The moon is part of our everyday lives. There have been songs, poetry and stories written about our moon. In the past, people thought there were people on the moon and we even see the face of ‘the man in the moon’. At different times of the year, the phases of the moon have been used to help people plant their crops and the moon’s gravity affects the tides of the earth’s oceans. Even baby sea turtles run to the light of the moon when they hatch. The moon is such a major part of existence on earth, but it will not be exactly the same forever. Would you be surprised to find out – it is leaving?
The moon that we look at each night is not the same size that our great great great grandparents saw. When they looked up to see the moon, it looked bigger. That’s because the moon was closer to the earth then.
Our moon was formed billions of years ago when there was a planetary collision with the earth from an object that was called ‘Theia’. The explosion resulted in the earth we have today and the creation of the moon. At that moment, the moon was really much closer to the earth. A day was only 2-3 hours long because the earth was rotating very fast. Some planets have many moons or ‘satellites’, but our earth has only one. The moon and the earth have been in a kind of silent ‘dance’ ever since they were created.
Both the moon and the earth have a gravitational pull and ewe are ‘pulling’ so much, that it causes a bulge in the earth and the moon. You and I can’t see the ‘bulge’, but scientists have been studying it for years. The process is causing the earth’s rotation to slow down and this allows the moon to drift away, ever so slowly. 620 million years ago, one day on earth was only twenty one hours instead of the twenty four we have today.
We have proof that the moon is moving slowly away. During one of the manned missions to the moon they left some technology there to help the scientists measure the distance between the earth and the moon. Through these studies, they have found out that each year, our moon is drifting away at 1-2 cm. This is causing our earth days to get longer by 1/500th of a second each century, as the rotation of the earth slows.
Now don’t be upset. The moon will still be with us for a long time. The fact is, the moon is not strong enough to be able to escape the earth’s gravitational pull completely. The moon is affected by the ‘solar tides’ of the sun and that has a tendency to want to push the moon closer to earth. Between both of these factors, scientists have said that the moon won’t leave us, it will just drift away a bit further. There are some scientists that have developed a theory that the moon will drift out only so far and then, due to solar tides, will be pushed back closer to the earth.
The effect of the moon becoming more distant will be so slow and gradual that it is believed that sea life as well as the ocean tides will adjust to the changes over millions of years.