SpaceWatchtower

Friday, September 20, 2024

Fall Begins at Equinox Sunday Morning

This diagram shows the position of the Earth, in relation to the Sun, at the time of the Autumnal Equinox, as well as the other equinox and solstices of the year.

[Graphic Source: ©1999, Eric G. Canali, former Floor Operations Manager of the original Buhl Planetarium and Institute of Popular Science / Buhl Science Center (America's 5th major planetarium & Pittsburgh's science and technology museum from 1939 to 1991) and Founder of the South Hills Backyard Astronomers amateur astronomy club. Permission granted for non-profit use only, with credit to author.]

By Glenn A. Walsh

Reporting for SpaceWatchtower

The Autumnal Equinox Sunday morning marks the end of the season of Summer and the beginning of Fall or Autumn in Earth's Northern Hemisphere. In the Southern Hemisphere, this marks the transition from Winter to Spring.

The Autumnal Equinox (also known as the September Equinox), the end of Summer and the beginning of the season of Autumn or Fall in Earth's Northern Hemisphere, occurs Sunday Morning, 2024 September 22 at 8:44 a.m. Eastern Daylight Saving Time (EDT) / 12:44 Coordinated Universal Time (UTC). In the Southern Hemisphere, this moment marks the astronomical beginning of the season of Spring.

Autumn or Fall continues in the Northern Hemisphere, and Spring in the Southern Hemisphere, until the December Solstice: Saturday Morning, 2024 December 21 at 4:21 a.m. Eastern Standard Time (EST) / 9:21 UTC. At the moment of the December Solstice, Winter begins in the Northern Hemisphere and Summer begins in the Southern Hemisphere.

The approximate and traditional mid-way point between the Autumnal Equinox and the Winter Solstice comes in the vicinity of October 31 (All-Hallows Eve or Halloween) / November 1 (All-Saints Day) / November 2 (All-Souls Day): the Astronomical Cross-Quarter Day of Samhain or All-Hallowsmas. The actual November Cross-Quarter Day will be Wednesday Afternoon, 2024 November 6 at .5:21 p.m. EST / 22:21 UTC. The approximate one-week discrepancy between the dates of the traditional and actual Cross-Quarter Day is due to the fact that the traditional date of Samhain was fixed on October 31, when the Julian Calendar was still in use.

In ancient times, a calendar season was considered the time between one Cross-Quarter Day and the next Cross-Quarter Day. So, Autumn was considered the time between August 1 (Lughnasadh or Lammas Day), which was the traditional beginning of the wheat harvest, to October 31 (Samhain). Samhain actually means “Summer's end” as the Celtic calendar only considered two main seasons: Summer and Winter.

The Celtic peoples of Ireland began celebrations on Samhain in the 5^th century B.C. Samhain was considered by the Celtics and Druids on the British Isles as the end of the old year, with the following day the beginning of the New Year. In A.D, 835, the Roman Catholic Church named November 1 All-Saints Day with the previous day becoming All-Hallows Eve or Halloween, the eve or evening before All-Saints Day.

It is believed that in ancient times the Pleiades Star Cluster, also known as the Seven Sisters, culminated (climbed to the cluster's highest point in the sky) around Midnight local time on or near Samhain. Samhain and Pleiades Culmination would have occurred together around A.D. 11^th and 12^th centuries before the Gregorian Calendar was instituted. For the Pleiades Culmination to occur during the dark time of the year's end, many peoples felt this was a time to honor the dead. Although today Pleiades Culmination occurs on November 21, the Pleiades still can be seen high in the sky around local Midnight on Halloween, weather-permitting.

On the day of the Equinox, the Sun appears directly overhead at local Noon on the Equator. At the moment of Equinox, the Northern and Southern Hemispheres of Earth are illuminated equally. And, the time of Equinox is the only time when the Earth Terminator (dividing line on Earth between daylight and darkness) is perpendicular to the Equator.

This, and the reason for seasons on Earth in the first place, is due to the fact that Earth rotates on its axis, which is tilted at an approximate 23.44-degree angle from the Ecliptic, the plane of the Earth's orbit around the Sun. As the Earth revolves around the Sun, this axial tilt causes one hemisphere of the planet to receive more direct solar radiation during that hemisphere's season of Summer and much less direct solar radiation about a half-year later during that hemisphere's season of Winter. As mentioned, during an Equinox [in the Northern Hemisphere: about half-way between Summer and Winter (Autumnal Equinox), and about half-way between Winter and Summer (Vernal Equinox)] both planetary hemispheres receive an equal amount of solar radiation.

Although "Equinox" in Latin means equal-night, the day of the Equinox does not actually have an equal amount of daylight and nightfall, as it appears on the Earth's surface. If the Sun was just a pin-point of light in our sky, as all other stars appear, day and night would be equal.

But, because the Sun is a disk, part of the Sun has risen above the horizon before the center of the Sun (which would be the pin-point of light); so there are extra moments of light on the Equinox. Likewise, part of the Sun is still visible, after the center of the Sun has set.

Additionally, the refraction of sunlight by our atmosphere causes sunlight to appear above the horizon, before sunrise and after sunset.

Each year, September 25 or 26 marks the Equilux ("equal-light"), the actual day with equal hours and minutes of the Sun above the horizon, and equal hours and minutes of the Sun below the horizon. The Equilux occurs twice each year, approximately 3-to-4 days before the Vernal Equinox, when Spring begins, and 3-to-4 days after the Autumnal Equinox, after Autumn or Fall has begun.

An urban legend that has been making the rounds for decades has it that eggs can be stood on their ends only during an Equinox, whether the Vernal Equinox in the Spring or the Autumnal Equinox in the Fall. This is completely false. Depending greatly on the size and shape of the particular egg, eggs can be stood on their ends any day of the year! Astronomy has nothing to do with whether an egg can stand on its end. If an egg can stand on its end on the Equinox (and, due to the shape and size of some eggs, this is not even possible), it can stand the same way any other day of the year.

In the last few years, with the help of the Internet and Social Media, another urban legend has become prevalent. Now it is claimed that brooms can stand, on their own, on their bristles, only on an Equinox day. This is also false. Again, as with eggs, if a broom can stand on its bristles by itself (this usually only works with newer brooms, with more stiff and even bristles) on an Equinox, it can do so any day of the year!

In China, Vietnam, Korea, Japan, and other nations in East and Southeast Asia, a popular harvest festival is celebrated on the date close to the Autumnal Equinox of the Solar Cycle, as well as close to the Harvest Moon. This Mid-Autumn Festival / Moon Festival dates back more than 3,000 years to Moon worship in China's Shang Dynasty.

Again, as Western Cultures consider September the beginning of Autumn (meteorologists and climatologists consider September 1 the beginning of Meteorological Autumn), the ancients often termed this as "Mid-Autumn". By this reckoning, Autumn actually began at the traditional Cross-Quarter Day of August 1 (when some harvesting actually begins) and ends at the traditional Cross-Quarter Day of All-Hallow's Eve, also known as Halloween.

On the Chinese Han Calendar, the Mid-Autumn Festival falls on the 15th day of the 8th month (on a day between September 8 and October 7 in our Gregorian Calendar). This usually falls on the night of a Full Moon, the Harvest Moon. This year, the Harvest Moon occurred on Tuesday Evening, 2024 September 17 at 10:34 p.m. EDT / September 18, 2:34 UTC. This particular Harvest Moon was also a so-called “Super-Moon” (Lunar Perigee Full Moon), which experienced a shallow Partial Lunar Eclipse / Partial Eclipse of the Moon.

September 22 is designated as Falls Prevention Awareness Day.

Internet Links to Additional Information ---

Mid-Autumn Festival / Moon Festival: Link >>> https://en.wikipedia.org/wiki/Mid-Autumn_Festival

Cross-Quarter Day: Link >>> https://en.wikipedia.org/wiki/Wheel_of_the_Year

Autumnal Equinox: Link >>> http://scienceworld.wolfram.com/astronomy/AutumnalEquinox.html

Season of Autumn or Fall: Link >>> http://en.wikipedia.org/wiki/Autumn

Equinox: Link >>> http://en.wikipedia.org/wiki/Equinox

Equilux: Link >>> https://darkskydiary.wordpress.com/2010/03/20/equinox-equilux-and-twilight-times/

Earth's Seasons: Link >>> http://en.wikipedia.org/wiki/Season

Tilt of a planet's axis: Link >>> http://en.wikipedia.org/wiki/Axial_tilt

Urban legend of eggs and brooms standing on their own, only on an Equinox:
Link >>> http://www.snopes.com/science/equinox.asp

Falls Prevention Awareness Day: Link >>> https://nationaltoday.com/falls-prevention-awareness-day

Why Autumn Leaves Change Color: Link >>> http://spacewatchtower.blogspot.com/2013/10/colorful-fall-foliage-astronomy-affects.html

Related Blog-Post ---

"Partial Eclipse of Harvest Moon Tue. Night". Fri., 2024 Sept. 13.

Link >>> https://spacewatchtower.blogspot.com/2024/09/partial-eclipse-of-harvest-moon.html

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

"Fall Begins at Equinox Sunday Morning"

Friday, 2024 September 20.

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

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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

Friday, September 13, 2024

Partial Eclipse of Harvest Moon Tue. Night

The Harvest Moon often appears orange in color due to Rayleigh Scattering of sunlight from the Moon, which occurs whenever the Moon is near the horizon. The Harvest Moon always rises around the time of local sunset. (Image Sources: Wikipedia.org, By The original uploader was Roadcrusher at English Wikipedia. - Transferred from en.wikipedia to Commons by Khayman using CommonsHelper., CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=15755496)

By Glenn A. Walsh

Reporting for SpaceWatchtower

Tuesday evening, the Full Harvest Moon (which some would call the second so-called “Super-Moon” of 2024) comes with a bonus – a Partial Lunar Eclipse / Partial Eclipse of the Moon, which will be visible in most of the Western Hemisphere, Europe, Africa, and the Middle East. However, this Eclipse, which is safe to watch directly (weather-permitting), will be a very slight or shallow Lunar Eclipse.

Partial Lunar Eclipse / Partial Eclipse of the Moon

A Lunar Eclipse / Eclipse of the Moon is the only category of eclipses which is safe to view with the unaided eyes (one-power), binoculars, and a telescope.

A Live-stream Web-cast of this Partial Lunar Eclipse / Partial Eclipse of the Moon will be available for observers not in a region where the eclipse is visible in the sky, or where weather conditions make such an observation impossible (Internet link to this Live-stream near the end of this blog-post).

Everyone on the night or dark side of the Earth can view at least part of any Lunar Eclipse / Eclipse of the Moon, weather-permitting. People located where weather blocks direct view of the Eclipse, or who live in other parts of the world, would need to watch the eclipse on the Internet.

Here are the major stages of this Partial Lunar Eclipse / Partial Eclipse of the Moon –--

Late Tuesday Evening, 2024 September 17 / Wednesday Morning, 2024 September 18 -

[Eastern Daylight Saving Time (EDT) / Coordinated Universal Time (UTC)]

(Note that a Lunar Eclipse / Eclipse of the Moon is the only type of Eclipse where the times of Eclipse are the same world-wide, when using Coordinated Universal Time. Everyone on the dark or night side of Earth can view this Eclipse in the sky, weather-permitting.)

Penumbral Lunar Eclipse Begins --- Sept. 17, 8:41:07 p.m. EDT / Sept. 18, 0:41:07 UTC

Partial Lunar Eclipse Begins --- Sept. 17, 10:12:58 p.m. EDT / Sept. 18, 2:12:58 UTC

Primary Moon Phase: Full Moon – Harvest Moon --- Sept. 17, 10:34 p.m. EDT / Sept. 18, 2:34 UTC

Greatest Partial Lunar Eclipse --- Sept. 17, 10:44:18 a.m. EDT / Sept. 18, 2:44:18 UTC

Partial Lunar Eclipse Ends --- Sept. 17, 11:15:38 p.m. EDT / Sept. 18, 3:15:38 UTC

Penumbral Lunar Eclipse Ends --- Sept. 18, 12:47:27 a.m. EDT / Sept. 18, 4:47:27 UTC

At the time of Greatest Partial Lunar Eclipse / Partial Eclipse of the Moon on September 17, the Moon will be only 3.5 per-cent obscured by the Earth's Umbral shadow. The remaining portion of the Moon's surface will be well within the Penumbral shadow of the Earth. At this time, the Moon will appear as if a small chip, in the upper right portion of the Moon, has been removed, while the rest of the Moon may appear a wee-bit dimmer than normal. Thus, this a very shallow Partial Lunar Eclipse / Partial Eclipse of the Moon.

And, the bright object near the Moon during this Eclipse will be the ringed-planet Saturn.

A Lunar Eclipse / Eclipse of the Moon occurs when the orbit of the Moon brings our natural satellite into the Earth's shadow (shadow caused by the Earth completely blocking light from the Sun). The Earth's shadow, extending into Outer Space from the dark or night side of Earth, is divided into two sections: the dim Penumbra or Penumbral shadow, which encircles the deeper Umbra or Umbral shadow. The Moon's orbit is slightly tilted, so most months at the primary Moon phase of Full Moon, the Moon moves above or below the Earth's shadow, with no Eclipse occurring.

A Lunar Eclipse / Eclipse of the Moon always occurs near the time, and including the time, of a Full Moon. Many Native Americans called the Full Moon of November the Corn Moon or Barley Moon in addition to being known to European and American farmers as the Harvest Moon, but, more on that later.

When the Earth's dim shadow, known as the Penumbra, falls on the Moon, it is called a Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon. Because the Earth's shadow is dim in this case, this type of Eclipse is difficult to discern.

When the Earth's deep shadow, known as the Umbra, falls on only part of the Moon's surface, this is known as a Partial Lunar Eclipse / Partial Eclipse of the Moon. This is more easily visible, if you are in the right location and weather conditions are acceptable.

A Total Lunar Eclipse / Total Eclipse of the Moon is when the Earth's deep shadow, or Umbra, completely envelops the Moon. Usually, a Total Lunar Eclipse / Total Eclipse of the Moon only occurs once every 2.5 years, approximately, as seen from someplace in the world. The last one was seen in North America on 2022 May 15 / 16.

Of course, "Totality" / Total Phase of a Total Lunar Eclipse / Total Eclipse of the Moon is the most impressive part of this type of Eclipse, what most people wait to see. The Partial Phases of the Eclipse are when a piece of the Moon seems missing, as the Moon moves further into the Earth's main shadow known as the Umbra, or as the Eclipse is ending and the Moon is further moving out of the Earth's Umbra.

The Penumbral Phases of the Eclipse are difficult to see, as the Moon moves into or out of the Earth's secondary shadow or Penumbra. In this case, one would not see any chunks or bites taken out of the Moon's disk, as one would see when the Moon moves into the Umbra shadow during the Partial Phases. Instead, if your eyes are very good, you may notice a slight dimming of the light coming from the Moon, as the Moon moves further into the Penumbral shadow

Although no direct sunlight reaches the Moon during a Total Lunar Eclipse / Total Eclipse of the Moon, the Earth's atmosphere refracts the sunlight around our planet allowing a portion of the sunlight to continue to be transmitted to the Moon. However, the refracted light reaching the Moon is primarily in the yellow, orange, and red portions of the electromagnetic spectrum (the Earth's atmosphere filters-out the violet, blue, and green colors), as with orange or red-tinted sunrises and sunsets (during such a Total Lunar Eclipse / Total Eclipse of the Moon, a person standing on the side of the Moon facing Earth could see all Earth sunrises and sunsets simultaneously, as they viewed the Earth in a Total Solar Eclipse / Total Eclipse of the Sun --- but, even on the Moon, a person would need to take strong precautions to ensure their eye-sight is not damaged by such a view). Hence, it is orange or red light that is reflected from the Moon back into your eyes during a Total Lunar Eclipse / Total Eclipse of the Moon.

Hence, particularly during the middle of a Total Lunar Eclipse / Total Eclipse of the Moon, the Moon will not disappear from view but can be seen with an orange or reddish tint, what some call "blood red" (this is sometimes referred to as a “Blood Moon”). If the Earth had no atmosphere, likely no sunlight would reach the Moon during a Total Lunar Eclipse / Total Eclipse of the Moon, and there would be no "Blood Moon;" the Moon would seem to completely disappear.

Harvest Moon

More evening light, coming just after the earlier sunsets of late Summer and early Autumn, occur with the Harvest Moon (the Full Moon of September) and a few days near the day of this Full Moon (weather-permitting). Traditionally, this time of year helped give farmers more light in the evening as they work to harvest their crops before the coming Winter. However, anyone can take advantage of this extra evening light, as the early Autumn evenings continue with moderate temperatures.

For this year, the Harvest Moon will be the Full Moon of Tuesday Evening, 2024 September 17, at 10:34 p.m. Eastern Daylight Saving Time (EDT) / September 18, 2:34 Coordinated Universal Time (UTC). Of course, the Harvest Moon becomes visible (weather-permitting) in the vicinity of the time of sunset on the days around the day of Full Moon.

For farmers eager to finish harvesting their crops, the bright Full Moon which shines on their farms for the several evenings closest to the Autumnal Equinox is called the Harvest Moon. This year the Autumnal Equinox, the beginning of the season of Autumn or Fall in the Earth's Northern Hemisphere and the beginning of the season of Spring in the Southern Hemisphere, will occur on Sunday Morning, 2024 September 23 at 8:44 a.m. EDT / 12:44 UTC.

The Harvest Moon is one of the signature astronomical events shortly before the beginning of, or shortly after the beginning of, the Fall season. It is an event particularly anticipated by farmers of both the past and the present. As many crops reach the time of harvest in late Summer and early Autumn, often the work of the harvest has to continue past sunset, which comes earlier and earlier each evening.

Nature has come to the rescue of these farmers, with a bright Full Moon (weather-permitting), which arrives just around the time of sunset, that allows farmers and their staff to continue the harvest after the Sun's direct light has dissipated. Hence, long-ago this Full Moon came to be known as the Harvest Moon.

For a similar reason, the Full Moon of October is often known as the Hunter's Moon, which allowed Native Americans to continue the hunt after sunset, to begin to store meat for the coming Winter months. However, the Harvest Moon is designated as the closest Full Moon to the Autumnal Equinox, and such a Full Moon does not always occur in September. Every few years the Harvest Moon occurs in October, shortly after the Autumnal Equinox. During those years, the Hunter's Moon occurs in November.

This year, the Hunter's Moon occurs on Thursday Morning, 2024 October 17 at 7:26 a.m. EDT / 11:26 UTC. Of course, the Hunter's Moon becomes visible (weather-permitting) in the vicinity of the time of sunset on the days around the day of Full Moon. This year's Hunter's Moon will be another so-called “Super-Moon” (the third of four so-called “Super-Moons” in 2024), being the largest Full Moon of 2024.

On average, the Moon rises about 50 minutes later each day. However, during the days near the Autumnal Equinox, the Moon rises each day only about 25-to-35 minutes later each day in the U.S.A., and only 10-to-20 minutes later each day in much of Canada and Europe. Thus, for several days around the time of the Autumnal Equinox, the Harvest Moon appears to rise around the same time each evening (roughly coinciding with local sunset), providing light at the time most needed by farmers.

The reason for this is due to the Ecliptic, the apparent path of the Sun, Moon, and planets through Earth's sky, which makes a narrow angle with the horizon this time of year. It is this narrow angle which provides that moonrise occurs around the time of sunset, near the time of the Full Moon of September (for the Harvest Moon) and near the time of the Full Moon of October (for the Hunter's Moon). Hence, several evenings (before darkness has fallen) appear to have a rising Full Moon.

Also, at this time of year when farmers need moonlight the most, the Harvest Moon appears larger and more prominent, due to the mysterious but well-known "Moon Illusion" that makes the Moon seem larger when it is near the horizon. And, while near the horizon, the Moon is often reddened by clouds and dust, creating the appearance of a large, rising red ball.

Some even liken a rising Harvest Moon to a rising "Great Pumpkin," of Peanuts comic-strip fame! In the Peanuts' network-television cartoon just before Halloween each year (originally aired on CBS-TV on 1966 October 27) titled, "It's the Great Pumpkin, Charlie Brown", the “Great Pumpkin” rises over the pumpkin patch to provide gifts to all good little boys and girls.

Although Western Cultures consider September the beginning of Autumn (meteorologists and climatologists consider September 1 the beginning of Meteorological Autumn), the ancients often termed this as "Mid-Autumn". By this reckoning, Autumn actually began at the traditional Cross-Quarter Day of August 1 (when harvesting of wheat usually begins) and ends at the traditional Cross-Quarter Day of All-Hallow's Eve, also known as Halloween.

This year's Harvest Moon will also be a so-called "Super-Moon", the second of four in 2024. A so-called "Super-Moon" occurs when the Full Moon is closer to the Earth than average, and hence, the Moon appears a little larger than average in the sky.

The orbit of the Moon around the Earth is not a perfect circle, but an ellipse. Hence, during the near-monthly orbit of the Moon around the Earth, at one time during the month the Moon is closer to the Earth than normal (known as Lunar Perigee) and about a half-month later the Moon is farther from the Earth than normal (known as Lunar Apogee). Hence, when the Primary Moon Phase of Full Moon occurs at or near Lunar Perigee, some people refer to the slightly larger visible Full Moon as a so-called "Super-Moon".

This month's Lunar Perigee occurs about 10 hours after the Harvest Moon - Wednesday Morning, 2024 September18 at 9:00 a.m. EDT / 13:00 UTC: 222,007.228 statute miles / 357,286 kilometers distance of the Moon from Earth.

Native Americans also called the Full Moon of September the Corn Moon or Barley Moon, as Corn and Barley were among their main crops. Sometimes, the September Full Moon in the Northern Hemisphere is also known as the Fruit Moon. Other Full Moon names for September include Chrysanthemum Moon (China), Singing Moon (Celtic), Nut Moon (American Indian - Cherokee), Mulberry Moon (American Indian - Choctaw), and Moon When the Calves Grow Hair (American Indian - Dakotah Sioux).

In the Southern Hemisphere, where Winter is turning to Spring, the September Full Moon is known as the Lenten Moon, Worm Moon, Crow Moon, Sugar Moon, Chaste Moon, or Sap Moon. Another Full Moon name for September includes Storm Moon (South Africa).

The Harvest Moon in the Southern Hemisphere occurs in March or April, with the same advantages to Southern Hemisphere farmers as the Harvest Moon in the Northern Hemisphere.

Live-stream Web-cast of this Partial Lunar Eclipse / Partial Eclipse of the Moon can be found at the following Internet link --

Link >>> https://www.timeanddate.com/live/eclipse-lunar-2024-september-18

Internet Links to Additional Information ---

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

Lunar Eclipse / Eclipse of the Moon: Link >>> https://en.wikipedia.org/wiki/Lunar_eclipse

Harvest Moon: Link >>> https://en.wikipedia.org/wiki/Full_moon#Harvest_moon

Why Autumn Leaves Change Color: Link >>> http://spacewatchtower.blogspot.com/2013/10/colorful-fall-foliage-astronomy-affects.html

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

"Partial Eclipse of Harvest Moon Tue. Night"

Friday, 2024 September 13.

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

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

Monday, August 26, 2024

Odd 'Wow!' Radio Signal from Outer Space Explained ?

The wow! scribble on the computer printout

Image of the 1977 computer print-out where the 'Wow' Signal was discovered.

(Image Source: Smithsonian Magazine)

By Glenn A. Walsh

Reporting for SpaceWatchtower

Scientists have now reported a possible explanation for an odd radio signal received from Outer Space in 1977. Originally described as the 'Wow!' Signal, some considered the possibility of a radio signal broadcast from an extraterrestrial civilization. Now, a more natural explanation has been proposed.

A strong narrow-band radio signal was detected on 1977 August 15 by the Big Ear Radio Telescope on the grounds of Perkins Observatory at Ohio Wesleyan University in Delaware, Ohio. Operated by the Ohio State University from 1963 to 1998, this radio telescope was part of the university's Search for Extraterrestrial Intelligence (SETI) project.

It was astronomer Jerry Ehman who discovered, what he referred to as the 'Wow!' Signal, on a computer print-out from automated observations the previous night. This intense and narrow transmission from Outer Space had lasted at least 72 seconds. On the print-out Mr. Ehman circled in bright red ink the series of letters and numbers that represented the unusual radio transmission. Then, he wrote next to the circled letters and numbers, in the margin: Wow!

In 1994, Mr. Ehman told newspaper reporter Barry Kawa, of the Cleveland Plain Dealer, “Without thinking, I wrote ‘Wow!' It was the most significant thing we had seen.”

Scientists considered this signal so unusual, because it was so intense and had a highly specific frequency. As this signal was similar to a natural radio transmission by hydrogen (Chemical symbol: H) atoms, this suggested that it was not a normal transmission from Outer Space. Of course, some people assumed that this may be a broadcast from an alien civilization. Actually, seeking such alien transmissions was one of the primary purposes of this Big Ear Radio Telescope.

However, on August 16 three scientists proposed an alternate explanation for the 'Wow!' Signal, published in a pre-print Internet web-site for academic papers which have not yet gone through the peer-review process: arXiv. These scientists propose that the 'Wow!' Signal may have been the result of a very rare event in Outer Space: the sudden brightening of a cold hydrogen cloud. As explained in Smithsonian Magazine: the scientists “suggest a strong source of energy, such as a flare from a super-magnetized, extremely dense star called a magnetar, could have struck a cloud of hydrogen gas and caused it to glow brighter. The cloud could have emitted a laser-like beam of radiation in a phenomenon called a maser.”

Past hypotheses held that the 'Wow!' Signal came from a passing comet or a star. These, somewhat controversial, explanations were soon dismissed by most scientists.

The lead author of this new research is Abel Mendez, a planetary astrobiologist and Director of the Planetary Habitability Laboratory. His co-authors are Kevin Ortiz Ceballos of the Harvard and Smithsonian Center for Astrophysics and Jorge Zuluaga of the University of Antioquia in Colombia.

They analyzed archived data that had been collected using the huge Arecibo Observatory Radio Telescope in Puerto Rico. In 2020, this famous telescope was decommissioned and dismantled by the U.S. National Science Foundation, after the radio dish was damaged by two cable breaks which threatened the structural integrity of the support structure for the suspended platform.

This proposed explanation is not supported by all scientists. This is particularly true since the proposed explanation has never been observed in the Universe. So, the alien communication hypothesis has still not been completely dismissed.

Actually, the Search of Extraterrestrial Intelligence by radio began exactly 100 years ago, last week. It was on 1924 August 21 that, under the urging of retired Massachusetts' Amherst College Astronomy Professor David Todd, U.S. Army and Navy radio stations, as well as the general public, started listening for radio messages from the planet Mars. Several years earlier, radio pioneers Nicola Tesla and Guglielmo Marconi had reported receiving odd radio signals from Outer Space, which they thought could have come from Mars.

A century ago this-past week, Mars and Earth were closer than the two planets had been in many years. The Amherst astronomer thought this might be a time that Martians would try to contact Earth via radio.

By 1924, most scientists believed that Mars was too cold and dry to have human-like life, but not everyone else agreed. Businessman, author, and mathematician Percival Lowell, who had constructed an astronomical observatory in Flagstaff, Arizona specifically to study Mars, had publicly promoted the idea that Martians had built canals to bring water from the poles to the rest of a dying planet. Hence, the general public was enthralled with the idea of intelligent life on Mars.

One hundred years ago, Dr. Todd had asked radio stations to go silent for five minutes each hour for several nights, to make it easier to hear the radio signals from Mars; only radio station WRC in Washington DC actually did so. However, other military, commercial, and amateur radio operators still listened for the extraterrestrial signals. And, a leading military cryptographer was made available to decode any messages from Mars.

There were a lot of radio signals received during this first SETI radio search, but the signals came from Earth or natural radio sources in the Universe. No message from Mars was ever detected.

Internet Links to Additional Information ----

'Wow!, Signal: Link >>> https://en.wikipedia.org/wiki/Wow!_signal

Ohio State University Radio Observatory (former home of Big Ear Radio Telescope):

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

Arecibo Radio Telescope: Link >>> https://en.wikipedia.org/wiki/Arecibo_Telescope

Related Blog-Post ---

"50th Anniversary: Kecksburg, Pa. "UFO" Incident." Wed., 2015 Dec. 9.

Link >>> http://spacewatchtower.blogspot.com/2015/12/50th-anniversary-kecksburg-pa-ufo.html

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

"Odd 'Wow!' Radio Signal from Outer Space Explained ?"

Monday, 2024 August 26.

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

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

Friday, August 9, 2024

Best Meteor Shower of Year Late-Night Sun. & Mon.

The vast majority of meteors that are visible during meteor showers are usually quite small, even though they often make a bright spectacle when entering Earth's atmosphere. However, some meteors which actually land on Earth, sometimes creating a crater, can be quite large. The above photograph shows the fifth largest fragment of the meteorite which created Meteor Crater near Winslow, Arizona, on public display near the entrance to the Henry Buhl, Jr. Planetarium at Pittsburgh's Kamin (Carnegie) Science Center. Owned by the City of Pittsburgh, this meteorite was originally acquired for, and displayed at, the original Buhl Planetarium and Institute of Popular Science (a.k.a. Buhl Science Center), America's fifth major planetarium & Pittsburgh's science and technology museum from 1939 to 1991.

More Information: Link >>> https://buhlplanetarium2.tripod.com/Buhlexhibits.htm#meteorite

(Image Source: Friends of the Zeiss' History of Buhl Planetarium Internet Web-site)

By Glenn A. Walsh

Reporting for SpaceWatchtower

The annual Perseid Meteor Shower, which peaks late-night on Sunday and Monday, is considered the best Meteor Shower of the year by NASA and most astronomers. Meteor sightings should be optimum this year after local Midnight, as the peak of this Meteor Shower comes just a little more than an hour before the First Quarter Moon lunar phase.

Astronomically, the peak of the Perseid Meteor Shower comes this year during the late-night and early-morning hours of Sunday, Monday, and Tuesday, 2024 August 11, 12, and 13. Technically, the actual peak is predicted to occur on Monday, 2024 August 12 at 10:00 a.m. Eastern Daylight Saving Time (EDT) / 14:00 Coordinated Universal Time (UTC).

The best time to watch most Meteor Showers, including this year's Perseids, is always between local Midnight and Dawn, when the Earth is rotating into the Meteor Shower. So, the best time to view this year's Perseid Meteor Shower is late Sunday night through early Tuesday morning.

At the peak-time, sometimes up-to 50-to-100 Meteors could possibly be seen per-hour, if observing conditions are ideal. Depending on your location (including elevation and number of obstructions to sky viewing, such as hills, trees, and buildings), weather conditions, Moon phase, and the condition of your eye-sight, seeing 40-to-60 Meteors per-hour would be more likely.

As most Meteors are often dim, it is best to view a Meteor Shower away from city lights, which cause a brightening of the sky at night, and hence, the dimmest Meteors are often missed. And, you want to go out ahead of time, before you start actual viewing of Meteors, to get your eyes accustomed to the dark sky. Dark-adapting your eyes for Meteor watching could take up-to one half-hour.

Also, after your eyes are dark-adapted, do not look at your cellular telephone while looking for Meteors. The light you see from your telephone could disrupt your dark-adapted night-vision.

For the peak of the Perseid Meteor Shower this year, the Moon will be just a little more than an hour before the Primary Moon Phase of First Quarter. So, the Moon will be setting around or a little after local Midnight. Hence, the dimmer Meteors may be a little easier to find in a sky that is not brightened by much Moon-light.

The Primary Lunar Phase of First Quarter will occur on Monday, 2024 August 12 at 11:19 a.m. EDT / 15:19 UTC. In years when the Moon-light is brighter than it will be this year, try not to look directly at the Moon, so it does not hinder your dark-adapted eye-sight.

Actually, some Meteors from the Perseid Meteor Shower can be seen as early as mid-July and as late as late August (~July 17 to August 24); but they are few and far-between. Most Perseid Meteors can be seen three-to-five days before and three-to-five days after the peak time, which is considered, approximately, between August 9 and 14 each year; again, the absolute peak is August 11 to 13.

Viewers in the Northern Hemisphere are fortunate that the Perseid Meteor Shower arrives during the Summer month of August, when temperatures are comfortable for night-time viewing. However, some locations (such as in the mountains) could be cooler in the early-morning hours. So, be sure to check your local weather forecast (with NOAA Weather-Radio, local forecasts on radio, television or local newspapers, Internet, or your smart-telephone or smart-speaker) and bring a sweater and / or jacket with you if your location has a cooler weather forecast.

Be aware that sometimes August can be very humid with poor seeing conditions. And, the closer to the horizon, the worse the seeing conditions could be.

Binoculars and telescopes are not very useful for finding Meteors. Meteors streak across the sky in a very brief period of time, too short to aim binoculars or a telescope. So, the best way to view a Meteor Shower is to lie on the ground (perhaps on a blanket, sheet, or beach-towel—or possibly in a reclining beach or lawn-chair), in an area with a good view of the entire sky (with few obstructions such as buildings, trees, or hills, perhaps at a higher elevation), and keep scanning the entire sky with your unaided-eyes (one-power).

Meteor Showers appear to emanate from a Radiant point in the sky. For the Perseid Meteor Shower, the Radiant appears to be within the Constellation Perseus, named for the hero of Greek mythology (hence, the name Perseid Meteor Shower). However, you should not, necessarily, be looking only at Perseus, when looking for Meteors in this Shower.

Meteors can appear in any part of the sky at any time. In fact, looking towards Perseus may not result in finding the best Meteors. Meteors coming from the Apparent Radiant may be seen for a shorter time in the sky, with much shorter sky streaks.

A Meteor Shower normally consists of dust particles related to a Comet. Each time a Comet approaches the Sun, the Comet loses dust particles following the melting of ice on the Comet. These dust particles, called Meteoroids, continue to follow the same orbit as the Comet and form a Meteoroid stream. Each year, as the Earth orbits the Sun, the Earth passes through several of these Meteoroid streams, becoming Earth's Meteor Showers.

The Earth's gravity then attracts many of these Meteoroids to fall to Earth, and they are viewed by people as Meteors, as they burn-up, mostly but not always, high in the atmosphere. Most are extremely small and burn-up completely. From time-to-time, larger particles enter the Atmosphere and create brilliant displays known as Fire-balls or Bolides. If these particles are large enough, they may not completely burn-up and land on Earth as a Meteorite, perhaps even creating a crater on Earth if the Meteorite is large and heavy enough.

Many museums and science centers display Meteorites to the general public. From 1939 to 1991, the original Buhl Planetarium and Institute of Popular Science (a.k.a. Buhl Science Center – America's fifth major planetarium and Pittsburgh's science and technology museum from 1939 to 1991) displayed the fifth largest fragment of the Meteorite that formed Barringer Meteor Crater near Winslow, Arizona. Owned by the City of Pittsburgh, this large Meteorite is now displayed on the second floor of Pittsburgh's Kamin (Carnegie) Science Center, outside the entrance to the Henry Buhl, Jr. Planetarium. Meteorites are also on display in the Hillman Hall of Minerals and Gems at Pittsburgh's Carnegie Museum of Natural History.

Meteors can be seen any night of the year, although they are not predictable and are rare outside of one of the annual Meteor Showers. The vast majority of Meteors that can be seen during the Perseid Meteor Shower originate from Comet Swift-Tuttle, which has an orbital period of 133 years, leaving behind a trail of dust and grit. Comet Swift-Tuttle was discovered in 1862 and last returned for Earth viewing in 1992.

Comet Swift-Tuttle measures about 16 statute miles / 25 kilometers across, much larger than the object that is thought to have fallen to Earth which resulted in the extinction of the Dinosaurs (about 6 statute miles / 10 kilometers across) approximately 66 million years ago (after the Dinosaurs had lived on Earth for about 165 million years!).

Comet Swift-Tuttle will make a very close approach to the Earth in the year A.D. 4479. Scientists are now studying whether some day Comet Swift-Tuttle could impact the Earth. Comet Swift–Tuttle has been described as "the single most dangerous object known to humanity".

There are two additional Meteor Showers, which both peaked at the end of July, with some Meteors still visible in mid-August.

The Southern Delta Aquariid Meteor Shower peaked on Sunday, 2024 July 28 at 7:00 p.m. EDT / 23:00 UTC; these Meteors are visible each year between July 12 and August 23. It is not certain which Comet originated the Southern Delta Aquariids. This is considered a strong Meteor Shower, with 15-to-20 Meteors visible per-hour, around the peak of Shower; fewer would now be visible per-hour.

The evening of 2024 July 29 / early-morning of July 30 saw the peak of the Alpha Capracornid Meteor Shower. The official peak occurred on Monday, 2024 July 29 around 8:00 p.m. EDT / July 30, 0:00 UTC. At the peak time, 5 Meteors per-hour are expected, making the Alpha Capracornids a minor Meteor Shower; of course, now there would be fewer Alpha Capracornids visible per-hour. The Alpha Capracornids, which originated as remnants of Comet 169P / NEAT, are visible each year from July 3 to August 15.

Another minor Meteor Shower may be visible to some between August 28 and September 5 each year; the peak is expected August 31 / September 1. The astronomical peak for this Meteor Shower is on Saturday, 2024 August 31 at about 5:00 p.m. EDT / 21:00 UTC. The Aurigid Meteor Shower is believed to have originated as remnants of Comet Kless (C / 1911 N1). Astronomers do not know the composition of this Meteoric debris. So, it is uncertain how the Meteors from this Shower may interact with the Earth's atmosphere, and hence, scientists are unsure how visible this Shower may be each year.

So in mid-August, the time for viewing is right. And, of course, with the warm weather most of us experience in the Northern Hemisphere, this time of year, what could be better for viewing Meteors?

Of course, Meteor Showers, like all celestial observations, are weather-permitting. Even a few clouds could obscure quite a few Meteors.

If the weather in your area does not permit direct viewing of this Meteor Shower outdoors, it is possible (but not guaranteed) you may be able to use Google, Yahoo, Bing, Lycos, or your favorite Internet search engine to find special, Live-stream Web-casts of the Meteor Shower at one or more sites on the Internet.

A cautionary note for those who find it necessary to watch the Meteor Shower on the Internet. The video camera, used for each Live-stream Web-cast, can only aim at one part of the sky at a time. Hence, do not expect to see as many Meteors as you might see with your own eyes outside. Outdoors, you can easily scan the entire sky for Meteors, while a camera aimed at one area of the sky will only be able to see the Meteors that enter that particular field-of-view.

Internet Links to Additional Information ----

Perseid Meteor Shower: Link >>> https://en.wikipedia.org/wiki/Perseids

Comet Swift-Tuttle: Link >>> https://en.wikipedia.org/wiki/Comet_Swift%E2%80%93Tuttle

Constellation Perseus: Link >>> https://en.wikipedia.org/wiki/Perseus_%28constellation%29

South Delta Aquariid Meteor Shower:

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

Alpha Capracornid Meteor Shower: Link >>> https://en.wikipedia.org/wiki/Alpha_Capricornids

Aurigid Meteor Shower:

Link 1 >>> https://astronomyforbeginners.wordpress.com/2007/08/24/aurigid-meteor-shower-astronomy-for-beginners/

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

Meteor Shower: Link >>> https://en.wikipedia.org/wiki/Meteor_shower

Meteor: Link >>> https://en.wikipedia.org/wiki/Meteoroid#Meteor

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

Meteorite: Link >>> https://en.wikipedia.org/wiki/Meteoroid#Meteorites

Fifth largest fragment of the meteorite which struck Barringer Meteor Crater near Winslow, Arizona, which was displayed (1939 to 1991) at the original Buhl Planetarium and Institute of Popular Science (a.k.a. Buhl Science Center), America's fifth major planetarium & Pittsburgh's science and technology museum from 1939 to 1991. Today, this meteorite is displayed on the second floor of Pittsburgh's Kamin (Carnegie) Science Center, next to the Henry Buhl, Jr. Planetarium:
Link >>> http://buhlplanetarium2.tripod.com/Buhlexhibits.htm#meteorite

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

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

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

"Best Meteor Shower of Year Late-Night Sun. & Mon."

Friday, 2024 August 9.

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

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

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