Why is the Sky Blue?

A blue over resort in Fife in East Scotland

Explains the scientific reasons behind blue skies on Earth. It contrasts Earth's atmospheric effects with those on the Moon, where the sky appears black due to a lack of atmosphere, and Mars, where a reddish-brown hue results from iron oxide dust.

Lunar Eclipse 28 September 2015

On 28 September 2015 there will be an total eclipse of the Moon, which will be viewable from many areas of the world. It will be an interesting sight and worth getting up at an unsociable hour to see it, especially since there won't be another total lunar eclipse until 2018. The Moon during a recent… Continue reading Lunar Eclipse 28 September 2015

How the length of a day changes over the year

The length of a solar day varies throughout the year, ranging from about 23 hours 59 minutes 38 seconds in mid-September to 24 hours 30 seconds around Christmas. This variation is caused by the Earth's elliptical orbit and axial tilt, affecting the Sun's apparent motion and leading to differences in natural time measured by sundials versus clock time.

Is There Anyone Out There? updated post

Thank you to everyone who has downloaded my books. One recent commenter pointed out that the links in the post point to the Amazon UK website and it was unclear how someone based outside the UK would download the books. I have therefore updated the post to make it easier for readers outside the UK to… Continue reading Is There Anyone Out There? updated post

Is There Anyone Out There ? An e-book about SETI

Updated 22 January 2026 Is there anyone out there?  The question of whether or not alien intelligent life exists elsewhere in the Universe has fascinated humankind for hundreds of years. Until relatively recently, this was merely the stuff of science fiction, but since the middle of the twentieth century astronomers have been able to seriously… Continue reading Is There Anyone Out There ? An e-book about SETI