What is a Distrail?
A distrail is the clear path through a cloud formed in the wake of an aircraft. Distrails form because the aircraft turns the water droplets…
Tag: shadows
Why does the Gnomon on a Sundial Point South?
The pointy bit of a sundial is called a ‘gnomon’. It is the part that casts the shadow and in the northern hemisphere it points…
Which Way Are We Looking?
Which direction are we looking in the picture above? Spoiler alert… answer next… Answer: 1 Point for W. 2 Points for WNW. The snow has…
Which Way Are We Looking?
Two questions today. I took this picture yesterday. Which direction are we looking? And a tougher one: what sign is there in this picture that…
How to Read Water – New Animation!
Here is the first of a short series of animations that I will be publishing over the coming weeks. Hope you enjoy!
Sand Patterns, Shadows and Camel Balm
I recently got back from a brief work trip to the United Arab Emirates. Whilst there I visited Dubai, Sharjah, Ajman and Fujairah and spent…
22 Degree Halo and Contrail Shadow
My thanks to Alan Gibson, urbane forager and regular contributor to this blog, for another great image. In this picture we are looking at two…
The Colour of Water
The colour of water is determined by: A) What’s under it. B) What’s in it. C) What’s on it. D) And by light levels and…
A Painting Puzzle
My thanks to Sebastien from Leipzig, Germany, for sending in this photo of a painting in the Museum of Communism in Prague. Have a good…