Saturday 21 November 2015 Terry Cuttle explained the secrets of Gravitational Tides both here on Earth and elsewhere in the Solar System and Universe.
Gravitational tides by Terry Cuttle - November
What do the volcanoes on Io and the daily rise and fall of the Earth’s oceans have in common? They are both caused by gravitational tides. To any astronomer, the tides in Earth’s oceans appear simple enough. They are driven by the Sun and the Moon so should be easy to explain and predict. So why are there two tides per day when there is only one moon, and why do the tides not arrive at the times expected from knowledge of the movements of the Sun and Moon and with such a wide variation of the tide height at different places?
Terry Cuttle is a retired engineer and past president of the AAQ. He is especially known in the astronomical community for his interest in observing and photographing transient astronomical phenomena, especially eclipses. The ocean tides bring together Terry’s passion for astronomy and daytime pursuit of sailing in Moreton Bay.
Terry will describe the astronomical forces driving the ocean tides, reveal the reasons behind the tides unusual and unexpected behaviour and explain tidal prediction methods. But tides in Earth’s oceans are only part of the story. Gravitational tides have a surprisingly major impact on the planets, moons and other bodies of the Solar System as well as impacts on the Milky Way and its satellites and out into the universe beyond.