Tres cool.
Look deep into nature, and then you will understand everything better" -- Albert Einstein
Telescopes to show universe soon after Big Bang
It may not be possible to travel back in time, but seeing stars and galaxies as they looked millions or even billions of years ago is no problem thanks to telescopes, the closest thing we have to time machines.
Now, astronomers are holding their breath to see what they'll observe and discover with a new generation of huge telescopes set to be built around the world.
Peering ever deeper into space and further back in time, the powerful devices will be able to show what the universe was like when it was just a few hundred million years old and emerging from a period of total darkness after the Big Bang.
"[We'll be] looking at the first generation of stars forming in the universe, which is kind of a cool idea: The time when the lights went on in the universe. There was no light before that time," said Daniel Fabricant, associate director of the Harvard-Smithsonian Center for Astrophysics.
His institution is one of several research organizations and universities developing the Giant Magellan Telescope, to be built in Las Campanas, Chile, by 2018.
Bigger is better in the world of reflecting telescopes, which rely on primary mirrors to collect light. The bigger the primary mirror, the more light it can gather and the fainter the objects astronomers can see.
The world's largest optical and infrared telescopes have primary mirrors that measure about 10 meters (32 feet) across. But the Giant Magellan Telescope will more than double that diameter, with a monster primary mirror spanning almost 25 meters (80 feet).
If the Magellan is the first new-generation star gazer to be built, it may not remain the record holder for long. Another consortium of organizations and universities is preparing to construct the aptly named Thirty Meter Telescope on the Mauna Kea summit in Hawaii, also scheduled for completion in 2018.
Trumping them all may be the European Extremely Large Telescope, dubbed "the world's biggest eye on the sky," which is to have a primary mirror 42 meters (137 feet) in diameter and is also scheduled to start operation in 2018. No site has been chosen, though Argentina, Chile, Morocco and Spain are being considered.
Astronomers hope these giants will fill in gaps in knowledge about key moments in the early days of the universe. See some of the amazing photos taken by the Hubble Space Telescope
"Right now, we can see to almost 13 billion years [back], but our best models tell us the age of the universe is almost 14 billion years, so it's this whole epoch when galaxies are actually first starting to form that we can't really see very well," said Elizabeth Barton, an assistant professor of astronomy at the University of California, Irvine, and a member of the Science Advisory Committee for the Thirty Meter Telescope.
he pictures will likely be spectacular. Despite being ground-based, all of the next-generation telescopes promise images several times sharper than those produced by the orbiting Hubble Space Telescope thanks to adaptive optics, technology that corrects for the "wiggling" of the Earth's atmosphere. Twinkling stars may be romantic to look at, but they're a big headache for astronomers trying to get a sharp picture.
One way to combat the distortion is to shoot laser beams into the sky to create fake stars and then measure how their appearance is changed by the atmosphere and take the appropriate counter-measures -- all at hundreds of times a second.
"You know what a perfect image looks like, you know what you observe, and then you know what you need to do to correct the image," Fabricant said.
"The idea is ... to have the mirror wiggle exactly opposite to take out the twinkling," Geha added.
Until the ground-based giants are built, Hubble's successor, the James Webb Space Telescope, will be helping to answer key questions about the universe. Webb is scheduled to be launched in 2014, about the time Hubble's mission will end.
Operating much farther from Earth and equipped with a primary mirror more than twice the diameter of Hubble's, Webb is designed to look deeper into space to see the earliest stars and galaxies, according to NASA.
Researchers on the competing projects say there's a certain rivalry about making the big discoveries but emphasize that the most important thing is that somebody makes them.
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