Google Answers Logo
View Question
Q: Solar Total Eclipse effects on Moon ( No Answer,   3 Comments )
Subject: Solar Total Eclipse effects on Moon
Category: Science > Astronomy
Asked by: fcojfdez-ga
List Price: $10.00
Posted: 29 Mar 2006 03:44 PST
Expires: 28 Apr 2006 04:44 PDT
Question ID: 713103
Has a Solar Total Eclipse any specific effect on Moon's attributes or
behaviour, such as changes in temperature, speed, gravity, etc.,
during the phenomenon unfolding? Can you explain them? How can we
measure these effects?
There is no answer at this time.

Subject: Re: Solar Total Eclipse effects on Moon
From: demianunique-ga on 29 Mar 2006 05:12 PST
( I think There is no effects of total Solar Eclipse on moon such as
speed or gravity.Otherwise the beahaviour of moon can be effected and
this will also effect the Earth behave differently so that means of
changin climates  and maybe the earths orbit.In 1935 there were 5
Eclipses sometimes the eclipses maybe total I have the details below 
but I dont have any idea about the temperature(The moon dont have any
atmosphere)I have made a detailed search and there are no information
or question or comment about the subject.Today there is another solar
total ecylipse,and I will be able to  have more info tomorrow about
the subject as I will ask My University (we have an Astronomy
Laboratory  at the university) about the subject so that we can both
learn about it.Very interesting Question :)
Near the beginning and end of total solar eclipse, the thin slice of
the Sun visible appears broken up into beads of light. These lights
are called 'Baily's Beads' after the British astronomer Francis Baily
who discovered them. They occur because the edge of the Moon is not
smooth but jagged with mountain peaks.
When just one bead is visible, the effect is often likened to a diamond ring.
A solar eclipse occurs when the Moon passes in front of the Sun and
obscures it totally or partially. This configuration can only exist at
New Moon, when Sun, Moon and Earth are on a single line with the Moon
in the middle.

There are four types of solar eclipses:

    * A partial solar eclipse occurs when the Sun is only partially
overlapped by the Moon.

    * A total solar eclipse occurs when the Moon completely obscures
the Sun. This happens when the Moon is near perigee and its angular
diameter as seen from Earth is identical to or slightly larger than
that of the Sun. A total solar eclipse is the only opportunity to
observe the Sun's corona without specialised equipment.

    * An annular (ring-formed) eclipse occurs when the Moon's center
passes in front of Sun's center while the Moon is near apogee. The
Moon's angular diameter is then smaller than that of the Sun so that a
ring of the Sun can still be seen around the Moon. This is similar to
a penumbral eclipse.

    * A hybrid eclipse occurs when the curvature of Earth's surface
causes a single solar eclipse to be observed as annular from some
locations but total from other locations. A total eclipse is seen from
places on the Earth's surface that lie along the path of the eclipse
and are physically closer to the Moon, and so intersect the Moon's
umbra; other locations, further from the Moon, fall in the Moon's
antumbra and the eclipse is annular.

The term "solar eclipse" is a misnomer: the phenomenon is actually an
occultation. An "eclipse" occurs when one celestial object passes into
the shadow cast by another (as with an eclipse of the Moon). An
"occultation' occurs when one body passes in front of another. When at
its new phase the Moon passes in front of, or occults, the Sun, as
seen from Earth, the Moon also casts a small shadow on Earth. An
"occultation" of the Sun is therefore also a partial "eclipse" of

Observing a solar eclipse

Looking at the Sun is dangerous at any time when any part of the
brilliant visible disk of the Sun (its photosphere) is visible; to do
so can cause permanent eye damage. This is true at any time, including
during solar eclipses; since an eclipse offers an unusually high
temptation to look at the Sun, there is a high incidence of eye damage
caused during solar eclipses. Viewing the Sun through any kind of
optical aid - binoculars, a telescope, or even a camera's viewfinder-
is extremely dangerous.

Safe Solar Viewing

The Sun can be viewed using appropriate filtration to block the
harmful part of the Sun's radiation. Note that sunglasses are of
little use, since they don't block the harmful and invisible infra-red
radiation which causes retinal damage; other improvised methods, such
as using a reflection in water, or looking through a compact disk, are
equally dangerous. Only properly designed and certified solar filters
should ever be used for direct viewing of the Sun; and these must be
in perfect condition, as even a small defect could cause damage.

The safest way to view the Sun is by indirect projection. This can be
done by projecting an image of the sun onto a white piece of paper or
card using a pair of binoculars (with one of the lenses covered), a
telescope, or another piece of cardboard with a small hole in it
(about 1 mm diameter), often called a pinhole camera.

The projected image of the sun can then be safely viewed; this
technique can be used to observe sunspots, as well as eclipses.
However, care must be taken to ensure that no-one looks through the
projector (telescope, pinhole, etc.) directly, as this will cause
severe eye damage; particular care should be taken if children are
present.It is safe to directly observe the total phase of a total
solar eclipse, when the Sun's photosphere is completely covered by the
Moon; indeed, this is a very beautiful sight.

The Sun's faint corona will be visible, and even the chromosphere,
solar prominences, and possibly even a solar flare may be visible. The
danger here is of being caught out by the end of the total phase, and
the return of the "exposed" Sun; because all parts of the Sun's disk
are of similar intensity, even a tiny sliver of the Sun could cause
permanent eye damage. For this reason, viewing the total phase of a
solar eclipse through binoculars or a telescope should not be

Eclipse frequency and cause 
Diagram of solar eclipse

Total and annular eclipses both occur when the Moon lines up with the
Sun exactly, but since the Moon's orbit is not perfectly circular it
is sometimes farther away from Earth and doesn't always cover the
entire solar disc from an Earthly vantage point.

It is one of the most remarkable coincidences of nature that the Sun
lies approximately 400 times as far away from Earth as does the Moon,
and the Sun is also approximately 400 times as large in diameter as
the Moon. As a result, as seen from Earth, the Sun and the Moon appear
to be nearly the same apparent size. The Moon orbits Earth in an
elliptical, or elongated orbit, however, and not in a circular orbit.

Thus during about 55-60% of its orbit the Moon is far enough from
Earth ("apogee") that it is too small to cover the Sun's surface
completely. During the remaining portion of its orbit, it is closer to
Earth ("perigee") and large enough in apparent size to cover the Sun

When a solar eclipse occurs near apogee, there is therefore a small
ring or annulus of Sun that remains uncovered even at the moment of
maximum eclipse. This produces an "annular" eclipse, during which the
brilliant and blinding uncovered ring of the Sun makes the solar
corona invisible. When a solar eclipse occurs near perigee, however,
the Moon is close enough to Earth and large enough in the sky that it
can cover the entire bright surface (the photosphere) of the Sun
completely, and the observer sees a total eclipse, at which time the
ghostly white solar corona appears.

A solar eclipse can only be seen in a band across Earth as the Moon's
shadow moves across its surface, while a total or annular eclipse is
actually total or ring-formed in only a small band within this band
(the eclipse path), and partial elsewhere (total eclipse takes place
where the umbra of the Moon's shadow falls, whereas a partial eclipse
is visible where the penumbra falls). The full band is generally
around 100 km in width. The eclipse path will be widest if the Moon
happens to be at perigee, in which case the eclipse path alone can
reach 270 km in width.

Total solar eclipses are rare events. Although they occur somewhere on
Earth approximately every 18 months, it has been estimated that they
recur at any given spot only every 300 to 400 years. And after waiting
so long, the total solar eclipse only lasts for a few minutes, as the
Moon's umbra moves eastward at over 1700 km/h.

Totality can never last more than 7 min 40 s, and is usually a good
deal shorter. During each millennium there are typically fewer than 10
total solar eclipses exceeding 7 minutes. The last time this happened
was June 30, 1973. Those alive today probably won't live to see it
happen again - on June 25, 2150. The longest total solar eclipse
during the 8,000-year period from 3000 BC to 5000 AD will occur on
July 16, 2186, when totality will last 7 min 29 s. (eclipse
predictions by Fred Espenak, NASA/GSFC.)

For astronomers, a total solar eclipse forms a rare opportunity to
observe the corona (the outer layer of the Sun's atmosphere). Normally
this is not visible because the photosphere is much brighter than the

Calculating the date of a solar eclipse

If you know the date and time of a solar eclipse, you can predict
other eclipses using eclipse cycles. Two well-known eclipse cycles are
the Saros cycle and the Inex cycle. The Saros cycle is probably the
most well known, and one of the best, eclipse cycles. The Inex cycle
is itself a poor cycle, but it is very convenient in the
classification of eclipse cycles. After a Saros cycle finishes, a new
Saros cycle begins 1 Inex later (hence its name: in-ex).
The longest duration for a total solar eclipse is 7.5 minutes.

A total solar eclipse is not noticable until the Sun is more than 90
percent covered by the Moon. At 99 percent coverage, daytime lighting
resembles local twilight.

Eclipse shadows travel at 1,100 miles per hour at the equator and up
to 5,000 miles per hour near the poles.

The width of the Moon's shadow is at most 170 miles wide.

The maximum number of solar eclipses (partial, annular, or total) is 5 per year.

There are at least 2 solar eclipses per year somewhere on the Earth.

A total eclipse can only happen during a new moon.

Total solar eclipses happen about once every year or two.

Nearly identical eclipses (total, annual, or partial) occur after 18
years and 11 days, or every 6,585.32 days (Saros Cycle).

From the Earth's surface, the Sun's corona ("crown") can ONLY be seen
during a total eclipse.
Subject: Re: Solar Total Eclipse effects on Moon
From: myoarin-ga on 29 Mar 2006 09:18 PST
Hi Fcojfdez-ga,

From the moon's point of view, the only thing that is different during
an earthly solar eclipse is that sunlight reflected from earth will be
greater than at any other time, but this will be an extremely minor
difference from the light reflected when the moon passes slightly of
the direct line between sun and earth.

Oh, a second thing:  the moon will be at the point with greatest
simultaneous effect of gravity from the sun and earth, but again only
a probably unmeasurable difference to other times, especially when one
remembers that the moon's distance from earth varies during its
elliptical path, so that at the moment of an eclipse it may be further
from earth than at other times.

"A total eclipse can only happen during a new moon."

ANY solar eclipse can only happen during a new moon (just as any
eclipse of the moon can only occur during a full moon).
Subject: Re: Solar Total Eclipse effects on Moon
From: fcojfdez-ga on 19 Apr 2006 04:54 PDT
Thanks demianunique-ga for your explanation. It was clarifying. I hope
you could reach any answer from your Astronomy Laboratory. Didn't you?

And thanks myoarin-ga for your comments. You are very aligned with my
inquiry. It is supposed that some circumstances are interrupted or
magnified during the 4-7 minutes that a total solar eclipse lasts.
e.g. Light reflected from Earth to Moon surface, distance between Moon
and Sun and between Moon and Earth....

I am wondering if the magnitude of these changes, plus the short
duration of the phenomenom, are sufficient for affecting Moon's
attributes..., and if these changes are measurable....

Important Disclaimer: Answers and comments provided on Google Answers are general information, and are not intended to substitute for informed professional medical, psychiatric, psychological, tax, legal, investment, accounting, or other professional advice. Google does not endorse, and expressly disclaims liability for any product, manufacturer, distributor, service or service provider mentioned or any opinion expressed in answers or comments. Please read carefully the Google Answers Terms of Service.

If you feel that you have found inappropriate content, please let us know by emailing us at with the question ID listed above. Thank you.
Search Google Answers for
Google Answers  

Google Home - Answers FAQ - Terms of Service - Privacy Policy