Woodpecker on Pitara Kids Network

Why can’t the Sun melt Snow?

Mon, 10 Feb 2003 13:20:47 +0000

There are some things in nature that have a great capacity to toss back or reflect a great deal of the sun’s light that falls on them. One of them is snow. Newly formed snow reflects about 90 per cent of the sunlight that falls upon it. This means that the sun is powerless to melt clean snow. And when snow does melt, it is not because of the sunlight. Snow does not melt on a spring day because of the sun’s heat. It melts because of the warm air from the sea.

Tree Rings tell many Tales

Thu, 30 May 2002 18:45:46 +0000

Examining ancient trees helps scientists get an amazing picture of Earth’s life, for trees are a record of their life time. By looking closely at the rings of a tree, scientists can not only tell how old it is; they can also tell you that in one summer in 1453 and again in 1601, there were freak cold spells.

Tree rings, when radiocarbon-dated give a glimpse of certain aspects of prehistoric times. But what is radiocarbon dating?

Aristotle can’t remain Ignorant!

Fri, 17 Dec 2004 02:54:54 +0000

The Greeks were a passionately curious lot. When Alexander the Great set off in 334 BC on the famous expedition that took him over the Hindukush into Tashkent and Kashmir, he was accompanied not only by navigators, guides and surveyors, but historians and philosophers as well.

Aristotle can’t remain Ignorant! [Illustration by Shinod AP]

Alexander had been taught by the philosopher Aristotle, and we are told that he ordered everyone throughout Greece and Asia who made their living by hunting, fowling, fishing, beekeeping and so on, to make sure that “Aristotle should not remain ignorant of any animal born anywhere.”

Dropping Trees from the Sky – Hydroseeding

Wed, 26 Jun 2002 02:49:55 +0000

Finally there is a simple solution to the growing problems of deforestation and the greenhouse effect – dropping millions of trees out of an aircraft.

Dropping Trees from the Sky [Illustration by Shinod AP]

The idea may sound bizarre but it has come from The Lockheed Martin Aerospace Company, USA. The company has proposed to transform equipments installed in huge C-130 military transport planes for laying carpets of landmines across combat zones, to plant trees in barren areas.

The Earth takes a Battering

Sun, 29 Sep 2002 14:09:00 +0000

During its life span, our planet has suffered the impact of close to 30 small planets, up to 10 miles in diameter and travelling 60 times the speed of sound. Each such impact releases about a thousand times as much energy as would be released if all the nuclear powers exploded all their present weapon stocks.

About 5,000 giant meteorities with diameters of more than a kilometre have hit the Earth over the past 600 million years, with an average strike rate of one per 120,000 years. Meteorites with diameters greater than 300 metres have hit the Earth once in every 10,000 years.