What is Space ? | Explore it !

Space holds many secrets. It contains places where human beings can be stretched into spaghetti shapes, or boiled, or frozen solid: that's why astronauts wear protective clothing in space. Welcome to a mysterious and endlessly fascinating - world.

Is that space?

On a cloudless night, you can see thousands of stars. Space is the name we give to the huge empty areas in between the atmosphere of stars and planets. Apart  from the odd rock, space is sprinkled only with dust and gas.

What is space? When people think of space, they think of:

v                    Weightlessness - everything floats as if there's no gravity.

v                      Nothingness - vast areas of space are completely empty.

v                      Stars -Stars every star is a burning ball of gas. Our Sun is a star.

v                            Astronauts - people who explore the world beyond our Earth.

v                     Rockets and satellites - are what scientists use to explore space.

v                           Silence - there is no air in space, so there is absolutely no sound.

Why is space so dark?

 Space is black because there is nothing there to reflect light. From space, Earth looks lit up because light from our Sun reflects off sea, and land, and the particles in our atmosphere.

Where does space begin?

Earth is cloaked in a thin layer of gases the atmosphere. Outside this atmosphere is space, where there is no air to breathe, or to allow wings to fly, and where nobody can hear you scream.

Fading away

 Our atmosphere does not just end suddenly - it fades gradually into space.

Space badge

The American space agency NASA awards astronaut wings to service personnel and civilians who have flown more than 80 km (50 miles) above the Earth's surface.

Stargazers

People have looked at the night sky for thousands of years. This study is called astronomy. Around - this tool is called a telescope. 400 years ago, a special tool was invented to make the task easier.

Before the telescope

People were shocked when Polish astronomer Nicolaus Copernicus suggested in 1543 that Earth was just another planet and the planets orbited (went around) the Sun. They had believed Earth was at the centre of the Universe.

The Italian astronomer Galileo Galilei built a simple telescope in 1609 and proved Copernicus had been right. He discovered Venus had phases (like our moon), he saw Jupiter's moons, and he spotted mountains on our moon.

An eye in space

Now we have telescopes in space, most famously the Hubble Space Telescope (HST), which floats 600 km (375 miles) above Earth's surface. It is operated by remote control from Earth. Hubble, a 20th-century telescope. Hubble is about the size of a school bus. Hubble has taken incredibly detailed images, such as this one of the death of a star. Hubble is monitored by the Flight Operations Team (FOT) at the Goddard  Space Flight Center in Greenbelt, Maryland, USA. The team use computers to constantly check all is running well. The James Webb Space Telescope (JWST) is currently being planned to replace Hubble in 2013. It will see farther and more clearly than Hubble.

Observatories

Light is constantly reaching us from space, and one way astronomers learn about space is by studying this light. To do this effectively, an astronomer needs a telescope and a clear, night sky.

Island observatory

The world's largest light detecting telescopes are the twin Keck telescopes. These are on the summit of Mauna Kea, a dormant (sleeping) volcano in Hawaii. They both contain mirrors that are 10 m (33 ft) across.

A better view

The Royal Greenwich Observatory moved its telescopes three times because pollution clouded their view. Originally in Greenwich, near London, England, the telescopes ended up in the Canary Islands, 2.3 km (1.4 miles) above sea level.

Space telescope

Scientists use the Chandra X-ray telescope to study black holes and exploding stars. A 'Finderscope is used to line up the main telescope

What's in a name?

A telescope with a lens or mirror, called an optical telescope, gathers more light than the human eye. Large telescopes use mirrors: the larger the mirror the more it can see. Telescope projects are often given grand names... there's the Very Large Telescope, the Overwhelmingly Large Telescope, and the Extremely Large Telescope.

Radio telescopes

Invisible radio waves surround us. They also reach us from space, and large dishes are used to pick them up, day and night, to help astronomers learn more about space.

 So do the dishes “ listen’’ to space ?

 No. Radio astronomers do not listen to noises .Sound  waves  do not pass through space . the dishes pick up radio waves , a receiver measurers them , and a computer turns this information into a picture.

 Tilt and Learn

Radio dishes are designed to tilt and move around , so radio astronomers can point them at the bit of space they want to study . Also, as the earth turns , radio dishes need to move in order to follow one spot in the  sky .the movement , which are controlled  by computer , are very precise.

Big in every way  

The Very  Large  Array (VLA) in New Mexico has 27 dishes , each 25 m (85ft) in a diameter .Used individually or together to sweep the sky for signals , they rest on tracks and can be over 36 km     (22miles)  !

Did you know ?

·         Astronomers  didn’t  discover radio waves from space until 1932.

·         The  First  telescope  invented  by  Hans Lippershey  in  1608.

·         Experts believe that  our universe its under 14 BILLION years old.