F6 ECLIPSES

ECLIPSES

* An eclipse is the darkening of a heavenly body when the shadow of one object in space falls on another object.
* Eclipses occur when the Sun or the Moon is hidden from our view for a short period.
* Greek word – eclipse = failing to appear
Possible only when Sun, Moon and Earth are in a straight line
Planet farther away from Sun is then in shadow of the nearer body
The darker side of the shadow is called umbra and the partial shadow surrounding the image is called penumbra.

SOLAR ECLIPSE

During a solar eclipse, the moon passes directly between the Earth and the sun, blocking out the sun as seen from Earth. A path of totality is formed where the moon blocks out the entire sun and observers can see a total eclipse. Outside the path of totality, only a partial eclipse can be viewed.

Every total eclipse begins with a series of partial phases which may last an hour or more. However, the total phase or “totality” never lasts more than 7.5 minutes.
This time series photo shows an entire total solar eclipse, from start to finish over a period of over two hours.

In the last seconds before totality begins, the remaining bit of Sun resembles a dazzling jewel as the ring-like corona appears.

The Sun, the Moon, and two photographers all lined up last month in Antarctica during an unusual total eclipse of the Sun. Even given the extreme location, a group of enthusiastic eclipse chasers ventured near the bottom of the world to experience the surreal momentary disappearance of the Sun behind the Moon. One of the treasures collected was the above picture -- a composite of four separate images digitally combined to realistically simulate how the adaptive human eye saw the eclipse. As the image was taken, both the Moon and the Sun peaked together over an Antarctic ridge. In the sudden darkness, the magnificent corona of the Sun became visible around the Moon. Quite by accident, another photographer was caught in one of the images checking his video camera. Visible to his left are an equipment bag and a collapsible chair.
(APOD: 2003 December 8 - An Antarctic Total Solar Eclipse )

Partial Eclipse of Oct. 14, 2004 (Hawaii)
Partial eclipses are visible over a much larger part of Earth than total eclipses. So they are seen by many more people.

LUNAR ECLIPSE :
A lunar eclipse occurs when the Earth is between Sun and the moon – sun, earth and moon arein a straight line with the earth in-between the sun and moon.
Shadow of the earth falls on the moon .
Usually happens on Full Moon days and is more frequent than solar eclipses.
Lunar eclipse do not occur on every full moon night because the moon’s orbit is inclined to the Earth’s orbital path.
A lunar eclipse may be partial or total.
1.PARTIAL LUNAR ECLIPSE: When a part of Moon is hidden by the Earth’s shadow, it is called Partial Lunar Eclipse.
2.. TOTAL LUNAR ECLIPSE: When the entire Moon is hidden from view, it is called a Total Lunar Eclipse.
* Only certain portions of the Earth experience each eclipse for a short period because the Earth and the Moon are moving along their orbits.

In a lunar eclipse, the Earth moves between the sun and the moon and casts a shadow on the moon. Lunar eclipses can come in a variety of colors from deep black to rich shades of red. The red coloring comes from light from the sun that is filtered as it passes through the Earth’s atmosphere and is bent toward the moon. That light reflects off the surface of the moon and into our eyes on Earth. Lunar eclipses are only evident when the moon is passing through the Earth’s umbral shadow.