In 2019 September 23 is the date of the September equinox and is also the first day of autumn (or the first day of spring if you're one of my readers in the Southern Hemisphere). In this post I’ll talk about the equinoxes and discus the commonly held view that they are the two days in… Continue reading The September equinox
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The Goldbach Conjecture
One of the oldest and most famous unsolved mathematical problems is the Goldbach conjecture. This is Every even number greater than 2 can be expressed as the sum of two prime numbers. This problem was first posed in 1742 by the German mathematician Christian Goldbach and nearly three hundred years later no one has managed… Continue reading The Goldbach Conjecture
12-13 August 2019 – the Perseids
The night of Monday 12/13 August will be the peak of the Perseids, one of the most famous prolific meteor showers Meteors (also known as shooting stars) are bright streaks of light caused by small lumps of rock or metal called meteoroids hitting the Earth's atmosphere at a very high speed (in the case of the… Continue reading 12-13 August 2019 – the Perseids
Apollo 11 lunar landing
20 July 2019 is the fiftieth anniversary of the first manned landing on the Moon. Mission Insignia of Apollo 11- Image from NASA On 21 May 1961 President John F Kennedy made the following address to the United States Congress: 'I believe that this nation should commit itself to achieving the goal, before this decade… Continue reading Apollo 11 lunar landing
Summer twilight
For those of us in the Northern Hemisphere we are at the time of year when there is the most daylight. In this post I’ll talk about the long summer evenings: not only does the Sun set later at this time of year but the amount of twilight, when the Sun has set but it… Continue reading Summer twilight
