Friday, March 22, 2024

Can You See a Penumbral Lunar Eclipse ?

File:Geometry of a Lunar Eclipse.svg

This diagram shows that the Moon enters the very narrow, complete shadow of the Earth (Umbra) during a Total or Partial Eclipse of the Moon, while the Moon enters the much wider, but only partial shadow of the Earth (Penumbra) during a Penumbral Eclipse of the Moon. (Image Source: Wikipedia.org )

By Glenn A. Walsh

Reporting for SpaceWatchtower

Early Monday morning (2024 March 25), a Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon will be visible in the sky, weather-permitting. All Lunar Eclipses / Eclipses of the Moon are safe to look at with the naked-eyes (one-power), binoculars, or telescopes, without the need for special eye protection equipment. But, can you notice a Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon in the sky ?

Where Will This Eclipse Be Visible ?

The entire Eclipse, or portions of the Eclipse, will be visible throughout the world except Eastern Europe, most of Asia, eastern portion of Africa, and western portion of Australia.

What portions of this Eclipse are visible depends on when the Moon is above the Horizon in your particular location. Hence, to determine when the Moon is visible in the sky in your location, check the Moon-rise and Moon-set times for your locale. Near the end of this blog-post is an Internet link to the U.S. Naval Observatory web-site; plug-in your location to determine the local Moon-rise and Moon-set times.

As with any sky observations, this is of course weather-permitting.

When Will This Eclipse Be Visible ?

Monday Morning, 2024 March 25 ----

(EDT = Eastern Daylight Saving Time; UTC = Coordinated Universal Time)

Penumbral Lunar Eclipse Begins: 12:53:09 a.m. EDT / 4:53:09 UTC

Time of Full Moon Primary Phase: 3:00 a.m. EDT / 7:00 UTC

Time of Greatest Eclipse: 3:12:50.9 a.m. EDT / 7:12:50.9 UTC

Penumbral Lunar Eclipse Ends: 5:33:01 a.m. EDT / 9:33:01 UTC

Can This Eclipse Be Seen ?

During a Lunar Eclipse / Eclipse of the Moon, the Earth projects two types of shadows into Outer Space:

  • Umbral Shadow which is a deep, central region shadow that completely blocks direct sunlight.

  • Penumbral Shadow which is the outer portion of the shadow that only partially blocks direct sunlight.

During a Total Lunar Eclipse / Total Eclipse of the Moon the Moon is completely immersed by the Earth's Umbral Shadow, which blocks all direct sunlight. However, due to the Earth's atmosphere, some sunlight leaks through to the Moon, often causing a blood-red tint to the darkened Moon.

The Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon on March 25 will be a deep Penumbral Eclipse. At the time of Greatest Eclipse, the Moon will be completely within the Earth's Penumbral Shadow, but will not enter the Earth's Umbral Shadow. Hence, since the Moon will only be within the partial Penumbral Shadow, the Moon will not appear anywhere-near as dark as when the Moon enters the Umbral Shadow during a Partial Lunar Eclipse / Partial Eclipse of the Moon or a Total Lunar Eclipse / Total Eclipse of the Moon. In fact, during Greatest Eclipse the Moon will seem to dim just slightly.

Hence, it may be difficult to notice a Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon. The event will probably not be visible to most people until about 66 percent of the Moon's disk is immersed in the Earth's Penumbra Shadow.

The best way to observe a Penumbral Lunar Eclipse / Peunumbral Eclipse of the Moon would be to notice the brightness of the Moon shortly before the Eclipse begins, then notice the brightness again during the time of Greatest Eclipse. If you have a Light Meter, this could help determine the difference in brightness.

Eclipses usually come in pairs, and sometimes in threes. Hence, usually a Lunar Eclipse / Eclipse of the Moon precedes or follows a Solar Eclipse / Eclipse of the Sun by a couple weeks. The March 25 Eclipse, the first Eclipse of 2024, comes just two weeks (on Monday, 2024 April 8) before a grand Total Solar Eclipse / Total Eclipse of the Sun, which will cross much of the United States from Texas to Maine. Check the blog-post issued on 2024 March 18 regarding the April 8 Eclipse. An Internet link to the March 18 blog-post can be found near the end of this blog-post, in the section labeled “Related Blog-Posts”.

All Lunar Eclipses / Eclipses of the Moon occur at the time of the Primary Moon Phase of Full Moon. However, not all Full Moon Phases include a Lunar Eclipse / Eclipse of the Moon, since the Moon often travels above or below the Earth's shadow as projected into Outer Space.

The rising outdoor temperatures, as the days approach the Vernal Equinox, the official beginning of Spring on March 19 / 20 this year, leads to the thawing of the ground and the appearance of Earthworms, followed soon by Robins. Hence, the Full Moon of March is known as the Worm Moon.

However, Native Americans also had other names for the March Full Moon. With the increased cawing of crows, northern tribes knew the March Full Moon as the Crow Moon. They also called it the Snow Crust Moon, for the increased crusting of snow, caused by the thawing of snow by day and the freezing of the water by night.

The Abenaki tribe (New England and adjacent areas of Canada) called the March Full Moon “Mozokas” or the Moose Hunter Moon. The Creek nation, located further south, called it the “Tasahcusee” or Little Spring Moon. And, the Dakota Sioux actually called it the “Moon When Eyes Are Sore From Bright Snow.”

Colonial Americans called the March Full Moon the Sap Moon, for the time when maple trees were tapped. They also called it the Lenten Moon, as it was the last Full Moon of Winter usually occurring during the Christian period of Lent.

Full Moon names for March, in the Southern Hemisphere, include Harvest Moon and Corn Moon.

U.S. Naval Observatory Web-Site: Times of Sun / Moon Rise / Set:

Link >>> https://aa.usno.navy.mil/data/RS_OneDay

Internet Links to Additional Information ---

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

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

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

Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon:

Link >>> https://en.wikipedia.org/wiki/Lunar_eclipse#Penumbral_lunar_eclipse

Related Blog-Posts ---

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


"Spring Begins at Vernal Equinox Tue. Night." Mon., 2024 March 18.


"Slight Lunar Eclipse Friday Evening." Thur., 2013 Oct. 17.

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

               "Can You See a Penumbral Lunar Eclipse ?"

                  Friday, 2024 March 22.

            Artificial Intelligence not used in the writing of this article.

            © Copyright 2024 Glenn A. Walsh, All Rights Reserved

                             Like This Post? Please Share!

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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

Monday, March 18, 2024

U.S. Solar Eclipse April 8: Prepare for Safe Viewing

This great Solar Eclipse / Eclipse of the Sun will cross the United States Monday Afternoon, 2024 April 8. All areas of the United States will see the eclipse, although a Total Solar Eclipse / Total Eclipse of the Sun will only be seen in a narrow Path of Totality across the country from Texas to Maine. NO PARTIAL PHASE OF ANY SOLAR ECLIPSE / ECLIPSE OF THE SUN IS SAFE TO LOOK AT DIRECTLY, UNLESS YOU HAVE THE PROPER EQUIPMENT AND PROPER TRAINING TO DO SO SAFELY; OTHERWISE EYE-SIGHT COULD BE DAMAGED PERMANENTLY! This graphic shows one way to safely view the partial phases of a Solar Eclipse / Eclipse of the Sun by building a Solar Pinhole Viewing Box (a.k.a. Pinhole Camera) as shown above. After building this box, you must turn your back to the Sun and allow the light from the Sun to go through the pinhole and shine on a white piece of paper on the other end of the box (NEVER LOOK THROUGH THE PINHOLE AT THE SUN!).

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

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

(Graphic Source: Eric G. Canali, former Floor Operations Manager of the original Buhl Planetarium and Institute of Popular Science / Buhl Science Center (America's fifth major planetarium and Pittsburgh's science and technology museum from 1939 to 1991) and Founder of the South Hills Backyard Astronomers amateur astronomy club.

By Glenn A. Walsh

Reporting for SpaceWatchtower

One of the greatest coincidences in nature is a Total Solar Eclipse / Total Eclipse of the Sun, when the size of the Sun and the size of the Moon when viewed from Earth during an Eclipse coincide. Such an amazing Eclipse will cross much of the United States, as well as parts of Maritime Canada and central Mexico, on April 8, similar to how another such Eclipse crossed much of the United States in 2017. However, eye safety must be of paramount importance for anyone wanting to view this miraculous event.

The vast majority of the United States, along with much of Canada and Mexico, not within the Path of Totality of this Total Solar Eclipse / Total Eclipse of the Sun, will still experience a Partial Solar Eclipse / Partial Eclipse of the Sun. A Partial Solar Eclipse / Partial Eclipse of the Sun is when the Sun is eclipsed by the Moon, but the Moon does not block all portions of the surface of the Sun.

As with all celestial observations, views of any Eclipse are always weather-permitting.

For areas where inclement weather precludes direct viewing of the Total Solar Eclipse / Total Eclipse of the Sun, or for areas of the world where this Eclipse will not be visible in the sky, a Live-Stream Web-Cast of the event will be available on the Internet. The Internet link to this Live-Stream Web-Cast is available near the end of this blog-post.

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 will be less time) that the Eclipse can looked at 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.

Again, the short Totality Phase of a Total Solar Eclipse / Total Eclipse of the Sun, when the surface of the Sun is completely blocked by the Moon, is the only time the Eclipse can be viewed with the naked-eyes (one-power) without special equipment to protect the eyes. Never use binoculars or a telescope to view a Total Solar Eclipse / Total Eclipse of the Sun, because the magnification of these instruments can damage the eyes, at the moment the Moon slips out of the Totality Phase.

In fact, during the short Totality Phase of a Total Solar Eclipse / Total Eclipse of the Sun, only viewing with naked-eyes (one-power) will the Eclipse be visible. The Solar Corona is too dim to see while wearing Eclipse Glasses.

At all other times other than the Totality Phase, Solar Eclipse Glasses (also simply known as Eclipse Glasses) or other protection must be used to prevent permanent eye damage! This is true during all partial phases of any Total Solar Eclipse / Total Eclipse of the Sun, when any portion of the surface of the Sun is visible.

For areas which are not within the Path of Totality where a Partial Solar Eclipse / Partial Eclipse of the Sun will be visible, Solar Eclipse Glasses (also simply known as Eclipse Glasses) or other protection must be used at all times during the Eclipse to prevent permanent eye damage!

This is also true for any Solar Eclipse / Eclipse of the Sun which is not a Total Solar Eclipse / Total Eclipse of the Sun. This includes Partial, Annular, and Hybrid Solar Eclipses / Partial, Annular, and Hybrid Eclipses of the Sun. An Annular Solar Eclipse / Annular Eclipse of the Sun occurs when the Moon is farther from the Earth than normal in the elliptical lunar orbit; then, the Moon does not appear as large as the Sun and the small (but dangerous to eyes) portion of the surface of the Sun is visible around the shadow of the Moon. A Hybrid Solar Eclipse / Hybrid Eclipse of the Sun is a combination of Annular and Total Eclipses, when the Moon moves farther and / or closer to the Earth during the Eclipse event.

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.

This coincidence of nature will not always be the case. Since the creation of the Moon approximately 4.5 billion years ago, the Moon has been moving away from the Earth at a rate of about 1.496 inches / 3.8 centimeters per year. It is estimated that about 620 million years from now, a Total Solar Eclipse / Total Eclipse of the Sun will be an "on-again, off-again phenomenon", according mathematical astronomer Jean Meeus; he concludes the last Total Solar Eclipse / Total Eclipse of the Sun will occur 1.2 billion years from today.

Where Will This Eclipse Be Visible ?

The Total Solar Eclipse / Total Eclipse of the Sun will be visible early Monday Afternoon, 2024 April 8, along a narrow strip of land known as the Path of Totality from Texas to Maine. This includes the states of Oklahoma, Arkansas, Missouri, Illinois, Kentucky, Indiana, Ohio, Pennsylvania, New York, Vermont, New Hampshire, plus small parts of Tennessee and Michigan. This will include several cities and populated areas including San Antonio, Austin, Dallas / Fort Worth, Idabel OK, Little Rock AR, Poplar Bluff MO, Cape Girardeau MO, Paducah KY, Carbondale IL, Evansville IN, Bloomington IN, Indianapolis, Terre Haute IN, Dayton OH, Toledo OH, Akron OH, Cleveland, Erie PA, Buffalo, Rochester NY, Syracuse NY, Burlington VT, Montpelier VT, Lancaster NH, Caribou ME, and Presque Isle, ME.

All other parts of the contiguous 48 states of the United States will observe a Partial Solar Eclipse / Partial Eclipse of the Sun. Of course all observations in the sky are weather-permitting.

In Canada, this Eclipse will be visible in southern Ontario, Quebec, New Brunswick, Prince Edward Island, Nova Scotia (Cape Breton Island), and Newfoundland before passing into the Atlantic Ocean. This includes the cities and populated areas of Niagara Falls ON, Hamilton ON, Montreal, Fredericton NB, and Gander NL.

In Mexico, the Eclipse enters North America from the Pacific Ocean at Mazatlan. The Eclipse then travels north-east through Torreon, and enters Texas southwest of San Antonio.

When Will This Eclipse Be Visible ?

The times of this Eclipse, or any Solar Eclipse / Eclipse of the Sun, varies from one city to another. This is due to the fact that the Moon, and the Moon's shadow, is continually moving throughout any such Eclipse event, along with the continuing rotation of the Earth on our planet's axis.

In general, this Eclipse begins on Monday, 2024 April 8 in late morning in Mexico and shortly after local Noon in Texas and concludes in Maritime Canada in the late afternoon. The time of the Path of Totality (for this Eclipse, a fairly long 4 minutes and 28 seconds, approximately) would occur approximately half-way between the beginning and ending of the Eclipse in your area. These times are based on Local Daylight Saving Time, except in Mexico which recently converted to Local Standard Time year-round.

If you live in or near one of the states or cities which will observe this Eclipse, check with your local planetarium, science center or museum, or college or high school science department to find out the specific times in your area. Otherwise, check an Internet browser, which may be able to provide such specific times.

The last Total Solar Eclipse / Total Eclipse of the Sun visible in the United States was known as the Great American Solar Eclipse on Monday Afternoon, 2017 August 21. The next such Eclipse visible from the 48 contiguous states will occur on 2044 August 23.

Solar Eclipses always occur at the time of the Primary Phase of New Moon. Solar Eclipses do not occur during every New Moon Primary Phase, because most of the time the Moon's shadow misses the Earth. For this Solar Eclipse, the date and time of New Moon for April (Lunation #1253) is Monday Afternoon, 2024 April 8 at 2:21 p.m. Eastern Daylight Saving Time (EDT) / 18:21 Coordinated Universal Time (UTC).

Eclipses usually come in pairs, and sometimes in threes. Hence, usually a Lunar Eclipse / Eclipse of the Moon precedes or follows a Solar Eclipse / Eclipse of the Sun by a couple weeks. This month a deep Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon, the first Eclipse of 2024, will precede the April 8 Eclipse a week from today, early on Monday Morning, 2024 March 25.

How to Safely View This Eclipse & Any Solar Eclipse / Eclipse of the Sun ---

NEVER LOOK DIRECTLY OR INDIRECTLY AT ANY SOLAR ECLIPSE / ECLIPSE OF THE SUN, UNLESS YOU HAVE THE PROPER EQUIPMENT AND PROPER TRAINING TO DO SO SAFELY !!!

First, there is only one time when a Total Solar Eclipse / Total Eclipse of the Sun can be viewed safely, with the naked-eyes (one-power), without the use of additional safety equipment. This is during the very short time-span (for the April 8 Eclipse: maximum of approximately 4 minutes and 28 seconds - for some areas it will be less time) when the SURFACE OF THE SUN IS COMPLETELY OBSCURED BY THE MOON. ANY OTHER TIME, WHEN ANY PART OF THE SURFACE OF THE SUN IS VISIBLE, MUST BE VIEWED WITH THE PROPER SAFETY EQUIPMENT TO PREVENT DAMAGE TO THE EYES.

Safe Ways to View a Solar Eclipse / Eclipse of the Sun, When Any Portion of Solar Surface is Visible -

1) "Solar Eclipse Glasses” – Over the last 30 years, technology has provided a safe way to view a Solar Eclipse / Eclipse of the Sun. “Solar Eclipse Glasses,” or often just called “Eclipse Glasses,” have lenses made of aluminized and optical-grade Mylar (SPECIAL NOTE: Mylar used on Mylar balloons or food wrappers are NOT optical-grade), so dense that only light from the Sun can be seen with such Eclipse Glasses (more than 1,000 times darker than normal sunglasses!). Cheap, fake Eclipse Glasses have been advertised for sale, but should NEVER BE USED!

Solar Eclipse Glasses should ALWAYS be worn ANY TIME when directly viewing the Sun or when viewing any reflection of the Sun, even when there is no Solar Eclipse / Eclipse of the Sun (including when looking for large, naked-eye-visible Sunspots on the surface of the Sun).

    Legitimate Solar Eclipse Glasses should include the following number printed on the side of the glasses: ISO 12312-2. This number means that pair of Solar Eclipse Glasses meets the safety requirements of the ISO 12312-2 International Standard.

    To avoid the purchase of fake Eclipse Glasses, only buy or use Eclipse Glasses approved by the American Astronomical Society; go to this web-page on the American Astronomical Society web-site to read a list of the approved vendors of safe Eclipse Glasses:

    https://eclipse.aas.org/resources/solar-filters >

    Some local planetaria and science centers and museums are selling Eclipse Glasses in their gift shops. Also, a very limited number of Eclipse Glasses are being given-away at a limited number of local libraries (one pair of Eclipse Glasses per person).

    The following are instructions on how to properly handle and use Eclipse Glasses:

    a) Eclipse Glasses are fragile and should be treated gently at all times. It would be best to store the Eclipse Glasses in an envelope.

    b) BEFORE EVERY USE, point the Eclipse Glasses toward an artificial light source (i.e. lit light bulb). If any light can be seen coming through the Eclipse Glasses, or if any damage (scratches, tears or small holes or pin-holes) is seen on the lenses (check front and back of both lenses), or if the Mylar lenses are starting to separate from the cardboard frames of the Eclipse Glasses, that pair of Eclipse Glasses should be discarded (tear or cut Eclipse Glasses into small pieces, so no one accidentally uses them). USE OF DAMAGED ECLIPSE GLASSES WOULD ALLOW DANGEROUS SUNLIGHT TO ENTER THE EYES, WHICH COULD LEAD TO EYE-SIGHT DAMAGE.

    c) For people wearing eye-glasses, Eclipse Glasses should be placed over-top the eye-glasses--that is, sunlight should enter the Eclipse Glasses before entering the eye-glasses.

      d) PARTICULARLY IF YOU WEAR EYE-GLASSES: Solar Eclipse Glasses frames are made of cardboard and can easily fall off, particularly if the Solar Eclipse Glasses are placed over-top eye-glasses. Particularly if you place Solar Eclipse Glasses over-top eye-glasses, hold onto the Solar Eclipse Glasses WITH BOTH HANDS while in use, to be sure the Solar Eclipse Glasses do not inadvertently fall off and your eyes are exposed directly to sunlight.

      Always move your head away from the Sun before removing Solar Eclipse Glasses, anytime you wish to take off the Solar Eclipse Glasses.

    e) NEVER use Eclipse Glasses with any camera (including cell-phone or smart-phone cameras), telescope, binoculars, or any optical aid or device (except eye-glasses) that magnifies an image (or reflection of a magnified image); o be sGlasses are only designed to be used with the naked-eyes (one-power) or with eye-glasses.

    f) DO NOT attempt to clean or disinfect Eclipse Glasses lenses with water or any other cleaning agent. If Eclipse Glasses are carefully taken care-of, including storage in an envelope, cleaning lenses should not be necessary. If dust is a concern, do nothing more than gently blow-off dust.

    g) NEVER use any "home-made" or "hand-g wade" Solar Eclipse Glasses, or any Solar Eclipse Glasses produced by a vendor that is not approved by the American Astronomical Society. Such Eclipse Glasses have no quality control in production, hence there is no way to know if such Eclipse Glasses are safe for eye-sight.

    h) Eclipse Glasses are NOT toys. ECLIPSE GLASSES SHOULD ONLY BE USED BY CHILDREN, WITH ADULT SUPERVISION !

    i) Best if Solar Eclipse Glasses are used three minutes at a time. Always move your head and eyes away from the Sun before removing Solar Eclipse Glasses, to rest your eyes.

    j) When using Solar Eclipse Glasses, do not move; nothing except the Sun can be seen when the Solar Eclipse Glasses are being worn.

    k) Do not drive any type of vehicle or operate any type of machinery when Solar Eclipse Glasses are being worn.

    l) Do not use Solar Eclipse Glasses if you have a diseased eye, or after eye surgery.

    m) Solar Eclipse Glasses are designed for use over a period of three years. After three years, it would be best to acquire a new pair of Solar Eclipse Glasses.

  1. Solar Pinhole Viewing Box – The graphic at the beginning of this blog-post shows an indirect way to safely view the partial phases of a Solar Eclipse / Eclipse of the Sun (which includes Solar Eclipses / Eclipses of the Sun described as "Annular" or "Hybrid"), by building a Solar Pinhole Viewing Box (known as a Pinhole Camera). After building this box, you must turn your back to the Sun and allow the light from the Sun to shine through a pinhole (placed in a sheet of aluminum foil, adhered to the center of one end of the box) and shine on a white piece of typing, printer, or photocopy paper at the other end of the box; a small image of the Partial Solar Eclipse / Partial Eclipse of the Sun (which includes Solar Eclipses / Eclipses of the Sun described as "Annular" or "Hybrid") can then be seen projected on the white piece of paper. Do not expect a large or bright image of the Sun, since the pinhole cannot enlarge or brighten the image. NEVER LOOK THROUGH THE PINHOLE AT THE SUN! Of course, there are several variations on the idea of the Solar Pinhole Viewing Box including the simple use of two pieces of paper, one white with the other having the pinhole; in forests, natural pinhole cameras are sometimes formed through the dense foliage, with small images of the eclipsed Sun appearing on the ground.

    3) Public Observing Events – Often Science and educational institutions will sponsor public observing events where professional astronomical equipment, operated by trained astronomers, provide safe public viewing of a Solar Eclipse / Eclipse of the Sun or Solar Transit of a Planet. Such institutions may also include live Internet video-streaming of the event from NASA or other science organizations, particularly for a Solar Eclipse / Eclipse of the Sun where the institution's telescope observation cannot show a Total Eclipse, or when weather precludes local telescope observations of the event. Check with a local planetarium, astronomical observatory, science center or science museum, the science department (particularly if there is an astronomy or physics department) of a local college or university (or, possibly, high school), amateur astronomy club, or local library, to see if they are sponsoring such an event.

    4) SHADE RATING NUMBER 14 WELDER'S GLASS – SHADE RATING NUMBER 14 WELDER'S GLASS (AND ONLY WELDER'S GLASS RATED AT SHADE NUMBER 14, THE DARKEST SHADE AVAILABLE, IS STRONG ENOUGH TO BE SAFE FOR EYE-SIGHT) is safe enough for normal welding jobs and may be safe (but there are no guarantees) to view a Solar Eclipse / Eclipse of the Sun; welder's glass is designed specifically for welding jobs, not for solar observing. HOWEVER, only use Welder's Glass rated at Shade Number 14; as with sunglasses, it is NOT SAFE to stack several lighter shades of welder's glass together. Although Shade Rating Number 14 Welder's Glass may be safe, since the Sun is so bright, using a Shade Rating Number 14 Welder's Glass can be uncomfortable.

      5) Internet or Television – Of course, the safest way to view any special solar event is on an Internet Web-Cast or a Television Newscast or special program. Often during special solar events such a Solar Eclipse / Eclipse of the Sun or a Solar Transit of a Planet, professional organizations such as NASA, TimeandDate.com, Los Angeles' Griffith Observatory, and Slooh Community Observatory provide web-casts on the Internet of such special events; check the specific web-site for a schedule of such web-casts. For a very special event, sometimes television stations and / or networks, particularly Cable Television Channels specializing in news or Science, will also broadcast the event; check local listings for time and channel.

      Solar Eclipse / Eclipse of the Sun Research ---

      NASA, academic institutions, and Citizen Scientists will be conducting scientific research during the April 8 Eclipse. Such research is nothing new. It was during the 1919 Total Solar Eclipse / Total Eclipse of the Sun that astronomers confirmed Albert Einstein's General Theory of Relativity.

      On April 8, NASA will launch three sounding rockets from Wallops Island, Virginia, to study how the sudden drop in sunlight during the Eclipse affects Earth's Upper Atmosphere. The first rocket will be launched 35 minutes before local peak Eclipse. The second rocket will be launched during local peak Eclipse, when the Earth's Ionosphere experiences maximum shielding from solar radiation. The third rocket will be launched 35 minutes after the local peak Eclipse as solar radiation once again reaches the Ionosphere.

      Other NASA research will include chasing the Eclipse with NASA's High-Altitude Research Airplanes, Airborne Imaging and Spectroscopic Observations of the Solar Corona, and the Super Dual Auroral Radar Network (SuperDARN) where radar signals bounced off the Ionosphere will be analyzed.

      Fifty-three teams made up of 750 student participants from 75 participating academic institutions will be involved in the Nationwide Eclipse Ballooning Project. Engineering teams and Atmospheric Science teams will also be studying the Earth's Ionosphere. This will include live-stream video, weather sensors, and individually-designed experiments. One team will use the 34-meter Goldstone Apple Valley Radio Telescope (GAVRT) to observe solar “active regions”, which often have sunspots.

      NASA also has several research projects for which the general public can participate as Citizen Scientists. This includes Citizen Science experiments to study the Sun, Earth and Earth's Environment, and studies of animal and insect behavior during the Eclipse. Near the end of this blog-post is an Internet link to a listing of these projects.

Live-Stream Web-Cast of Eclipse, for areas with inclement weather or parts of the world where Eclipse is not visible in the sky:

Link >>> https://www.timeanddate.com/live/eclipse-solar-2024-april-8

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

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

NASA Citizen Science Projects During the Eclipse Regarding Studies of the Sun and Earth & Earth's Environment:

Link >>> https://science.nasa.gov/eclipses/future-eclipses/eclipse-2024/eclipse-2024-citizen-science/

NASA Citizen Science Projects During the Eclipse Regarding Studies of Animal & Insect Behavior:

Link >>> https://science.https://science.nasa.gov/solar-system/skywatching/sense-the-solar-eclipse-with-nasas-eclipse-soundscapes-project/nasa.gov/solar-system/skywatching/sense-the-solar-eclipse-with-nasas-eclipse-soundscapes-project/

Internet Links to Additional Information ---

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

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

Solar Corona: Link >>> https://en.wikipedia.org/wiki/Stellar_corona

NASA Studies Solar & Earth Atmospheres during Eclipse:

Link >>> https://science.nasa.gov/eclipses/future-eclipses/eclipse-2024/eclipse-2024-science/

Related Blog-Posts ---

"100 Years Ago: U.S. Scientist Questions Evidence Proving General Theory of Relativity." Wed., 2019 Nov. 13.


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

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

               "U.S. Solar Eclipse April 8: Prepare for Safe Viewing"

                  Monday, 2024 March 18.

            Artificial Intelligence not used in the writing of this article.

            © Copyright 2024 Glenn A. Walsh, All Rights Reserved

                             Like This Post? Please Share!

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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

Spring Begins at Vernal Equinox Tue. Night

    http://buhlplanetarium.tripod.com/pix/graphics/solsticeimage008.png

This diagram shows the position of the Earth, in relation to the Sun, at the time of the Vernal Equinox at the official beginning of the season of Spring in the Earth's Northern Hemisphere (Autumn in Earth's Southern Hemisphere), 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 fifth major planetarium and Pittsburgh's science and technology museum from 1939 to 1991, and Founder of the South Hills Backyard Astronomers amateur astronomy club; permission granted for only non-profit use with credit to author.) 

By Glenn A. Walsh

Reporting for SpaceWatchtower

Spring begins Tuesday Evening at the moment of the Vernal Equinox in Earth's Northern Hemisphere. In the Southern Hemisphere of Earth, this marks the astronomical beginning of the season of Autumn.

The Vernal Equinox occurs on Earth at precisely: Tuesday Evening, 2024 March 19 at 11:06 p.m. Eastern Daylight Saving Time (EDT) / March 20 at 3:06 Coordinated Universal Time (UTC). While Spring usually begins on March 20 or March 21, the March 19 start date for Spring this year is due to 2024 being a Leap-Year; the extra day in February means that the Vernal Equinox begins on an earlier date.

As the diagram at the beginning of this blog-post demonstrates, on the day of 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 a 23.439281-degree angle from the plane of the Earth's orbit around the Sun, which is part of the Ecliptic of our Solar System. 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 a half-year later during that hemisphere's season of Winter. As mentioned, during an Equinox (about half-way between Summer and Winter, and about half-way between Winter and Summer) both planetary hemispheres receive an equal amount of solar radiation.

"Vernal" is a Latin term for Spring. 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.

As the Equinox occurs a day earlier due to Leap-Year, so does this year's Equilux. This year, Equilux occurred on March 16. Most years, in addition to being St. Patrick's Day, the Equilux usually occurs on March 17. Equilux ("equal-light") is 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 and 3-to-4 days after the Autumnal Equinox (Equilux is on September 25, while the Autumnal Equinox is ~ September 22 or 23).

An urban legend that has been making the rounds for decades, now exacerbated by the Internet and Social Media, 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 even and stiff bristles) on an Equinox, it can do so any day of the year!

In ancient times, the Vernal Equinox was considered the beginning of the new calendar year, as Spring brought new life after the cold Winter months. The calendar year was then defined as the time from one Vernal Equinox to the next. This is known as the Tropical Year: 365 days, 5 hours, 48 minutes, and 45 seconds.

This was when most of Western Civilization used the Julian Calendar, recommended by astronomer Sosigenes and approved by Roman leader Julius Caesar in 46 B.C. Due to the difference between the Julian Calendar and the calendar we use today, known as the Gregorian Calendar, the Vernal Equinox then occurred on March 25, later observed by Christians as the Feast of the Annunciation (observed nine full months before Christmas Day). As part of the Gregorian Calendar reform, in October of 1582, Roman Catholic Pope Gregory XIII chose the Feast of the Circumcision of Christ (January 1) as the beginning of the New Year in the Roman Catholic Church's Liturgical Year.

As a legacy to the Vernal Equinox originally considered the beginning of the New Year, astronomers have set the Vernal Equinox as the beginning point of the coordinate system in the sky. Astronomers measure the sky using Right Ascension (measured in hours, minutes, and seconds), which is analogous to Longitude on Earth, and Declination (measured in degrees, minutes, and seconds), which is analogous to Latitude on Earth. Precisely on the Vernal Equinox each year, the sky coordinates are reset to Right Ascension 0 hour, 0 minute, 0 second, and Declination 0 degree, 0 minute, 0 second.

The Vernal Equinox continues to be considered the beginning of the New Year, or an important holy day, in several other places on Earth ---

* Beginning of New Year (using the Solar Calendar) - Nowruz: Afghanistan and Iran / Persia.

* Holy Day for adherents of the Zoroastrian Religion (the three Magi, who the Christian Bible reports visited the Christ Child after following the Star of Bethlehem / Christmas Star, were adherents of the Zoroastrian Religion).

* Holy Day for adherents of the Bahá'í Faith: Baha'i Naw-Ruz, one of nine holy days of the Bahá'í Faith.

NASA and the European Space Agency (ESA) observe Sun - Earth Day on or near the Vernal Equinox. This is a joint educational program started in 2000, to popularize the knowledge about the Sun, and the way it influences life on Earth, among students and the public. This is part of Solar Week, which is the calendar week that includes the Vernal Equinox.

March 20, usually the date of the Vernal Equinox, is also considered Women in Science Day or Hypatia Day. Hypatia was an astronomer, mathematician, philosopher, and teacher in 5th century Alexandria, Egypt, then part of the Eastern Roman Empire. She was a prominent thinker in Alexandria whose murder (in March of A.D. 415) shocked the Empire; she became a secular “martyr for philosophy”. The Vernal Equinox is considered a logical day to celebrate the life of Hypatia, as her last days were dedicated to finding the precise time of the Vernal Equinox, as a means to set the date of Easter.

The first week of Spring, beginning with the Vernal Equinox, has been declared by physicians as Medicine Cabinet Clean-Up Week. To avoid prescription drug abuse, particularly important at this time of the opioid crisis, physicians encourage everyone to get rid of unused and no-longer-needed medications and other drugs, which may have lingered in the household, as part of an annual Spring cleaning. Several states have prescription drug take-back locations, where these drugs can be dropped-off; some are located in pharmacies and / or municipal building lobbies.

The week of the Vernal Equinox is also the beginning of the National Cherry Blossom Festival held each year in Washington, DC, which begins on March 20. This festival commemorates the 1912 gift of 3,000 cherry trees from the Mayor of Tokyo to the City of Washington. The festival runs through April 14 this year. For 2024, the National Park Service predicts the Peak Bloom of the Cherry Blossoms will be March 23 to March 26.

This year, the Full Moon Primary Phase, on Monday, 2024 March 25 at 3:00 a.m. EDT / 7:00 UTC, also brings a deep Penumbral Lunar Eclipse / Penumbral Eclipse of the Moon, with the greatest eclipse on Monday, 2024 March 25 at 3:12:50.9 a.m. EDT / 7:12:50.9 UTC. Penumbral Eclipses are difficult to observe. You would need to notice the brightness of the Moon before the Eclipse begins, and then see if you can discern a noticeable decrease in brightness during the time of greatest eclipse.

Internet Links to Additional Information ---

Vernal Equinox -

Link 1 >>> https://scienceworld.wolfram.com/astronomy/VernalEquinox.html

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

Season of Spring: Link >>> http://en.wikipedia.org/wiki/Spring_%28season%29

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

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

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

Sun - Earth Day: Link >>> https://en.wikipedia.org/wiki/Sun-Earth_Day 

Women in Science Day / Hypatia Day: Link >>> https://www.change.org/p/canada-s-parliament-commemorating-the-first-female-astronomer-hypatia-of-alexandria

Medicine Cabinet Clean-Up Week: Link >>> https://www.prnewswire.com/news-releases/include-medicine-cabinets-on-your-spring-cleaning-list-300042760.html 

National Cherry Blossom Festival: Link >>> https://nationalcherryblossomfestival.org/

Related Blog-Post ---

"Solar Calendar Leap-Year Day Eclipse in 1504 Saves Columbus' Crew." Thur., 2024 Feb. 29.

Link >>> https://spacewatchtower.blogspot.com/2024/02/solar-calendar-leap-year-day-eclipse.html

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

               "Spring Begins at Vernal Equinox Tue. Night"

                  Monday, 2024 March 18.

            Artificial Intelligence not used in the writing 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