Category Science

How big is the sea?

The sea is absolutely huge! Salty sea water covers about two-thirds of our planet so there’s far more sea than land. The sea lies in five oceans — the Pacific, Atlantic, Indian, Arctic and Southern Oceans.

Amazing! The first person to set sail around the world was Ferdinand Magellan. He set off from Spain in 1519. Magellan died but one of his ships made it back three years later.

Which is the biggest ocean?

By far the biggest ocean is the vast Pacific. It alone covers a third of the Earth. At its widest point, between Panama and Malaysia, it stretches almost halfway around the world.

Is it true? The Arctic is the warmest ocean.

No. The Arctic’s the coldest ocean of all. For most of the year, it’s covered in ice.

Why is the sea salty?

The sea’s salty taste comes from ordinary salt. It’s the same stuff you sprinkle on your food. The rain washes the salt out of rocks on land, and then rivers carry it into the sea. The people in the picture are collecting salt left after sea water dries.

Picture Credit : Google

What are icebergs?

Icebergs are giant chunks of ice that break off the ends of glaciers and drift out to sea. Only about a tenth of an iceberg shows above water. The rest is hidden under the sea. This makes them very dangerous to passing ships and boats.

Amazing! In 1912 the luxury liner, Titanic, hit an Iceberg and sank in the North Atlantic. It was on its maiden (first) voyage from Southampton to New York.

Which was the biggest iceberg?

The biggest iceberg ever was seen near Antarctica. It was about the size of Belgium! The tallest iceberg was more than half as high as the Eiffel Tower in Paris.

Which is the longest glacier?

Glaciers are enormous rivers of ice that flow slowly down a mountainside. The Lambert-Fisher Glacier in Antarctica is over 600 kilometres long. It’s the longest glacier in the world. About a tenth of the Earth is covered in icy glaciers.

Is it true? Baby icebergs are called calves.

Yes. When a baby iceberg breaks off a glacier, it is called ‘calving’. Even smaller icebergs are called ‘bergy bits’.

Picture Credit : Google

How big is the Earth?

The Earth is shaped like a gigantic ball, slightly squashed at the top and bottom. Around its middle, where it’s fattest, it measures 40,075 kilometres. It would take you almost a year to walk right round the Earth, without a rest.

What are the continents?

The Earth’s rocky crust is cracked into several gigantic pieces and lots of smaller chunks. The large pieces contain the seven continents – Africa, Antarctica, Asia, Australasia, Europe, North America and South America. Which of the continents do you live on?

What’s inside the Earth?

The Earth is made up of layers of rock and metal. We live on the hard, rocky surface, called the crust. Below, the layers are so hot that they’ve melted and turned runny. The centre of the Earth is a ball of almost solid metal.

Amazing! People used to think the Earth was flat. If they sailed too far in one direction, they thought they would fall off the edge!

Picture Credit : Google

Where are the Poles?

The North and South Poles are at either end of the Earth. The North Pole is surrounded by the frozen Arctic Ocean. The South Pole is in the middle of icy Antarctica.

Amazing! The coldest place on Earth is Vostok in Antarctica. Here temperatures can plummet to an f-f-freezing minus 89°C.

Why are the Poles cold?

The Poles are the coldest places on Earth. They’re battered by blizzards and covered in ice and snow. The Poles are cold because the Sun’s rays hit them at a slant, so they’re spread out and very weak.

Is it true? Penguins live at the North Pole.

No. Penguins only live around the South Pole. But you might bump into a polar bear at the North Pole.

Who reached the South Pole first?

The first person to reach the South Pole was Norwegian explorer Roald Amundsen in December 1911. He beat the British team of Captain Scott by about a month. Exhausted and suffering from frostbite, Scott died on the way home.

Picture Credit : Google

How is a fossil made?

It takes millions of years to make a fossil. An animal dies. Its body sinks to the bottom of a lake. Sand and silt cover its body. The flesh rots away. Minerals seep into the bones and turn them to stone. The animal is now a fossil. The fossil is found.

How do we know about life in the past?

We find out about life in the past by looking for evidence. Fossils are one kind of evidence. They are the remains of living things that have been preserved. Objects made by humans, such as stone tools, are another kind of evidence.

Is it true? Plants can’t be fossilized.

No. Plants can become fossils, in the same way that animals can. By studying them we learn about the plants that once grew on Earth.

Who looks for prehistoric life?

People who look for remains of prehistoric animals, such as dinosaurs, are called palaeontologists. People who look for ancient humans are archaeologists. They find great things, such as bones, tools, buildings, jeweller and weapons.

Amazing! A sticky resin that oozed from pine trees trapped insects that landed on it. It hardened into a substance called amber. Prehistoric insects are perfectly preserved inside it.

Picture Credit : Google

When did modern humans appear?

Just over 100,000 years ago Homo sapiens appeared. The name means ‘wise man’. They were modern humans. In Europe they lived during the freezing Ice Age, a time when glaciers covered the land. The Ice Age ended 12,000 years ago.

Is it true? Homo sapiens have all died out.

No. All people on Earth today are members of Homo sapiens. If they had died out, like other kinds of early human, none of us would be here today!

Where did they live?

Homo sapiens first appeared in Africa, and from there, they spread out across the world. They lived in cave entrances, and in places sheltered by overhanging rocks. In the open they made huts from branches, covered with skins.

Amazing! People who lived during the Ice Age played musical instruments. They made whistles from bones, and drums from shoulder-blades.

Were they artists?

The humans who lived in Europe during the Ice Age were among the first artists. They painted pictures of horses, bison and deer on the walls of their caves. Bone and ivory were carved into figures of animals and people.

Picture Credit : Google