People explore the universe in many ways: we build telescopes on the ground and in space; we send unmanned spacecraft to explore the solar system and beyond; we’ve landed on the Moon; and we may even go to Mars soon. Here are some examples of the search for knowledge beyond our planet in its many forms.

Peering into space

Astronomers are always looking for better ways to study the sky. Lots of things get in the way-gas and dust block our view, and some radio signals are too faint for us to pick up on Earth. Some creative new ideas include a mega telescope that will see farther than ever before. New technologies are also helping us to see past gas and dust to get a better view of faint and hidden galaxies.
People explore the universe in many ways: we build telescopes on the ground and in space; we send unmanned spacecraft to explore the solar system and beyond; we’ve landed on the Moon; and we may even go to Mars soon. Here are some examples of the search for knowledge beyond our planet in its many forms.

Peering into space

Astronomers are always looking for better ways to study the sky. Lots of things get in the way-gas and dust block our view, and some radio signals are too faint for us to pick up on Earth. Some creative new ideas include a mega telescope that will see farther than ever before. New technologies are also helping us to see past gas and dust to get a better view of faint and hidden galaxies.

© Canadian Heritage Information Network, 2003

Australian Square Kilometre Array

Artist's impression of the SKA station. An Australian Square Kilometre Array (SKA) concept proposal.

Centre for Astrophysics & Supercomputing

© Swinburne University of Technology


Radio telescopes usually consist of a dish that reflects radio waves to a sensor. The bigger the dish, the more powerful the telescope. But a dish can only be so big before it’s impossible to move it, or even build it.

Astronomers get around this problem by building many small dishes and making them work together as one big telescope. And this is the way they’ll build the world’s first truly giant telescope - the Square Kilometre Array (SKA). This will be a hundred times bigger and more sensitive than anything existing today. Rather than one huge dish, the SKA will be made of many small surfaces grouped together to make a telescope with a collecting area of a million square metres, or one square kilometre. Construction is expected to start in 2012.

The SKA will be able to look far enough back in time to see the formation of the Universe’s first galaxies. It could also track satellites and deep space probes, study ’space weather’, create images of the planets in our solar system, and help in the search for extraterrestrial intelligence (SETI).

Australia and Canada are among the 15 countries that are working tog Read More
Radio telescopes usually consist of a dish that reflects radio waves to a sensor. The bigger the dish, the more powerful the telescope. But a dish can only be so big before it’s impossible to move it, or even build it.

Astronomers get around this problem by building many small dishes and making them work together as one big telescope. And this is the way they’ll build the world’s first truly giant telescope - the Square Kilometre Array (SKA). This will be a hundred times bigger and more sensitive than anything existing today. Rather than one huge dish, the SKA will be made of many small surfaces grouped together to make a telescope with a collecting area of a million square metres, or one square kilometre. Construction is expected to start in 2012.

The SKA will be able to look far enough back in time to see the formation of the Universe’s first galaxies. It could also track satellites and deep space probes, study ’space weather’, create images of the planets in our solar system, and help in the search for extraterrestrial intelligence (SETI).

Australia and Canada are among the 15 countries that are working together to plan the telescope.

Eggs on legs

Australia is proposing one of the most "far out" ideas for the SKA: tens of thousands of 7-metre spheres laid out in patches across the landscape. The spheres, called Luneburg lenses, would look like an army of "eggs on legs."

Big orange balloon

Canada’s design is 60 giant reflectors, each one 200 metres in diameter. A reflector would be made of more than 1500 panels of ribbed steel-the kind used in supermarket roofing. The panels receive incoming signals and reflect them to a sensor suspended from a big helium balloon. Each panel can be steered to point the telescope at any part of the sky.

© Canadian Heritage Information Network, 2003

Australian Square Kilometre Array

Artist's impression of the SKA station. An Australian Square Kilometre Array (SKA) concept proposal.

Centre for Astrophysics & Supercomputing

© Swinburne University of Technology


CSIRO testing a Luneburg lens

CSIRO's Dr Peter Hall with a Russian Luneburg lens, during testing at CSIRO's Radiophysics Laboratory in Sydney.

Photo: David Smyth

© 1997-2002, CSIRO, Australia


(SKA)

Centre for Astrophysics & Supercomputing

© Swinburne University of Technology


Square Kilometre Array

Canada's idea for the Square Kilometre Array (SKA).

NRC-HIA's Dominion Radio Astrophysical Observatory (DRAO)

© NRC-HIA's Dominion Radio Astrophysical Observatory (DRAO)


The Milky Way is what we see of our own Galaxy from the inside - a thick band of stars and dust. It’s beautiful to behold, but it also blocks our view of the Universe beyond. To get a view of the Universe behind the Milky Way, astronomers can use radio waves, w hich travel straight through the dust.

With a system called the multibeam receiver, Australia’s Parkes radio telescope made the first picture of the sky in which the stars and dust of our own Galaxy didn’t get in the way. These radio waves come from cold hydrogen gas , the raw material for making stars. By looking at the gas rather than the stars we get a different picture of how matter is distributed in our Galaxy’s neighbourhood.

The multibream receiver was installed on Australia’s Parkes telescope in 1997. It lets us look for objects that put out no light at all, such as dark gas clouds. It also hunts for galaxies that other searches haven’t found-the ones hidden behind the Milky Way, very small dwarf galaxies, and galaxies with lots of hydrogen gas but few stars.

In 1998, researchers using the receiver showed that the Milky Way’s gravity is rip Read More
The Milky Way is what we see of our own Galaxy from the inside - a thick band of stars and dust. It’s beautiful to behold, but it also blocks our view of the Universe beyond. To get a view of the Universe behind the Milky Way, astronomers can use radio waves, w hich travel straight through the dust.

With a system called the multibeam receiver, Australia’s Parkes radio telescope made the first picture of the sky in which the stars and dust of our own Galaxy didn’t get in the way. These radio waves come from cold hydrogen gas , the raw material for making stars. By looking at the gas rather than the stars we get a different picture of how matter is distributed in our Galaxy’s neighbourhood.

The multibream receiver was installed on Australia’s Parkes telescope in 1997. It lets us look for objects that put out no light at all, such as dark gas clouds. It also hunts for galaxies that other searches haven’t found-the ones hidden behind the Milky Way, very small dwarf galaxies, and galaxies with lots of hydrogen gas but few stars.

In 1998, researchers using the receiver showed that the Milky Way’s gravity is ripping apart two of our neighbour galaxies-the Large and Small Magellanic Clouds. The receiver has also been used to find many pulsars - the collapsed cores of supermassive stars.

© Canadian Heritage Information Network, 2003

Parkes Radio Telescope

Parkes Radio Telescope.

CSIRO

© 1997-2002, CSIRO, Australia


Parkes Telescope multibeam receiver

Parkes Telescope multibeam receiver.

CSIRO

© 1997-2002, CSIRO, Australia


Our Galaxy and its Near Neighbours

This picture, made with the Parkes radio telescope, is centred on the South Celestial Pole and shows about a third of the southern sky. Upper left, our two nearest neighbouring galaxies, Large and Small Magellanic Clouds. Hydrogen gas, the raw material for making stars, is being sucked out of the Clouds by the gravitational pull of our own Galaxy, which stretches across the bottom of the picture. The different colours represent different intensities of the radio emission from the hygdrogen gas.

Image: B.S. Korabalski and the HIPASS team.

© CSIRO


Parkes Multibeam System.

What’s out there? It’s the question that everyone wants answered. And now, with the most powerful telescope of its kind in the world, Australian astronomers may be about to find out in their search for hidden galaxies. Even with a radio telescope as powerful as the one at astronomers can take a long time to search the sky. Many galaxies beyond our own are faint, and give out little light. Some are hidden by the stars and dust of the Milky Way. Astronomers find hidden galaxies by looking for radio waves that come from cool hydrogen gas, the stuff that stars are made from. But the problem in the past has been that the radio waves are so weak, that it takes a long time to find them. But now, a new multi-beam system, built for the Parkes telescope by CSIRO means that 13 pieces of the sky can be observed at once, instead of just one. “We can now look at parts of the sky and find galaxies that were not known before.” The multi-beam system is carrying out two major projects. Mapping galaxies all over the southern sky, and searching for galaxies behind the Milky Way. And already some amazing discoveries have been made, including the ripping apart of the magellanic clouds by our own galaxy by our own galaxy, the Milky Way. “Many of the observations show that its extremely likely that in about a million billion years time, the magellanic clouds will collide with our own galaxy, and when you have more than a hundred million solar masses of gas colliding with our own galaxy, that’s a lot of new stars to be made. A lot of new star formations.” Australian astronomers have found one hundred new galaxies behind the Milky Way, and about one hundred forty new pulsars. The new multi-beam telescope has been making new discoveries more than ten times faster than in any other survey anywhere in the world. Who knows what else they may find.

CSIRO, Australia

© CSIRO, Australia


Learning Objectives

The learner will:

  • Describe scientific and technological developments, past and present and appreciate their impact on individuals and societies
  • Describe how Canadians have contributed to science and technology on the global stage
  • Relate some of the current questions being investigated by cosmologists, and the technology being used, or proposed, to answer them
  • Develop enthusiasm and continuing interest in the study of science

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