrew Carnegie & Carnegie Libraries: Link >>> http://www.andrewcarnegie.cc

 * Other Walsh-Authored Blog & Web-Sites: Link >>> https://buhlplanetarium.tripod.com/gawweb.html

Saturday, June 8, 2024

Photos: Total Solar Eclipse Viewed in Cleveland

                

Totality Phase of the Total Solar Eclipse / Total Eclipse of the Sun, as seen at the Total Eclipse Fest 2024 at the Great Lakes Science Center / NASA Glenn Research Center Visitors' Center, along the Lake Erie Waterfront in Downtown Cleveland. This photograph was taken on Monday Afternoon, 2024 April 8 at 3:15 p.m. EDT / 19:15 UTC. Camera used: Apple I-Phone 12-Mini, using application: "Solar Snap".

(Image Source: Friends of the Zeiss, Photographer: Jim McKee)

Photographs of all stages of this Total Solar Eclipse / Total Eclipse of the Sun can be found at the following Internet link:

Link >>> https://buhlplanetarium4.tripod.com/eclipse/solar/total/cleveland/NASA2024.html#eclipsepix

By Glenn A. Walsh

Reporting for SpaceWatchtower

Two months ago, on Monday, 2024 April 8, one of the greatest coincidences in nature occurred: a Total Solar Eclipse / Total Eclipse of the Sun, when the Moon completely blocks the view of the entire surface of the Sun, the only time which allows a safe view of the Sun's upper atmosphere known as the Corona. The Cleveland Metropolitan Area was one of a select group of urban centers that was within the Path of Totality of this Total Solar Eclipse. And, it just so happens that Cleveland is also home to a major NASA research center, the NASA John H. Glenn Research Center at Lewis Field, which hosted a large public Eclipse watch at Cleveland's Great Lakes Science Center.

During a Total Solar Eclipse / Total Eclipse of the Sun, the Moon completely obscures the surface of the Sun; it is only during the short time when the surface of the Sun is completely blocked from view (for the April 8 Eclipse: a maximum of approximately 4 minutes and 28 seconds - for some areas it was less time: 3 minutes and 49 seconds in Cleveland) that the Eclipse can be viewed without safety equipment. And during this time, often the Solar Corona (outermost layer of the Sun's atmosphere, which is safe to look at so long as the rest of the Sun's surface is blocked from view) can be seen around the shadow outline of the Moon, and planets and stars can also sometimes be seen at this time. Birds and wildlife often begin nighttime behaviors and the air, no longer heated by the Sun, feels cooler.

The coincidence in nature of a Total Solar Eclipse / Total Eclipse of the Sun is due to the fact that the Sun is approximately 400 times larger than the Moon, but the Sun is also about 400 times further from the Moon. Hence, during a Total Solar Eclipse / Total Eclipse of the Sun, the Moon and Sun appear roughly the same size as we view the two objects in the sky, even though the Sun is much, much larger than the Moon.

A select number of metropolitan areas were included in the Path of Totality for the April 8 Eclipse. These included the metropolitan areas of Little Rock, Indianapolis, Buffalo, Rochester, Syracuse, Akron, Cleveland, Dayton, Toledo, Erie, Austin, Dallas / Fort Worth, Burlington, and Montreal. However, Cleveland is the only city on this list that includes a NASA Research Center, one of 10 major NASA research centers across the United States.

The NASA Visitors' Center for the Glenn Research Center is now sited within the Great Lakes Science Center. The Great Lakes Science Center is located on Downtown Cleveland's Lake Erie waterfront (known as the North Coast Harbor), between the Rock-and-Roll Hall of Fame and the Cleveland Browns National Football League Stadium.

For the Total Solar Eclipse on April 8, NASA organized a huge viewing event on the south side of the Great Lakes Science Center, which was free-of-charge to the general public. Titled “Total Eclipse Fest 2024” and described by NASA as a “free, outdoor, family-friendly science and arts festival”, the event featured free concerts, performances, speakers, and hands-on science activities for children. Some of the exhibit stations / tents included virtual and augmented simulations including flying in a supersonic airplane, walking on Mars, and visiting the International Space Station.

Total Eclipse Fest 2024 was actually a three-day weekend event (2024 April 6 to 8), which included a free-of-charge concert by The Cleveland Orchestra as well as free-of-charge admission to the Great Lakes Science Center, both on Sunday, April 7. This festival was also host to NASA Television's live coverage of the Total Solar Eclipse, on April 8 from 1:00 to 4:00 p.m. Eastern Daylight Saving Time (EDT) / 17:00 to 20:00 Coordinated Universal Time (UTC), from a stage near the exhibit tents.

                    

Photograph of a Moon Rock collected by Apollo astronauts (1969 to 1972).
This Moon Rock is displayed in the NASA Glenn Research Center's educational
exhibit trailer, "Journey to Tomorrow", which was part of the NASA Village during the Total Eclipse Fest 2024 on Monday, 2024 April 8.
(Image Source: Friends of the Zeiss, Photographer:
Pittsburgh-area Free-Lance Photographer Lynne S. Walsh)
Other NASA Moon Rock Exhibits: Link >>> https://buhlplanetarium2.tripod.com/Buhlexhibits.htm#moonrock
Images of other NASA exhibits at the Total Eclipse Fest 2024: Link >>> https://buhlplanetarium4.tripod.com/eclipse/solar/total/cleveland/NASA2024.html#nasaexhibits

The heart of the event was NASA Village, which consisted of 11 educational exhibit stations / outdoor tents plus a large educational trailer (“Journey to Tomorrow”), which highlighted much of the research occurring at the NASA Glenn Research Center:

  1. NASA Village Welcome Center – Where NASA bags and backpacks were handed-out, free-of-charge.

  2. Exploring the Moon – This showed NASA work to 3-D map the Moon and provide power to future Moon exploration.

  3. Rovers and Wheels – Which showed a full-scale replica of an Apollo-era Lunar Rover wheel (in 1971, Apollo 15 was the first mission to use a Lunar Rover on the Moon, with astronauts Dave Scott and Pittsburgh native James Irwin), as well as a full-scale model of the NASA VIPER Rover (which will be launched on the Griffin Lander produced by Pittsburgh's Astrobotic Technology, Inc.) which will soon be sent to the Moon to search for ice and other resources near the lunar South Pole.

  4. Artemis: To the Moon and Beyond – Includes information on how the NASA Glenn Research Center is providing expertise in power and propulsion systems for the Artemis and Orion spacecraft designed to take humans (including the first woman and first person of color) back to the Moon, and the Lunar Gateway Space Station being designed for lunar orbit.

  5. Living and Working in Space – Visitors learned about how astronauts live, work, and conduct experiments in Outer Space, including on the International Space Station.

  6. Meet and Greet – NASA Astronauts Stephen Bowen and Jessica Watkins were available for greeting visitors and for selfie photographs. Also for children, Snoopy, the beagle from the famous Peanuts comic strip and animated television specials, made an appearance in a NASA Artemis flight suit, decked-out in Solar Eclipse Glasses!

  7. Eclipse Glasses – NASA Solar Eclipse Glasses were handed-out, free-of-charge.,

  8. Cleaner Aviation – Showed how NASA uses wind tunnels to simulate flight conditions while testing aircraft and spacecraft models. This area also showed one of the engines, the High-Efficiency Megawatt Motor (HEMM), the NASA Glenn Research Center has designed and is testing to meet the needs of electrified aircraft propulsion.

  9. Air Taxis and Drones – This tent included an Air Taxi virtual reality demonstrator. A hands-on activity also showed how vertical take-off and landing works.

  10. Quesst: Quiet Supersonic Flight – This area showed a model of the NASA X-59 experimental aircraft, which demonstrated supersonic flight without loud sonic booms.

  11. Eclipses and Solar Science – This area talked about why NASA studies the Sun and its influences on the Earth.

  12. NASA Glenn Research Center's 53-foot Educational Traveling Exhibit Trailer: "Journey to Tomorrow" – Includes 8 interactive kiosks (in both English and Spanish languages) with NASA educational exhibits, including a Moon rock collected by Apollo astronauts. As described on the NASA web-site, this traveling exhibit includes: ~Improving Today’s Flight, NASA Home and City which highlights spinoff products created from NASA’s research programs, Sci-Fi vs. Science Fact, Brain Bites that explain common questions people have about air and space travel, a lunar landing simulator, and Dynamic Planet, a hands-on interactive that allows you to explore the Earth, Sun, and Solar System. Additional workstations include glove-box activities, a planetary gravity demonstrator, and a solar system scale where visitors can find out how much they would weigh on the moon and each of the planets. A display case features models that keep the learning in three dimensions.”

The exhibit tents included educational exhibits about NASA and space exploration, with NASA staff to help explain NASA projects. Most of these educational exhibit tents provided the public with NASA posters, space photographs, science-themed postcards, pins, and stickers as well as NASA hand-outs with educational activities for children, other educational hand-outs, and informational hand-outs regarding the research being conducted at the NASA Glenn Research Center, all free-of-charge. Some children were quite interested in the NASA posters.

Of course, the focal point of all of these activities was the Total Solar Eclipse / Total Eclipse of the Sun, which would pass over this site on Monday Afternoon, April 8. On the morning of April 8, weather was iffy. Clouds and some drizzle and rain occurred in the early morning hours. However, as meteorologists had predicted, the sky started clearing around 10:00 in the morning, and the rest of the day was sunny, except of course for the ~four minutes of the Totality Phase of the Total Solar Eclipse.

NASA provided free-of-charge Solar Eclipse Glasses to everyone. So, when the Solar Eclipse began at 1:59:22 p.m. EDT / 17:59:22 UTC, people put on their Solar Eclipse Glasses as they started watching the Moon slowly obscure the light from the Sun (NASA Television had started live coverage at 1:00 p.m. EDT / 17:00 UTC). More attention was payed to the sky as the Totality Phase grew closer.

A loud roar from the thousands in attendance at the event came with the beginning of the Totality Phase at 3:13:46 p.m. EDT / 19:13:46 UTC. During Totality, the outdoor temperature was briefly cooler, and the area became dark, similar to dusk, as street-lights came on. This was the only time people could safely remove their Solar Eclipse Glasses, but only for the 3 minutes and 49 seconds of Totality. Along with the Solar Corona, the Sun's upper atmosphere, seen around the edge of the Moon, the planet Venus was visible near the Eclipsed Sun.

The maximum of Totality for the 3-minute, 49-second event came at 3:15 p.m. EDT / 19:15 UTC, with the Totality Phase ending at 3:17:35 p.m. EDT / 19:17:35 UTC. The Great Lakes Science Center temporarily closed during Totality, so the Science Center staff could view the Total Solar Eclipse.

After the end of Totality, people had to put Solar Eclipse Glasses back on to see the rest of the Solar Eclipse, as the Moon began to move away and expose more and more of the surface of the Sun. The entire Solar Eclipse ended at 4:29:00 p.m. EDT / 20:29:00 UTC.  In Cleveland, the entire Solar Eclipse lasted 2 hours and 30 minutes.

This event was well attended by thousands of people from throughout the Northeastern Ohio area, as well as some people coming from Western Pennsylvania and other states including Connecticut, Georgia, and Florida. As can be expected in today's world, people entering the special event area needed to go through a metal detector and have their bags inspected.

To reach the event, many people used RTA Rapid Transit, to avoid parking problems near the Great Lakes Science Center. For Cleveland's Bicentennial in 1996, the Greater Cleveland Regional Transit Authority (RTA) opened a 2.2-mile Light Rail Rapid Transit Line from Tower City (Cleveland's Downtown Subway Hub Station, located below the historic Terminal Tower building) to the lake-front. This includes the North Coast Harbor rail station near the Great Lakes Science Center. This rail line operates mostly during special events and sometimes on weekends. For the Total Solar Eclipse event at the Great Lakes Science Center, this rail line ran from 9:30 a.m. to 5:27 p.m. Eastern Daylight Saving Time (EDT) / 13:30 to 21:27 UTC.

As with many special events, people were able to purchase T-shirts commemorating the April 8 Total Solar Eclipse. Non-profit Vitalant, which collects blood from volunteer donors and provides blood and blood products to hospitals across the country, provided free-of-charge Solar Eclipse Glasses and commemorative T-shirts to people who donated blood between March 3 and 16.

In addition to live Eclipse coverage by NASA Television, several mobile television trucks were on-site, including from a couple Cleveland television stations: WKYC-TV 3 (NBC) and WEWS-TV 5 (ABC). The event was also attended by Jeff Mason, White House Correspondent for the Reuters Wire Service.

Additionally, a film crew from the IMAX Corporation filmed the event for a future IMAX film.

At the end of the event and when the Great Lakes Science Center was closing at 5:00 p.m. EDT / 21:00 UTC, one more event for people interested in astronomy occurred in the Science Center's Cleveland Clinic Dome Theater (Omnimax theater). A screening of the world premiere of the documentary film, “Small Town Universe”, was a presentation of the 48th Annual Cleveland International Film Festival. This film, free-of-charge to the general public, documented the National Radio Astronomy Observatory in Green Bank, West Virginia and the recent controversy when the National Science Foundation considered defunding the Observatory; fortunately, it was not defunded. Following the film, there was a question-and-answer session with the film's director, Katie Dellamagiorre, and several people profiled in the film, including the featured subject, Ellie White.

Originally, the NASA Glenn Research Center's Visitors' Center was located on the campus of the research center, which is located close to the Cleveland Hopkins International Airport. In the early 1990s, NASA considered expanding the size of this Visitors' Center. At this time, the Buhl Science Center in Pittsburgh was in the process of planning construction of a new science center building on the North Shore of the Ohio River, which became The Carnegie Science Center in 1991; due to a recent $65 million donation, this building will soon be renamed the Daniel G. and Carole L. Kamin Science Center.

So, several NASA Visitors' Center staff members visited the Buhl Science Center, to learn more about the Pittsburgh expansion project. The author, Glenn A. Walsh, gave some of these staff members a tour of the Buhl Science Center's Third Floor Observatory, including the historic 10-inch Siderostat-type Refractor Telescope. Eventually, NASA decided not to expand the Visitors' Center on-site, but rather to incorporate the Visitors' Center within the Great Lakes Science Center in 2010.

This Total Solar Eclipse, viewed at the Great Lakes Science Center / NASA Visitors' Center, was attended by Friends of the Zeiss members Lynne S. Walsh, Jim McKee, and Glenn A. Walsh. Friends of the Zeiss is a non-profit organization with a mission which supports public education of astronomy, space sciences, and other sciences. The organization also promotes the history and preservation of the historic equipment, artifacts, and building of Pittsburgh's original Buhl Planetarium and Institute of Popular Science / Buhl Science Center.

Thirty years ago, another Solar Eclipse traversed the United States in a path similar to the path of the 2024 April 8 Total Solar Eclipse. On 1994 May 10, an Annular Solar Eclipse / Annular Eclipse of the Sun, which was precluded from being a Total Solar Eclipse because the Moon was farther from Earth than usual (and, hence, appeared too small to completely cover all of the surface of the Sun), also passed over Cleveland and Erie, Pennsylvania.

During an Annular Solar Eclipse, the Moon covers most of the surface of the Sun, but a small sliver of the surface of the Sun (the Annulus or “Ring of Fire”), which circles the Moon, is still visible. Hence, there is no time when it is safe to view an Annular Solar Eclipse without Solar Eclipse Glasses or other eye protection methods.

Friends of the Zeiss Steering Committee members John D. Weinhold and Glenn A. Walsh viewed this Annular Solar Eclipse, with many others, at the Mercyhurst University Observatory in the Borough of North East, Erie County, Pennsylvania. While the Mercyhurst University Observatory was located within the path of the Annular Solar Eclipse (Path of Annularity), on-site observations confirmed that the center line of the Eclipse was actually in the middle of Lake Erie.

Today, June 8, also marks the 20th anniversary of the first of two rare Transits of the Planet Venus across the Sun in the 21st century. Friends of the Zeiss sponsored the only public viewing event of the 2004 June 8 Transit of Venus within the City of Pittsburgh (from the Mount Washington Observation Deck of The Duquesne Incline).

Internet Links to Additional Information ---

Solar Eclipse / Eclipse of the Sun: Tips for Safe Viewing:

Link >>> https://buhlplanetarium2.tripod.com/FAQ/soleclipse/solareclipseviewingtips.html

ADDENDUM: Photographs - All stages of 2024 April 8 Total Solar Eclipse / Total Eclipse of the Sun, as well as events and exhibits by NASA, at the Total Eclipse Fest 2024 in Cleveland, can be found at the following Internet link:

Link >>> https://buhlplanetarium4.tripod.com/eclipse/solar/total/cleveland/NASA2024.html

NASA Total Eclipse Fest 2024, Cleveland, Map of NASA Village Tents and Topics:

Link >>> https://www.nasa.gov/wp-content/uploads/2024/04/ps-04299-nasa-village-map-final-508.pdf?emrc=345a8e?emrc=345a8e?emrc=345a8e

Annular Solar Eclipse of 1994 May 10 -

Link 1 (Cleveland): >>> https://theskylive.com/solar-eclipse?id=1994-05-10&geoid=5150529

Link 2 (Erie): >>> https://www.goerie.com/story/news/local/2023/06/07/solar-eclipse-erie-pa-may-1994-path-of-annularity-2024-path-of-totality/70278210007/

Apollo 15 Astronaut & Pittsburgh Native James Irwin:

Link >>> https://buhlplanetarium2.tripod.com/bio/Pghastronauts.html#irwin

NASA VIPER Moon Rover to be Launched on Pittsburgh's Astrobotic Griffin Lander:

Link >>> https://en.wikipedia.org/wiki/VIPER_(rover)

Related Blog-Posts ---

"U.S. Solar Eclipse April 8: Prepare for Safe Viewing." Mon. 2024 March 18.



"Great American Solar Eclipse Next Monday: Some Ways to See It Safely." Mon. 2017 Aug. 14.


"Public Observing Session of Transit of Venus Across Image of Sun, Pittsburgh - 2004 June 8." (2024 June 8: 20th Anniversary}

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

               "Photos: Total Solar Eclipse Viewed in Cleveland"

                  Saturday, 2024 June 8.

            Artificial Intelligence not used in the writing or production of this article.

            © Copyright 2024 Glenn A. Walsh, All Rights Reserved

                             Like This Post? Please Share!

More Astronomy & Science News - SpaceWatchtower 'X' / 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, Informal Science Educator & Communicator                                                             (For more than 50 years! - Since Monday Morning, 1972 June 12):
Link >>> http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/
Electronic Mail: < gawalsh@planetarium.cc >
Project Director, Friends of the Zeiss: Link >>> http://buhlplanetarium.tripod.com/fotz/
SpaceWatchtower Editor / Author: Link >>> http://spacewatchtower.blogspot.com/
Formerly Astronomical Observatory Coordinator & Planetarium Lecturer, original Buhl Planetarium & Institute of Popular Science (a.k.a. Buhl Science Center), America's fifth major planetarium and Pittsburgh's science & technology museum from 1939 to 1991.
Formerly Trustee, Andrew Carnegie Free Library and Music Hall, Pittsburgh suburb of Carnegie, Pennsylvania, the fourth of only five libraries where both construction and endowment funded by famous industrialist & philanthropist Andrew Carnegie.
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh: Link >>> http://www.planetarium.cc Buhl Observatory: Link >>> http://spacewatchtower.blogspot.com/2016/11/75th-anniversary-americas-5th-public.html
* Adler Planetarium, Chicago: Link >>> http://adlerplanetarium.tripod.com
* Astronomer, Educator, Optician John A. Brashear: Link >>> http://johnbrashear.tripod.com
* Andrew Carnegie & Carnegie Libraries: Link >>> http://www.andrewcarnegie.cc

 * Other Walsh-Authored Blog & Web-Sites: Link >>> https://buhlplanetarium.tripod.com/gawweb.html

Wednesday, May 15, 2024

Northern Lights Seen in Pittsburgh

This photograph of the Aurora Borealis, also known as the Northern Lights, was taken by Pittsburgh-area Free-Lance Photographer Lynne S. Walsh. The photograph was taken using an Apple I-Phone 12-Mini camera, from the Pittsburgh suburb of Whitehall, Pennsylvania near the Caste Village Shopping Center. While the Aurora was quite evident using the camera, it was barely visible to the naked-eyes.

More Aurora Photographs from Friends of the Zeiss members Ms. Walsh and Jim McKee:

Link >>> https://buhlplanetarium.tripod.com/aurora/2024may10/index.html

By Glenn A. Walsh

Reporting for SpaceWatchtower

Due to a major storm on the Earth's Sun, people in the Pittsburgh Metropolitan Area had a rare opportunity to see the Northern Lights, also known as the Aurora Borealis, late on Friday night (2024 May 10). Pittsburgh is just 75 miles / 120.7 kilometers north of the Mason and Dixon Line, the traditional boundary between the North and the South sections of the United States, which was created with the assistance of astronomical observations.

A Coronal Mass Ejection (CME) on the Sun, on May 10, sparked the largest Geomagnetic Storm on the Earth since Halloween of 2003. The Space Weather Prediction Center observed a G5 (greatest level of severity) extreme Geomagnetic Storm at 2:54 a.m. Eastern Daylight Saving Time (EDT) / 6:54 Coordinated Universal Time (UTC) on Friday.

The Space Weather Prediction Center (SWPC - until 2007, known as the Space Environment Center - SEC), is a division of the National Weather Service (NWS) which is part of the National Oceanic and Atmospheric Administration (NOAA), U.S. Department of Commerce.

An X3.98 Solar Flare came from colossal-sized Sunspot AR3664 on the surface of the Sun. According to a Social Media post on 'X' / Twitter, solar physicist Keith Strong wrote that the X3.98 Solar Flare is the largest from Sunspot AR3664, as well as fourth largest Solar Flare during this Solar Cycle.

This-past weekend's solar activity comes as the Sun approaches Solar Maximum during the Sun's ~11-year Solar / Sunspot Cycle, also known as the Solar Magnetic Activity Cycle or Schwabe Cycle. At Solar Maximum, the Sun's magnetic field flips, with the North Magnetic Pole becoming the South Magnetic Pole and visa-versa. After a second ~11-year Solar Cycle, the magnetic field flips again returning to the original magnetic state; this, then, completes the ~22 year Hale Cycle.

Currently, we are in Solar Cycle 25, the 25th Solar Cycle since 1755, when scientists began extensive recording of Sunspots on our Sun. Solar Cycle 25 began in December of 2019 and is expected to continue until about 2030. Additional Aurora activity may be expected over the next couple of years, as the peak of Solar Cycle 25 is expected sometime next year (perhaps around 2025 July).

Most Solar Flares and Coronal Mass Ejections, as well as other solar phenomena such as Coronal Loops and Prominences, originate in magnetically-active, large and often visible Sunspot groupings on the surface of the Sun. Sunspots are temporary spots on the Sun's surface which appear darker (usually black or gray, against the Sun's bright surface), due to the fact that Sunspots are much cooler than the rest of the Sun's surface.

The surface of the Sun, known as the Solar Photosphere, measures about +10,000 degrees Fahrenheit / +5,500 degrees Celsius. Sunspots are usually about +6,300 degrees Fahrenheit / +3,500 degrees Celsius.

Sunspots are created due to the crossing of lines of magnetic force, as the many lines of the magnetic field well-up from deep within the Sun. This occurs due to the varied rotation rates of the plasma that makes-up the Sun. On average, the Sun rotates on its axis once every 27 days. However, since the Sun is not solid, the Solar Equator only takes only about 24 days to rotate once, while the Poles take more than 30 days.

Sunspots usually come in pairs. Sunspots consist of a central darker area (black), known as the Umbra, surrounded by a lighter area (gray) known as the Penumbra.

Many Sunspots are huge. Sunspot AR3664 is estimated to be about 15 times the size of the planet Earth. At Pittsburgh's original Buhl Planetarium Observatory (1941 to 1994), using the historic 10-inch Siderostat-type Refractor Telescope, visitors could easily compare the size of a particular Sunspot with the size of the Earth; the Sun's surface would be projected from the telescope onto a large projection screen, which included an outline of the size of the planet Earth.

Astronomers have observed Star-spots, which are similar to our Sun's Sunspots, on some stars in our Milky Way Galaxy.

Solar activity such as Solar Flares and Coronal Mass Ejections (CMEs) can adversely affect radio communication [particularly long-distance (DX) High Frequency (HF) radio signals: Medium-Wave (AM band) and Short-Wave (SW)], satellites and GPS systems, and in severe cases can disrupt electrical grid systems.

Thus far, the current Geomagnetic Storm has resulted in temporary or complete loss of High Frequency radio signals across Asia, Eastern Europe, and eastern Africa; long-distance HF radio signals have also been affected in the United States. However, the U.S. Department of Energy has reported that the Geomagnetic Storm has had no impact on infrastructure that affects customers.

The 2003 October Geomagnetic Storm resulted in power outages in Sweden and damaged power transformers in South Africa. In March of 1989, a Geomagnetic Storm caused power failures over large sections of the Canadian province of Quebec, while less severe storms occurred in 1921 and 1960 when there were widespread reports of radio disruptions.

However, the largest effects felt on Earth occurred, at the very beginning of the electrical age, in the first couple of days of September of 1859, when ground-based magnetometers recorded one of the largest Geomagnetic Storms ever. This is known as the "Carrington Event" for English Amateur Astronomer Richard Carrington, who made among the first observations of a major Solar Flare on September 1 that is associated with a huge CME that led to telegraph system failures, electric shocks to telegraph operators, and even fires in some telegraph offices. The Carrington Event also resulted in Aurora observations throughout the world, particularly in lower latitude locations unaccustomed to such displays.

In April of 2014, NASA announced that an event possibly similar to the Carrington Event may have missed the Earth in 2012. On 2012 July 23, NASA's STEREO-A spacecraft recorded a huge CME that sped four times faster from the Sun than a normal solar eruption. Fortunately, the Earth was not in the path of this CME, which Daniel Baker of the University of Colorado claimed "might have been stronger than the Carrington Event itself".

Friends of the Zeiss is a non-profit organization with a mission which supports public education of astronomy, space sciences, and other sciences. The organization also promotes the history and preservation of the historic equipment, artifacts, and building of Pittsburgh's original Buhl Planetarium and Institute of Popular Science / Buhl Science Center.

Internet Links to Additional Information ---

ADDENDUM: Aurora Photographs from Friends of the Zeiss members Lynne S. Walsh and Jim McKee:

Link >>> https://buhlplanetarium.tripod.com/aurora/2024may10/index.html

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

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

Solar Flare: Link >>> https://en.wikipedia.org/wiki/Solar_flare

Coronal Mass Ejection (CME): Link >>> https://en.wikipedia.org/wiki/Coronal_mass_ejection

Solar Cycle: Link >>> https://en.wikipedia.org/wiki/Solar_cycle

Solar Cycle 25: Link >>> https://en.wikipedia.org/wiki/Solar_cycle_25

Carrington Event: Link >>> https://en.wikipedia.org/wiki/Carrington_Event

Related Blog-Posts ---

"250th Anniversary: Astronomy Helps Create Mason-Dixon Line." Wed. 2017 Oct. 18.


"Largest Sunspot in 24 Years Returns for 2nd Month." Sun., 2014 Nov. 23.

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

               "Northern Lights Seen in Pittsburgh"

                  Wednesday, 2024 May 15.

            Artificial Intelligence not used in the writing or production of this article.

            © Copyright 2024 Glenn A. Walsh, All Rights Reserved

                             Like This Post? Please Share!

More Astronomy & Science News - SpaceWatchtower 'X' / 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, Informal Science Educator & Communicator                                                             (For more than 50 years! - Since Monday Morning, 1972 June 12):
Link >>> http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/
Electronic Mail: < gawalsh@planetarium.cc >
Project Director, Friends of the Zeiss: Link >>> http://buhlplanetarium.tripod.com/fotz/
SpaceWatchtower Editor / Author: Link >>> http://spacewatchtower.blogspot.com/
Formerly Astronomical Observatory Coordinator & Planetarium Lecturer, original Buhl Planetarium & Institute of Popular Science (a.k.a. Buhl Science Center), America's fifth major planetarium and Pittsburgh's science & technology museum from 1939 to 1991.
Formerly Trustee, Andrew Carnegie Free Library and Music Hall, Pittsburgh suburb of Carnegie, Pennsylvania, the fourth of only five libraries where both construction and endowment funded by famous industrialist & philanthropist Andrew Carnegie.
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh: Link >>> http://www.planetarium.cc Buhl Observatory: Link >>> http://spacewatchtower.blogspot.com/2016/11/75th-anniversary-americas-5th-public.html
* Adler Planetarium, Chicago: Link >>> http://adlerplanetarium.tripod.com
* Astronomer, Educator, Optician John A. Brashear: Link >>> http://johnbrashear.tripod.com
* Andrew Carnegie & Carnegie Libraries: Link >>> http://www.andrewcarnegie.cc

 * Other Walsh-Authored Blog & Web-Sites: Link >>> https://buhlplanetarium.tripod.com/gawweb.html