The moon. The fifth largest satellite in the solar system and an estimated 4.5 billion year old. Apart from the sun, it is the brightest object in the sky, according to the BBC. The moon takes around 27 days to orbit (travel around) the earth and it is known as a solar eclipse when the moon passes between the sun and the earth. This can be seen on Earth as when the moon either fully or party covers the sun. Monthly, on average, the moon goes through eight phases (or stages) in which the appearance of the moon differs.
The phases of the moon depend on its position in relation to the Sun and Earth. As the moon makes its way around the Earth, we see the illuminated parts of the moon's surface at different angles. The moon is illuminated because it is reflecting the sun light. So the part of the moon facing the sun is lit up and the part facing away from the sun is in darkness. These changing shapes of brightness on the moon are what we call “phases”
Phases are seen differently in different hemispheres because the moon orbits near the equator of the Earth. The Northern and Southern hemisphere are upside down from each other so therefore we each see the moon at a completely different vantage point. Countries near the equator see the crescent moon shape like a smile.
The cycle begins with a New Moon, this occurs when the moon is in a position between the earth and sun. The Sun, moon and Earth are all in alignment with each other so only the back of the moon is being illuminated and this is the half we cannot see.
The next phase is the Waxing Crescent; the sun light reflection is becoming more increasing on the moons surface but is still less than half. It can always be seen after sunset low in the West. It does rise in the East after Sunrise but it is too close to the sun to be seen during the day. When the sunlight reflection does increase to half the moons surface this is known as the 1st Quarter or Half Moon. This means the moon is 90 degrees east of the Sun.
As the bright part of the moon gets bigger this is called waxing. The next stage is when the sunlight has increased to over half of the surface and is known as the Waxing Gibbous.
At a Full Moon the moon is 180 degrees from the sun and always comes about 2 weeks after the New Moon phase. The Earth, moon and Sun are again in alignment like during a New Moon but the moon is on the opposite side of the Earth this time so its entire surface is illuminated by sunlight. It’s the only moon phase that shines throughout the whole night.
Waning is when the bright part of the moon starts to get smaller. Therefore the next stage is called the Waning Gibbous. This moon rises in the east after sunset and sets in the West after dawn.
When the moon reaches 90 degrees west of the Sun the opposite half of the surface that was bright during the 1st Quarter phase is now illuminated. This phase is called the Last Quarter. As the illumination starts to decrease to less than half this is called the Waning Crescent. Then again back to a New Moon. The whole cycle is known as the Lunar month and takes 29.5 days to be completed.
Where we have physical phases of the moon, there are also many beliefs, both cultural and historic about its meaning. In Greek mythology, the Romans believed the moon to be ‘Luna’ – the goddess of heaven. In ancient Egypt, the moon was regarded as very important as a night replacement for the sun. Still today, a significant festival celebrated in China is the ‘Moon festival’. This is a celebration of the moon which can be dated back to thousands of years originating as a celebration of their own lives or sending their best wishes to family who are not near them.
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