The surfaces of valley glaciers are littered with rocks which have tumbled down the mountainsides. Other rocks are frozen into the sides and bottoms of glaciers. These rocks turn the glaciers into gigantic files, because, as the glaciers move, the rocks scrape away at the land and gouge our more and more rocks. When the ice melts, steep sided, U-shaped …

Diamonds are measured in Carats (not carrot). A carat weighs 0.2 grams. The largest fine quality, colorless diamond ever found was called “The Cullinan”. It was mined in South Africa and weighed 3,106 carats. It was cut into 106 jewels and produced the finest, largest gemstone ever, weighing 530.2 carats.

When American astronaut Alan Shepard couldn’t hold his pee any longer on their space mission in 1961, he was directed to do it in his suit, a new book has revealed. According to Tom Wolfe’s book ‘The Right Stuff,’ that’s what mission control said to Shepard during Mercury-Redstone 3, when the astronaut said he needed to urinate. Shepard did as …

Many waterfalls occur where rivers flow over hard rocks which overlie softer ones. The hard rocks resist erosion, while the softer rocks are worn away. The hard lip of the waterfall often overhangs the softer rocks and slabs of hard rock sometimes break off and crash downwards. In this way, waterfalls, like southern Africa’s Victoria Falls (whose African name means …

The ozone layer contains ozone molecules – O3 molecules – which are formed by the action of ultra-violet rays on atmospheric oxygen. This oxygen, which is O2, converts into O3 when UV rays fall on it. When these rays fall on the surface of the atmosphere, they are absorbed in the conversion of oxygen into ozone. As a result, ultra-violet …

Maximum and minimum temperatures are measured using thermometers mounted inside a wooden box with slits, called Stevenson’s screen, which is generally kept facing north. The maximum thermometer is mercury-in-glass – as the temperature rises, the mercury expands and moves freely up a constriction in the thermometer. When air temperature drops, the constriction prevents the mercury from flowing back due to …

In the 19th century, geologists could tell whether one rock layer was older or younger than another by the fossils they contained. But they could not measure the absolute ages of rocks until after the discovery of radioactivity in the 1890s. Radioactive substances, which are occasionally found in rocks, give off high-energy rays and decay (break down) at a fixed …

Sunset occurs when the upper edge of the sun — called the upper limb — sinks just under the horizon; sunrise occurs when the upper limb rises just above the horizon.

Stem cells, which hold the promise of new cell-based therapies to treat critical medical conditions, have to be effectively stored until it’s time to use them. The method is called cryopreservation: it freezes stem cells at temperatures below -150 o C, by immersing them in nitrogen vapour. But if the cells are to survive this process, they need to be …

Points or index refers to a figure indicative of the health of the stock market. The most widely used index is sensex or sensitive index which is based on weighted value of 30 numbers of most traded shares in the Mumbai stock exchange. Each stock has a percentage share in a total of 100 and affects the value of the …