Partial eclipse 02 OCT (tomorrow)

[Climategirl]

Over half of the sun will disappear from British skies on 3 October 2005. It will be gone for a few hours until the moon moves out of the way and stops blocking the sunlight. Make sure you see it!

From Britain, the sun will be nibbled away by the moon from about 07:50UT (08:50BST). By 09:00UT the maximum partial eclipse will occur when about 60% of the suns face will be covered. It will then be slowly uncovered until the moon leaves the sun at 10:15UT.
Further South, the path of the moons shadow, whish is over 162km wide, runs though Spain, across Africa and terminates in the Indian Ocean. Viewers in this path will see the moon sit right in the middle of the sun surrounded by a shimmering halo of sunlight. Instead of a total eclipse, it will be an annular eclipse. It occurs when the moons orbit takes furtest from Earth and Earth simultaneously draws closer to the sun, so the moon appears too small to completely cover the sun.

Ring of fire
The moon will slip 'inside' the sun over the Atlantic at about 08:45UT and end in the Idian Ocean at about 12:15UT. from any one place, the longest the moon will appear to stay within the disc of the sun will be just over four and a half mintues. On this path of annularity, the moon will cover about 95% of the sins syrface and should cast a noticeable twilight on the surroundings. The sky only appears to darken when 90% of the sun is covered. Nevertheless, it is still dangerous to look at the sun.
A solar eclispe occurs when the moon is directly over the sun and the Earth. "The moon is very different from the sun and much closer to us, but due to one of the most remarkable coincidences in astronomy, it appears to be the same size in the sky as the sun does. The moon is about four hundred timess smaller than the sun and coincidentally enough, it happens to be four hundered times closer to the Earth" The sizes of the sun and the moon seem o change over time. Sometimes the moon appears a bit bigger than the sun, and sometimes a bit smaller. This is because neother the orbit of the moon around the Earth or the orbit of the earth around the sun is completely cirular. When the moon is at its furthest from the earth it appears small, just as hills or buildings appear small when seen far away, When the moon is nearer the earth it appears bigger. The same applies to the sun as the earth moves nearer or further away from it. The moon can appear to up to 10% smaller than the sun, or 8% larger. If the moos looks smaller than the sun when the earth, moon and sun are in line, there will be an annular eclipse. If the moon appears larger than the sun, a total eclipse will occur. The larger the apparent size of the moon compared to te sin, the longer the time of totality, when the whole of the sun is covered. This earth moon sun line up can only happen at the new moon but an eclipse does not happen every new moon. The moons orbit around the earth is slighlt tilted to that of our planets orbit around the sun. The shadow of the moon will therefore miss the earth, and the clipse will not be visible to anyone standing on its surface,
A lunar eclipse will happen when the earth lines up between the sun and the moon. This happens at full moon but again, not at every full mon. As earth is bigger than the moon. As the earth is much bigger than the moon, the shadow it casts is much larger. The smaller moon will usually fit completely withinthis shadow and a lunar eclipse will be seen from anywhere on earth that can see the moon at that time. If the moon does not completely fit wihtin the earths shadow a partial eclispe will be seen,
The same celestial mechanics that line up the earth, moon and sun in a solar eclipse will often also produce a corresponding lunar eclipse, either two weeks later or two weeks earlier than the solar eclipse. This time is no different and there will be a partial lunar eclipse on 17th October at about 12:00UT (13:00BST), but unfortunately will nit be visible from the UK.

Eclipse Safety
Never look at the sun with your naked eyes, or point an optical instrument such as binoculars or telescopes at the sun. Permanent blindness can ensure. Only specially filtered telescopes are safe to look at the sun. Such instruments should be prepared by an expert astronomer. By far the safest way to view the sun is using pinhole projection. This system can be made from two pieces of whte card. Put a small hole approx 1mm wide in the centre of one of the pieces of card. Wiith your back to the sun, let the sun fall directly on the hole. Hold the other piece of card abour 20cm below the first and a msall upside down image of the sun will be seen. The method will not produce a very bright image, but shielding the second piece of card, or screen from the sun can refine it.
Filters such as solar viewers can be used to look at the sun with the naked eye.

[P.K.]

Just had to be cloudy in Reading didn't it.....

[Climategirl]

Clooooooooooooooooooooooud, Cloooooooooooooooooooud, Clooooooooooooooooud. I am NOT! amused!