Posts Tagged ‘Neap Tides’

11/04/2019 – Ephemeris – It’s a quarter Moon today. On the oceans the smallest difference between high and low tides.

November 4, 2019 Comments off

Ephemeris for Monday, November 4th. Today the Sun will be up for 10 hours and 3 minutes, setting at 5:27, and it will rise tomorrow at 7:25. The Moon, at first quarter today, will set at 12:10 tomorrow morning.

Today’s first quarter moon means that this tides caused by the Moon and Sun are pulling on the Earth at right angles which keeps the tides low. These are called neap tides. The Moon also raises higher tides than the Sun, even though the Sun is much more massive. But it’s much farther away. And that’s the reason. Tides are caused by the difference in gravitational pull from one side to the other of the Earth. The Moon, being much closer has a greater difference in gravitational force. Only when the Moon Sun and Earth are lined up do we have the highest tides which are called spring tides. Galaxies, held together by gravity, are easily distorted by the tidal force of other galaxies and pull off what are called tidal tails.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.


Spring and Neap Tides

Spring and Neap Tides explained. Credit (South Africa).

Antennae Galaxies

This ground-based image was taken by Robert Gendler and shows the two merging Antennae Galaxies (NGC 4038 and NGC 4039) and their impressive long tidal tails. Click on the image to enlarge.  Credit ESA.