One of the finest documentaries I have watched in recent years was by the British space scientist Maggie Aderin-Pocock. It was called Do we really need the moon?
I like Maggie, she’s one of those tutors you wish you’d had at school, she’s just so good at getting you to understand a subject, and is just so good at making you feel at ease through her enthusiasm and energy. As well as being the Chancellor of our local university in Leicester, she can also be seen on the popular BBC space programme “The Sky at night”
This documentary was released about 12 years ago but is not available on BBC platforms at this moment. I have however included the link to YouTube where you can watch the programme in its entirety.
One of the fascinating facts, and one that had me questioning whether it was a contributor to global issues is that the moon is moving away from Earth at a rate of about 3.8 centimeters (1.49 inches) per year. This might not seem like a lot, but over billions of years, it sure adds up. Since the Apollo 11 landing on the moon on July 20th 1969 the moon has moved away from us by approximately 209 centimetres or 6.85 ft. That’s in just 55 years. The moon invariably has an effect on a number of factors here on earth, with the major one being its effect on the tides.
The moon’s gravitational pull is the primary driver of the tides on Earth. As the moon moves further away from Earth, its gravitational pull weakens, which in turn affects the tides.
Effects on Tides
- Weaker tidal forces: With the moon moving away, its gravitational pull on Earth’s oceans decreases, resulting in weaker tidal forces.
- Lower high tides: As the tidal forces weaken, the high tides will be lower than they would be if the moon were closer.
- Higher low tides: Conversely, the low tides will be higher than they would be if the moon were closer.
- Reduced tidal range: The tidal range, which is the difference between the high and low tides, will decrease as the moon moves further away.
Don’t panic though as these changes will occur gradually over an extremely long period. It’s estimated that the tidal range will decrease by about 1-2% over the next 100 million years.
These distances between earth and the moon are calculated quite accurately by a piece of space hardware placed on the moon by the crew of Apollo 15 in 1971. It’s called a retro reflector unit. When a high intensity laser is fired towards it from earth, the time it takes to reach the reflector and then be beamed back to earth is measured, and from this measurement they can give an extremely accurate reading of the current distance. This system is still in use to this day. It also features in the documentary.
I’m fascinated by everything lunar related as I was brought up during the space race and was very much around when all of this occurred. I’ve witnessed a space shuttle launch (STS-79) and long to head back and witness one of the many launches taking place now in this revival of space travel.
My favourite ever quote was the one that went so:
“Don’t believe the sky is the limit when there are footprints on the moon”
Adventure, exploration, breaking barriers and exceeding limits. Everything that the human race is capable and very good at doing.
And some people are just fantastic scholars at teaching the subject.
Maggie is one of those special individuals.
Stay safe. Shine.




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