Scientists have unveiled plans for a telescope that will put the retractable models favored by amateur astronomers to shame. The Square Kilometer Array (SKA) will use hundreds of antennae to form a super-model that can see farther than ever before. Here, an instant guide to the world's biggest telescope:
What is the SKA?
When completed, it will be a collection of around 3,000 dishes, each 15 meters in diameter, and tens of thousands of smaller receivers, all spread across an entire continent (see "Where will it be?" below). They'll be networked to form a "single monstrous machine" capable of picking up signals from across the universe. The combined area of all the antennae will be about one square kilometer — hence the name.
How can I look through it, then?
Sadly, it's not a telescope that allows humans to peer at the depths of the universe with the naked eye, but a machine to detect electromagnetic radiation from thousands of light years away. By superimposing electromagnetic waves picked up across various frequencies — a science known as interferometry — astronomers can effectively "see" across the universe.
Where will it be?
SKA will be headquartered in the U.K., at the Jodrell Bank Observatory in Manchester, but the telescope itself is likely to be built either in southern Africa or Australia — the only places big (and willing) enough to fit the tens of thousands of antennae. Its total budget is around $2.2 billion.
When will it start working?
SKA is scheduled to become operational in 2024, by which time engineers will have designed computers able to cope with the incredible amount of data. Scientists figure that SKA will require central supercomputers capable of 100 petaflops per second. That's equivalent to the processing power of about one billion PCs, and fifty times more powerful than our most advanced supercomputer.
How much data will it produce?
The dishes alone will produce 10 times the current global internet traffic. When you add smaller receivers, you're looking at a rate of data more than 100 times the current global internet traffic. If you're familiar with the numbers, that's about 160 gigabits of data per second, enough to fill about 15 million 64GB iPods every day.
Could it really help us discover aliens?
SKA says its instrument will be able to pick up airport radar on a planet 50 light-years away — if such a thing exists. Scientists figure there are habitable planets as little as 20 light-years away, and if civilization on any of them has developed to the extent of our own, the SKA will be able to find it.
What else will it do?
Astronomers hope it will help prove Einstein's theory of relativity by discovering gravitational waves, and allow them to peer back into astronomy's "Dark Ages," when the universe was newly created and forming itself into stars and galaxies.