BTN: The biggest radio telescope in the world

NATHAN BAZLEY:

Australia is in the running for a project that could completely change what we know about the universe. It will be the most powerful telescope ever built — but it doesn't 'see' like you and I do. It's called a radio telescope and here's Alfie to explain how it works.

ALFIE TIEU, REPORTER:

Humans have always been fascinated by what's going on above them — in fact, astronomy is one of the oldest sciences. In the beginning astronomers used to just climb a hill and use their eyes and they came up with drawings like this. But then came a revolution — the telescope. They could see much further than ever before and the universe started to open up. Telescopes have been around for hundreds of years. This one in Sydney Observatory was built in 1874, but they were around long before that. They're called optical telescopes because they collect light using lenses and mirrors. They've told us a lot about space, but there are still things we don't know, especially in the far corners of the universe. That's so many billions of kays away that the light coming from there is really weak and hard to see. But light is only one type of energy. There are other types that are invisible, like radio waves. And that's why astronomers came up with these — they're called radio telescopes. This one is at Parkes in New South Wales and that huge white dish is an antenna. They're kind of like the antennas on your radio, but you won't be able to send text messages to aliens or tune into the Martian Top 40. Stars and galaxies send out radio waves, and some waves are stronger than others. A radio telescope collects them in the dish and the information goes into a computer. The waves are then used to make images like this. Astronomers can then see what objects far far away look like, and what they're made of. Amazingly, this helps them learn more about how the universe and life began. They even try to predict when some of the stars will die. A radio telescope also helps astronomers see through space dust which blocks ordinary telescopes. But if you think a radio telescope is pretty amazing — you ain't seen nothin' yet. This is the square kilometre array telescope, or SKA for short. A team of international astronomers wants to build a massive group of radio telescopes in a field and link them together electronically. There'd be about 3,600 antennas. And because they're all linked, they work together like one gigantic telescope. Australia is now one of two places picked as the possible site. If chosen, it will make us the leader in radio astronomy for the rest of the century, and home to the biggest and fastest telescope in the world! Maybe there is life out there, or maybe there are planets we haven't found. Who knows what scientists from around the world could learn from it!