The equinox March 20 2017

Now that we are in the month of March, for most of us in the northern hemisphere the worst of the winter is over, and it is only a few days until 21 March, the first day of spring.   There is a commonly held view that March 21 is the spring equinox and that the equinoxes are the two… Continue reading The equinox March 20 2017

The long summer evenings

This post talks about two interesting effects to do with the way it get dark after the Sun has set.  The first one, which anyone who has travelled to places lying at different latitudes will have seen, is that the closer you are to the equator the quicker it gets dark after the Sun has… Continue reading The long summer evenings

June 20- The Solstice

The June solstice will fall on June 20 or June 21 this year, depending on where you are in the world.  It is the longest day in the northern hemisphere and the day when the Sun is at its highest in the midday sky (see note). The origin of the word solstice is from the Latin words sol,… Continue reading June 20- The Solstice

The first day of spring

Now that we are in the month of March, for most of us in the northern hemisphere the worst of the winter is over, and it is only a couple of weeks until 21 March, the first day of spring. 21 March is an important date for other reasons, too. For one thing, it is used as the basis for the… Continue reading The first day of spring

How the length of a day changes over the year

Note March 25 2021 This topic is also available on YouTube https://youtu.be/Mx9AJJSKIL4 Most people are probably unaware of this but the length of a solar day, which is the natural day measured by the rising and setting of the Sun isn't  always 24 hours. It varies slightly throughout the course of the year and the days… Continue reading How the length of a day changes over the year