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A total solar eclipse is one of the most spectacular natural
events to behold. Those who witness total solar eclipses
consider themselves fortunate. They carry an indelible
impression that is as much visual as it is emotional.
It is disheartening that most people never experience one of
the greatest astronomical and sensory events on our Planet.
Solar & Lunar Eclipses
It is an incredible coincidence that the Sun and
Moon appear the same size in the sky. It is even
more amazing that our Moon gets the chance to
perfectly eclipse the Sun. The odds of this coinci-
dence are brought to light when we consider that
our Moon is the only moon in our Solar System
that perfectly eclipses the Sun. All the other moons
of the Planets are either too large or too small
in their orbits to eclipse the Sun in precisely
the same manner as ours.
Although I have emphasized the glorious nature
of the total solar eclipse, I don’t want to undermine
the beauty of a total lunar eclipse. But they are two
different kinds of events. Total lunar eclipses are
great “casual” events that allow one to comfortably
sit and watch the coloration of the Moon gradually
change as it moves through the Earth’s shadow.
Overview of Solar and Lunar Eclipses
Both solar and lunar eclipses involve an alignment of the Earth,
Moon and Sun. A solar eclipse is the blocking of the Sun by the
Moon, either partially or totally. A lunar eclipse is the blocking of
the Moon’s light (from the Sun) by Earth’s shadow.
Solar eclipses can occur only at the time of New Moon; lunar
eclipses only at the time of Full Moon.
In order to see a total or annular solar eclipse, one must be
on a narrow path that can stretch for a thousand miles or so on
the Earth. Only those on the path will see the total or annular
eclipse — those near it will see only a partial eclipse. On the
other hand, lunar eclipses can be seen by almost everyone
on the night side of the world.
Facing page. The bright “flare” at the top of this total solar eclipse picture is known as a “diamond-ring effect” and is produced by a minute vestige of the Sun’s surface that pokes through the edge of the Moon. Above. Everyone gets to experience at least a few partial solar eclipses during their life.
Our
Moon is
the only
moon in
our Solar
System
that
perfectly
eclipses
the Sun.
Eclipses
Umbra and Penumbra Shadows
These are the names of the shadows
responsible for all eclipses. The umbra
is the innermost and darkest shadow.
The penumbra is a secondary shadow
around the umbra. You will see a solar
eclipse if you are in the Moon’s umbra
or penumbra shadow. Lunar eclipses
occur when the Moon passes into
Earth’s umbra or penumbra shadow.
Umbra and penumbra shadows are
visible whenever it is sunny. If you look at the edge of an
object’s shadow, you will notice that it is fuzzy. This fuzzy edge
is the penumbra and the main body of the shadow is the umbra.
Solar Eclipses
There are three types of solar eclipses: total, annular and partial.
They are illustrated and explained below.
Why do annular eclipses occur? The Moon’s orbit, like those
of all orbiting bodies, is an ellipse; so the distance from the Moon
to the Earth varies (see page 102). Annular eclipses occur when
the Moon is farther away in its orbit than usual, making the
apparent size of the Moon slightly smaller than the apparent
size of the Sun. In these instances, the Moon is simply too
small to totally block the Sun.
Solar & Lunar Eclipses
a
b
b
Sun
This exaggerated illustration depicts the formation of the umbra at (a) and the surrounding penumbra at (b). The geometry of these shadows is a result of the Sun’s diameter.
Total Solar Eclipse Moon completely blocks Sun. The irregularly shaped halo around the Moon is the Sun’s corona.
Annular Solar Eclipse Moon moves completely in front of the Sun but does not cover the Sun.
Partial Solar Eclipse Moon only partially blocks Sun. Those out- side the path of a total or annular eclipse only see a partial eclipse.
Eclipses
Moon at Full Moon
1 2
Umbra Shadow
Penumbra
Penumbra
Sunlight
TOTAL LUNAR ECLIPSES occur when the Moon enters the Earth’s umbra shadow. The Moon does not turn completely dark during a total lunar eclipse, instead, it turns a pretty red-orange color. A lunar eclipse is visible to almost half of the world. PARTIAL LUNAR ECLIPSES occur when only part of the Moon enters the Earth’s umbra shadow. Partial lunar eclipses will show one edge of the Moon turning a slight orange color. PENUMBRAL LUNAR ECLIPSES occur when the Moon only enters the Earth’s penumbra shadow. Penumbral lunar eclipses may not be noticeable.
Solar & Lunar Eclipses
Moon at New Moon
Sunlight
UMBRA. The darkest part of the shadow where a total eclipse can only be seen. On Earth, the umbra can reach 170 miles (270 km) wide and travel one-third of the way around the world in a few hours. PENUMBRA. The secondary shadow where only a partial eclipse of the Sun will be seen. The penumbra is thousands of miles wide and straddles the path of the umbra on the Earth’s surface. Observers outside of the penumbra will not see the Sun eclipsed.
The umbra path for the total solar eclipse of August 21, 2017. The penumbra stretches for thousands of miles on both sides of the umbra.
Lunar Eclipses^ Eclipses
Total Solar Eclipses
Observing Solar Eclipses
During a solar
eclipse, the Moon’s
progress can be
viewed with a
telescope that is
properly fitted with
a solar filter. Please
see page 222 on
safely observing
the Sun for more
information.
There are novel
ways to view the
progress of solar
eclipses. My favorite is
using trees. If you look at a tree’s shadow (the tree must have
leaves) during a solar eclipse, you will notice that mixed in with
the shadow are hundreds of crescent Suns. A tree with leaves
creates a multitude of pinholes (like a pinhole camera) that project
the outline of the Sun. Some trees work better than others.
Partial and Annular Eclipses. Partial eclipses can last for
several hours. They are not noticeable unless a substantial portion
of the Sun is covered by the Moon. Even with half of the Sun
eclipsed, you may not notice any appreciable difference in sunlight.
To observe an annular solar eclipse, consult the local media,
internet or popular monthly astronomy magazines for the location
of the eclipse path. You cannot see the annular eclipse if you are
not in its path. It will not get dark during an annular eclipse and the
Moon will only be completely in front of the Sun for several minutes.
A solar or eclipse viewer/filter is needed to view the Sun during
the entire partial and annular eclipse.
Total Solar Eclipse & Totality. Remember, to see a total
solar eclipse, you must be on the eclipse path. Consult the local
media, internet or popular monthly astronomy magazines for details
and locations of the path.
A total solar eclipse will last for several hours and is treated
as a partial eclipse until the time of totality, that is, when the
Moon completely blocks the Sun’s light. During the one to five
The multitude of crescents in this picture are the eclipsed Sun, projected through pinholes formed from the interweaving of leaves on a tree.
Observing Lunar Eclipses
minutes of totality, no solar filter is required. Everyone stands
and stares in wonder. Many things happen during totality. The
sky darkens a little (it does not get completely dark), and almost
immediately, the white shimmering corona is seen surrounding
the Moon. Around the Moon’s edge, the thin red ring of the
chromosphere may be visible along with prominences and flares
protruding outward. If you look at the sky around the Moon, you
will probably see a few stars and Planets (usually Venus and
Mercury) and if you scan the whole sky, you will see the umbra
shadow circling the sky and extending almost to the horizon.
The sky near the horizon is still light but may have a red coloring
like that at sunset. The entire scene is incredible. There is noth-
ing like it! No camera can capture the experience of totality, and
everyone is touched differently. People clap, cheer, cry and pray.
I recommend that everyone experience a total solar eclipse!
OBSERVING LUNAR ECLIPSES
No special equipment or caution is necessary to view lunar
eclipses but binoculars and telescopes can be used to enhance
the event. Lunar eclipses are especially enjoyable when you can
sit outside, talk with others and casually watch the event unfold.
For the most part, the Moon will turn a dark red-orange when
it is completely in Earth’s umbra shadow. Various hues of red and
orange will slowly dance across the Moon’s surface as it enters,
passes through and exits the umbra. Since the umbra is consid-
erably larger than the Moon, total lunar eclipses can last up to
32 hours. If the Moon crosses the umbra dead center, it takes
about an hour to completely enter the umbra. It will stay in the
umbra for 1 2 hours and finish as it started, taking an hour to
leave.
Eclipses
Eclipses
2000 – 2050 Solar and Lunar Eclipse Tables for
North America on Pages 230–
The solar and lunar eclipse tables on the following pages
summarize the location and time of these events. Since the
intensity of the event and the exact time vary considerably
depending on your viewing location, please consult your local
media, the internet or the popular monthly astronomy
magazines for details. Enjoy.
Solar Eclipses in North America
SOLAR Eclipses 2000 – 2031
July 30, 2000 Partial Around Sunset Alaska , Western Canada, Northwest December 25, 2000 Partial Around Noon Midwest , Continental US, Southern Canada December 14, 2001 Partial Early to Hawaii , Continental US Late Afternoon June 10, 2002 Partial Late Afternoon West , Midwest, Hawaii, Alaska, West Canada May 30, 2003 Partial Around Sunset Alaska April 8, 2005 Partial Late Afternoon Florida , South, Southwest July 21, 2009 Partial Around Sunset Hawaii May 20, 2012 Annular Around Sunset West , Hawaii, Alaska, Western Canada May 9, 2013 Partial Late Afternoon Hawaii October 23, 2014 Partial Mid Afternoon West , Midwest, Alaska, Western Canada March 8, 2016 Partial Around Sunset Hawaii , Alaska August 21, 2017 Total Around Noon Across the US! Hawaii, Canada & Alaska June 10, 2021 Partial Early Morning Northeast , East October 14, 2023 Annular Late Morning West, Continental US, Canada April 8, 2024 Total Around Noon Midwest , Continental US, Canada, Hawaii October 2, 2024 Partial Early Morning Hawaii August 12, 2026 Partial Early to Late Alaska to Northeast Morning January 26, 2028 Partial Late Morning Florida , South, East, Midwest January 14, 2029 Partial Around Noon Canada , Continental US June 11, 2029 Partial Around Sunset Alaska , Canada, Northwest November 14, 2031 Partial Mid Afternoon Hawaii , Southwest, South, Florida
Date of Solar Eclipse
Time of Day to View^1
Type of Locations^2 Solar Eclipse
(^1) Check media sources for specific times for your location. (^2) First listed area is most favorable viewing location.
Solar Eclipses in North America
SOLAR Eclipses 2033 – 2051
March 30, 2033 Total Morning Alaska , Canada, Hawaii, West, Midwest September 1, 2035 Partial Around Sunset Hawaii August 21, 2036 Partial Morning Alaska January 5, 2038 Partial Early Morning East , Florida July 2, 2038 Partial Early Morning Florida , Southeast, East June 21, 2039 Annular Early Morning Alaska , Canada, Hawaii, West, Midwest November 4, 2040 Partial Around Noon East , Continental US, Canada October 24, 2041 Partial Late Afternoon Hawaii April 19, 2042 Partial Around Sunset Alaska , Northwest Canada, Hawaii April 9, 2043 Partial Around Noon Alaska , Western Canada, Hawaii, Northwest August 22, 2044 Total Around Sunset Northwest , Alaska, Canada, Hawaii, West February 16, 2045 Partial Late Afternoon Hawaii August 12, 2045 Total Around Noon South to West , Hawaii, Canada, Alaska February 5, 2046 Annular Mid Afternoon Hawaii , Alaska, West June 11, 2048 Annular Early Morning Northern Midwest/ Canada , East, South, Florida May 31, 2049 Partial Morning Florida November 14, 2050 Partial Early Morning East Canada , Northeast April 10, 2051 Partial Around Sunset Alaska , Northwest Canada
Date of Solar Eclipse
Time of Day to View^1
Type of Locations^2 Solar Eclipse
(^1) Check media sources for specific times for your location. (^2) First listed area is most favorable viewing location.
Eclipse Tables
Eclipse Tables
Lunar Eclipses in North America
LUNAR Eclipses 2044 – 2051
September 7, 2044 Total Before Sunrise Hawaii, Alaska, West July 17, 2046 Partial Early Evening East Coast January 11, 2047 Total Early Evening Continental US, Canada, Alaska July 7, 2047 Total Before Sunrise Hawaii, Alaska, West December 31, 2047 Total Around Midnight Hawaii, Alaska, Continental US, Canada June 25, 2048 Partial Around Midnight Midwest, East December 19, 2048 Penumbra Around Midnight Hawaii, Alaska, Continental US, Canada October 29, 2050 Total Evening Continental US, Canada, Alaska April 25, 2051 Total Early Evening Continental US, Canada
Date of Lunar Eclipse
Time of Day to View^1
Type of Locations Lunar Eclipse
(^1) Check media sources for specific times for your location.
Facing page. Beautiful shades of orange and brown dance across the Moon during total lunar eclipses.
Eclipse Tables
