2018: James Webb Space Telescope

Because it takes about 13 billion years for light to reach Earth from the most distant galaxies in the universe, those images provide a glimpse into the universe's past. A million miles above Earth, the James Webb Space Telescope will study the oldest light in the universe to understand how galaxies formed after the Big Bang.As cosmic objects move farther away, our view of their light shifts toward the red end of the spectrum; light from very distant objects is shifted into the infrared spectrum, which makes infrared telescopes like Webb ideal for studying the oldest objects in space.The more light telescopes collect, the more deeply they can see into the sky. Webb will collect a lot of light: Its 6.5-meter (21-foot) segmented mirror is too wide to fit on a rocket, so it will fold up like origami alongside a sun shield the size of a tennis court, both of which will unfurl once Webb reaches orbit.Webb has a projected lifespan of five years, but scientists hope it will last up to 10. However, repairs , like those that have kept its predecessor, Hubble, flying since 1990, will be impossible for Webb. "It's four times higher than the moon, so the day that it stops operating it's just going to stay there," says Ray Villard, news director for the Space Telescope Science Institute.Some scientists consider that a risky proposition . Webb's price tag has grown from its original $1 billion budget to about $8.8 billion, forcing NASA to take money from other projects, like the Wide-field Infrared Survey Telescope commercial flights to the International Space Station, to foot the bill.In response, researchers have tried to pack Webb with as many instruments for as many studies as possible — adding further expense. With Webb, space science is putting most of its eggs in one very expensive basket that can't be repaired if it breaks.