The Moon has been a source of fascination to millions of people for centuries; before we had the technology to get us there, its mystery and awe was something to be revered and worshipped.
Following the success of space exploration that started in a big way during the 1950’s, whilst it is now possible to land on the Moon, does this make it any less mysterious and should it still be revered as something really rather special?
Has our knowledge of this unique satellite increased or decreased? Just what do we know about the Moon and what is the difference between the dark side and the far side?
A few factoids:
- The diameter of the Moon is 3,474 km or 2,159 miles (Earth is 12,742km or 7,918 miles)
- The surface area of the Moon is 37.9 million sq km or 14.6 million sq miles (Earth 510 million sq km or 197 million sq miles)
- Gravity on the moon is 17% of that on Earth
- It was formed approximately 4.5 million, million years ago and is the same age as Earth
- It is not a solid rock but is believed to have a liquid iron outer core
- The temperature recorded in a crater near the North Pole read minus 415°F
- The ‘Outer Space Treaty’ prevents anyone from staking a claim on it and allows any country to explore it for peaceful reasons only
- The Moon is the Earth’s only natural satellite and is the 5th largest satellite in the solar system
Its method of creation is still unknown although the most likely theory is a giant impact when something the size of Mars hit the new born Earth giving Earth its tilt and sending masses of debris into space, one piece of which was the Moon.
It was only when technology became available that the Space Race between the USSR and the United States moved up a gear in 1957 and it was the Russians who won the first victory launching their Luna 2 Mission, the first manmade object to be sent into space that crash landed on the Moon on 13 September 1959.
The rest as they say is history with America’s first man on the Moon, Neil Armstrong on 21 July 1969 and the last journey to the Moon was Apollo 17 in December 1972.
But to return to my question about the far and dark side, many believe they are one and the same and there have been countless films about the mysteries of the dark side. To dispel the notion there is anything sinister going on up there, the far side is the side of the moon we cannot see from Earth, it is permanently turned away from us; and the dark side refers to the North and South Poles that are in darkness most of the time.
The far side was first seen by human eyes when Apollo 8 orbited the Moon in 1968. There has been no ground exploration to date.
Photographs show it to be extensively battered with far more craters than the near side, suggesting there have been significantly more impacts and collisions on that side of the Moon.
The confusion with the dark side may have arisen due to the far side’s inability to receive radio waves from Earth so there is no way to communicate.
But why can’t we see the far side, why doesn’t the Moon turn?
That is due to the tidal forces coming from Earth: ‘tidal locking’ or ‘captured rotation’ means that the Moon is stopped from turning but due to its libration it gently rocks back and forth so we occasionally get to see a little bit of the far side (just over 9%).
So other than being slightly more battered, the far side of the Moon is not so very different from the near side.
No, it’s the dark side that is creating a bit of a stir amongst scientists: the North and South Poles are in darkness virtually all the time and it is these areas along with other sites known as Dark Mantle Deposits (DMD) where ‘water frost’ has been found in the shaded soil.
It is the discovery of water vapour that leads to the possibility of life support; not only can the water be used in its original form but by separating it into oxygen and hydrogen, it can then be used for creating a breathable atmosphere and fuel.
Other chemicals found in shaded soils include hydrogen, atomic mercury, carbon monoxide and calcium magnesium.
Additionally, these dark areas act as a shield against cosmic rays and solar flares, so would be the ideal place to build a Moon base.
Due to the colossal cost of space exploration, the next journey to the Moon is unlikely to happen before 2015, but the likelihood is that by then a space station will have been built here on Earth and will be ready to transport (albeit in Ikea flat pack form) out to the Moon.
So as usual, the books and films have been predicting where our future lies; remember ‘Space 1999’? Perhaps we are now looking at Space 2099 as a distinct possibility.