At sunrise and sunset, we see the sun through a greater thickness of air because it is low in the sky. Therefore, we are looking at it across the earth’s surface rather than directly up into the sky. At these times, the sky often turns orange-red because the photons of red and orange light are scattered through the atmosphere around …

Oil tankers, the biggest ships, are so large that their decks could accommodate a hundred tennis courts each with four players.

Did you that the sea horse is the only true fish which swims in a standing up position, and not lying down as other fish do?

A majority of dye pigments are derived from metals. Red dye comprises mercury sulphide, cinnabar and vermilion, yellow dye uses cadmium, while blue dye is made from cobalt salts. Other colours are made from chromium, manganese, ferric oxide or zinc oxide. Black dye is non-metallic and is made from carbon, black ink or logwood. Most of the metallic dyes are …

Zumba is a cardio-fitness regime based on Latin rhythms developed by a former aerobics instructor Alberto Perez from Colombia. A Zumba class would span several Latin dance styles including Mambo, Salsa, Cumbia and Merengue. Another unique feature of a Zumba class is its party atmosphere unlike a typical aerobics class.

Wood becomes waterlogged when all its calls are filled with water. It can absorb water only up to about 30 per cent of its own weight. As it does so, the wood swells until it reaches “fibre saturation point” or its maximum volume. If further water is added, it will penetrate to the cavities of the cells, but no further …

The skeleton does two very important jobs. It holds the body up, and it protects the delicate organs of the body. When a baby is born, it has about 270 bones in its body. These are small and quite soft, and as the child gets older some bones fuse together, so that there are about 206 by the time the …

This question has many parts to it. We know, for example, that eventually our star, the Sun, will die and in doing so will destroy the Earth. The very distant future, then mens the end of the Earth, but this will not occur for many millions of years and need not concern us here. It has also been suggested that …

Camels do not store water in their humps, as it is commonly believed. The humps are actually reservoirs of fatty tissue. Concentrating body fat in their humps minimizes heat-trapping insulation throughout the rest of their body, which may be an adaptation to living in hot climates. When this tissue is metabolized, it acts as a source of energy and yields …

Some people believe that the appendix ‘catches’ things like fruit pips, and has to be removed when it is full. This is not true. In fact the appendix does nothing at all, and we would manage very well without it. So, what is the appendix? The appendix is a small tube at one end of a large intestine. It is …