The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists
of hot plasma interwoven with magnetic fields. The energy of sunlight supports almost all
life on Earth by photosynthesis and drives Earth's climate and weather. The enormous effect of the Sun on the Earth
has been recognized since prehistoric times, and the Sun has been regarded by
some cultures as a Deity. An accurate
scientific understanding of the Sun developed slowly, and as recently as the
19th century prominent scientists had little knowledge of the Sun's physical
composition and source of energy. This
understanding is still developing; there are a number of present-day anomalies
in the Sun's behavior that remain unexplained.
As
seen from the Earth, a solar eclipse
is a type of eclipse that occurs when the Moon passes between the Sun and
Earth, and the Moon fully or partially blocks (occults) the Sun. This can happen only at new moon, when the
Sun and the Moon are in conjunction as seen from Earth in an alignment referred
to as syzygy. In a total eclipse, the
disk of the Sun is fully obscured by the Moon. In partial and annular eclipses only part of
the Sun is obscured.
Since looking directly at
the Sun can lead to permanent eye damage or blindness, special eye protection
or indirect viewing techniques are used when viewing a solar eclipse. It is technically safe to view only the total
phase of a total solar eclipse with the unaided eye and without protection,
however this is a dangerous practice as most people are not trained to
recognize the phases of an eclipse which can span over two hours while the
total phase can only last up to 7.5 minutes for any one location.
It's
easy to imagine how our earliest ancestors must have reacted to the sudden
disappearance of the sun, and over time the phenomenon has been seen as both
fascinating and terrifying, a signal of the displeasure of the Gods, or an omen
of bad things to come.
Historical
eclipses are a very valuable resource for historians, in that they allow a few
historical events to be dated precisely, from which other dates and ancient
calendars may be deduced. A solar
eclipse of June 15, 763 BC mentioned in an Assyrian text is important for the
Chronology of the Ancient Orient. The
Emperor Zhong Kang supposedly beheaded two astronomers, Hsi and Ho, who failed
to predict an eclipse 4,000 years ago. Perhaps
the earliest still-unproven claim is that of archaeologist Masse, who
putatively links an eclipse that occurred on May 10, 2807 BC with a possible
meteor impact in the Indian Ocean on the basis of several ancient flood myths
that mention a total solar eclipse.
Eclipses
have been interpreted as omens or portents. The ancient Greek historian Herodotus wrote
that Thales of Miletus predicted an eclipse that occurred during a war between
the Medians and the Lydians. Both sides
put down their weapons and declared peace as a result of the eclipse.
Many
cultures explain eclipses, both solar and lunar, as a time when demons or
animals consume the sun or the moon. The
Vikings saw a pair of sky wolves chasing the sun or the moon. When one of the wolves caught either of the
shining orbs, an eclipse would result. In
Vietnam, a frog or a toad eats the moon or the sun. While people of the Kwakiutl tribe on the
western coast of Canada believe that the mouth of heaven consumes the sun or
the moon during an eclipse.
In
order to combat this devouring, people in many cultures made noise in order to
scare the demon or animal away. People
banged pots and pans or played on drums to get whatever was swallowing the sun
or the moon to go away.
Other
myths tell of deception and theft to explain the sun's disappearance during an
eclipse. Korean eclipse mythology
involves fire dogs that try to steal the sun or the moon. On orders from a King, the mythical canines
try their best to capture the fiery sun or the ice-cold moon. They always fail, but whenever they bite
either orb, an eclipse results.
On October
23, 2014 a Partial Solar Eclipse will occur. Continents seeing at least a partial eclipse
include East Asia, much of North America, Pacific and Atlantic. The center of
the Moon's shadow will miss the earth, passing above the north pole, but a
partial eclipse will be visible at sunrise in far eastern Russia, and before
sunset across most of North America.
Event
|
UTC Time
|
First
location to see partial eclipse begin
|
Oct
23 at 7:38 PM
|
Maximum
Eclipse
|
Oct
23 at 9:45 PM
|
Last
location to see partial Eclipse end
|
Oct
23 at 11:52 PM
|
It's
an amazing experience, even though we now know it's just the moon moving in
front of the sun. They're a chance to
see the universe working.
Skoll the wolf
who shall scare the Moon
Till he flies to the Wood-of-Woe:
Hati the wolf, Hridvitnir's kin,
Who shall pursue the Sun.
~ Grimnismal, The Elder Edda
Till he flies to the Wood-of-Woe:
Hati the wolf, Hridvitnir's kin,
Who shall pursue the Sun.
~ Grimnismal, The Elder Edda
No comments:
Post a Comment