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What's next for the world's greatest telescope

The 60 Minutes story this week on the Hubble Space Telescope is called "Vast," and the numbers certainly justify the title.

For example, the sun that lights our planet every day is actually a yellow dwarf star of modest size, relative to the other 100 billion stars in our galaxy, the Milky Way.

Our galaxy itself is dwarfed by the estimated two trillion galaxies in our universe, bringing the total number of stars in the night sky to approximately 200,000,000,000,000,000,000,000.

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This image, created by the Hubble telescope, shows a cluster of stars in the constellation Sagittarius

NASA

This week on 60 Minutes, correspondent Bill Whitaker takes a closer look at the telescope that enables scientists to see into some of the farthest stretches of the universe — and to quantify just how enormous it is. Because Hubble continually improves our understanding of the cosmos, scientists don't undervalue the telescope's importance.

"I believe Hubble has been the single most transformative scientific instrument that we've ever built," NASA astrophysicist Amber Straughn tells Whitaker.

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The Hubble Space Telescope

NASA

60 Minutes first reported on Hubble 15 years ago this week. As correspondent Ed Bradley explained in the piece below, its cameras are so sophisticated they can capture light that began traveling through space billions of years ago. By the time that light finally enters the telescope and is transformed into an image, the picture it shows is of the universe as it was when the light began its journey in the unimaginably distant past. The telescope is, in essence, a time machine.

Hubble was launched in 1990, but Congress initially approved funding for its construction in 1977. It was named after Dr. Edwin Hubble, an American astronomer who, back in the 1920s, discovered that the universe is expanding. Now his namesake telescope has proven that it's expanding faster than scientists can explain.

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The iconic Horsehead Nebula, a dark nebula in the constellation Orion, as seen from the Hubble telescope

NASA

"It means that we don't understand gravity," Dr. Ed Weiler told Bradley. At the time, Dr. Weiler was the head of science for NASA and the person in charge of the Hubble Space Telescope; he later became director of NASA's Goddard Space Flight Center. "This implies there's some negative energy force, some anti-gravity that's actually pushing things apart. We don't understand it. It's not supposed to be there."

Bradley also spoke with Zoltan Levay, a NASA imaging specialist who applies color to Hubble's black and white images to stunning effect. Levay uses scientific data to determine what color the scenes are, billions of light years away, and says the images are representations of reality, just as a photograph is.

"We do adjust the color a little bit, partly just so it looks better, and partly so it also imparts the information that we'd like to get across," Levay said.

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A small section of the Veil Nebula — expanding remains of a massive star that exploded about 8,000 years ago.

NASA

Soon, Hubble's spectacular images won't be the only pictures we have of the distant universe. The much larger James Webb Space Telescope is scheduled to launch next year, and its camera should be able to detect light from the very earliest galaxies, giving us images from the beginning of time.

"The James Webb Space Telescope was specifically designed to see the first stars and galaxies that were formed in the universe," John Grunsfeld, an astrophysicist at the Goddard Space Flight Center, tells Whitaker this week. "So we're going to see that snapshot of when stars started. When galaxies started. The very first moments of the universe. My bet? There's going to be some big surprises."

Grunsfeld is also known as the Hubble repairman. As an astronaut, he flew three missions to mend Hubble and to upgrade its equipment. Hubble's replacement, however, won't have that option — the James Webb telescope will be too far away from Earth for astronauts to visit after launch.

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The James Webb Space Telescope will replace the Hubble telescope and is set to launch in 2019 

NASA

Because the new telescope is an infrared telescope, it will sense heat, and the Earth is too hot for it to orbit as closely as Hubble does today. While Hubble hovers 300 miles above Earth, the James Webb telescope will be one million miles out. For comparison, the moon orbits the Earth at just 238,900 miles.

"We're doing two grand experiments," Grunsfeld tells Whitaker in the 60 Minutes Overtime clip at the top of the page. "The Hubble Space Telescope, which was designed for extreme servicing, you know, we can fix everything. And the James Webb Space Telescope, where we can fix nothing. It has to work the first time. And it's a very complicated telescope."

But Matt Mountain, the telescope scientist for the Webb telescope says NASA has it figured out. If scientists can't physically fix the instrument in space, they'll have to rely on their ability to tweak it from the ground.

"The whole idea here is, when we send it out this incredible distance where we can't go out and fix it, we have many more knobs we can twiddle on the ground that we never had with Hubble," Mountain tell Whitaker in the clip above.

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An image of giant star cluster Omega Centauri, showing approximately 100,000 stars 

NASA

Still, with a price tag of $8 billion dollars, Mountain acknowledges that sending the Webb telescope into unreachable space successfully is a big gamble.

"So when you do hard things, sometimes you have to take risks, right?" Mountain says. "This is a uniquely powerful telescope, the most powerful space telescope humanity's ever launched…  In the end though, you're absolutely right. It's got to work by the time we get out there."

Images courtesy of NASA/ESA/STSCI

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