FIRST SUBMARINE

DID YOU KNOW THE FIRST SUBMARINE WAS POWERED BY JUST ONE MAN?

The first submarine to go into action was an american vessel called the Turtle (pictured above). It tried to attack a British warship in 1776, during the American war of independence. The Turtle was an egg shaped craft powered by one man, who sat inside and turned two handles connected to screw propellers outside. 

Manned by Sergeant Ezra Lee, the Turtles mission was to attach a mine to the warship's hull. The submarine worked well, but the bottom of the ship was lined with metal, preventing Sergeant Lee from attaching the mine.

IMPORTANT DISCOVERY

WHO MADE AN IMPORTANT DISCOVERY BY FEELING HIS PULSE?

The great Italian scientist, Galileo, made a famous discovery in 1581, while he was still a teenager. While attending services in Pisa Cathedral, a chandelier swinging in the air caught his eye. It seemed that the chandelier always took the same time to swing first one way and then the other, regardless of how far it swung each time.

As there were no accurate clocks in those days, Galileo measured the time of each swing by feeling his pulse and counting the beats. The answer was always the same. 

What Galileo had discovered was the pendulum. Using this, it proved possible at long last to build clocks which kept time accurately.

MIRAGE

WHAT IS A MIRAGE?

A mirage is a kind of optical illusion that occurs in hot, still weather. A pool of water suddenly appears in the distance. But on approaching, it seems to evaporate and there's actually no water at all. 

You may see these mirages on roads in the summertime. They also occur in deserts, sometimes complete with trees, and may trick a thirsty traveller into thinking that an oasis lies ahead. 

What you really see is simply a reflection, usually of the sky. The reason is that a layer of hot air near the ground acts like a mirror.

Have you ever experienced a mirage? tell me in the comments below.

CENTURY TOO SOON

WHO FIRST THOUGHT OF COMPUTERS?

The idea of the computer first occurred to British inventor Charles Babbage (pictured above) in about 1833. Others had made calculating machines before him, but Babbage was the first person to conceive of a machine that could be programmed to carry out different calculating operations, as a computer can.

Babbage designed a machine called the Analytical Engine (pictured above) that had the basic features of a modern computer. It was to be a mechanical computer, containing complex systems of shafts and gear wheels. However, only parts of the Analytical Engine were ever built. The engineering required to complete it was far beyond the techniques of the age, and Babbage died in 1871 without knowing whether his computer would work or not.

In fact, Babbage was far ahead of his time as the first computer, a British wartime decoder called Colossus (pictured above), was not built until 1943 and it used electronics, as mechanical operations were too slow. Colossus and all other computers since are really the descendants of Babbage's Analytical Engine.

FIRST ASTRONAUT

WHO WAS THE FIRST ASTRONAUT?

The first astronaut was Yuri Gagarin a Russian airman. He made one orbit of the Earth aboard the Vostok spacecraft on the 12th April 1961. The whole spaceflight lasted about 89 minutes. 

After his first ever spaceflight, Gagarin recalled his experience of his spaceflight by saying "The feeling of weightlessness was somewhat unfamiliar compared with Earth conditions. Here, you feel as if you were hanging in a horizontal position in straps. You feel as if you are suspended"

Sadly, Yuri Gagarin lost his life on the 27th March 1968, while on a routine training flight with flight instructor Vladimir Seryogin they crashed near a town called Kirzhach and died instantly.

SUN AND STARS

SUN AND STARS FACTS

1. The brightest star in the night sky is Sirius, in the constellation Canis, Major, the Great Dog.
2. It would take over a million Earths to fill a sphere the size of the sun.
3. Gases boiled off from the sun flow past the Earth, forming the solar wind. In a sense, we live inside the thin outer atmosphere of the Sun.
4. The Sun takes 220 million years to orbit the centre of the galaxy. So far, its been around the galaxy about 20 times. 
5. The temperature at the centre of the Sun is 15 million °C (30 million °F). A pinhead at this temperature would incinerate everything for several kilometers around.
6. Red supergiant stars are huge, but their outer layers are very rarefied - far thinner, in fact, than Earths atmosphere. The outer layers of a red supergiant are, in effect, a red hot vacuum.
7. About ten stars are born each year in our galaxy. That's almost one a month. But a similar number of stars die each year.
8. The farthest object visible to the naked eye is the Andromeda galaxy, 2.2 million light years away. 
9. When the Sun colapses in will retain its enormous mass but will have the approximate volume of the Earth. At this stage it is known as a white dwarf.
10.  The Suns mass is equal to about 333,060 Earths.

I hope you enjoyed these facts, check out the International Space Station live feed for some amazing views of the Earth: http://www.ustream.tv/channel/live-iss-stream

ICEBERGS

WHERE DO ICEBERGS COME FROM?

In polar regions, such as northern Greenland, ice extends right to the coast. In Antarctica ice shelves extend out to sea for great distances. periodically, icebergs break away and drift out to sea, slowly melting as they reach warmer waters.

Icebergs are a danger to ships, particularly because about eight-ninths of the ice is hidden below the water. Nobody can forget the fact that an iceberg sank the Titanic in 1912, and today patrols keep watch on the tall, jagged icebergs that drift into North Atlantic shipping lanes.

North Atlantic icebergs rise up to 394ft (120m) out of water, while icebergs from Antarctica are usually low and flat topped. The worlds largest iceberg came from Antarctica. It covered about 12,000 square miles (31,000 square KM) - an area larger than Belgium. 

Here's a link to USA today's report of 

the worlds largest iceberg which 

was spotted in 1956: http://usatoday30.usatoday.com/weather/resources/coldscience/2005-01-20-1956-antarctic-iceberg_x.htm

HOLLAND

HOLLAND IS UNUSUAL

There is a saying 'God created the world but the Dutch created Holland.' Holland (Netherlands) is a low-lying country where more than two-fifths of the land is below sea-level at high tide. Dutch engineers have reclaimed much of this flat land by building dykes (sea walls) to hold back the sea. The marshy areas behind the dykes are drained and turned into fertile farmland. By doing this the Dutch have gradually increased the land area of their country.

EARTH

IS EARTH A GOOD NAME?

Now we all know why the Earth is called Earth, right? because of the ground basically, dirt, soil, Earth. I'm not so sure that it's the best name for our planet though, for example, if an extraterrestrial being discovered our planet and had to name it simply by looking at it well, they would probably call it 'Ocean' or 'Water' thats presuming they can speak English of coarse.


BONUS EARTH FACTS

1. The Earth is slightly flat at the poles and bulges near the equator, the greatest bulge being  just  south of the equator.
2. The distance between the poles through the centre of the Earth is 7,900 miles (12,713KM)
3. The distance around the Earth via the poles is 24,860 miles (40,007KM)
4. The surface area of Earth is 196,951,000 square miles. it's weight is about 6,600 million million million tonnes.
5. The Earths crust can be as thick as 37-43 miles (60-70KM) under high mountains and as thin as 4 miles (6KM) under the oceans
6. The mantle beneath the crust is 1,802 miles (2,900KM) thick.
7. The Earths core, composed of mostly iron and nickel, is about 4,300 miles (6,920KM) across. Temperatures in the centre probably reach 5,000°C (9,032°F)   

SMOG

WHAT IS SMOG?

Smog is a word made from two other words: smoky fog. Its formed when smoke and poisonous gases mix with fog. Smog can be very dangerous, for example, in 1952 Britians biggest city, London, had a smog that caused 4,000 deaths. Another type of smog occurs in cities with lots of cars and is caused by exhaust fumes.