The James Webb telescope reaches its final destination in space, a million miles away

The James Webb Space Telescope, the most powerful telescope ever built, has reached its final destination in space. Now comes the fun part.

Thirty days after its launch, the tennis court-size telescope made its way into a parking spot that's about a million miles away from Earth. From there, it will begin its ambitious mission to better understand the early days of our universe, peer at distant exoplanets and their atmospheres and help answer large-scale questions such as how quickly the universe is expanding.

"Webb, welcome home!" NASA Administrator Bill Nelson said in a statement Monday after the massive telescope's final course correction.

"We're one step closer to uncovering the mysteries of the universe. And I can't wait to see Webb's first new views of the universe this summer!"

Controllers expect to spend the next three months adjusting the infrared telescope's mirror segments and testing out its instruments, added Bill Ochs, Webb project manager at NASA's Goddard Space Flight Center.

"We are now on the verge of aligning the mirrors, instrument activation and commissioning, and the start of wondrous and astonishing discoveries," Ochs said.

JWST, as the telescope is called, is more sophisticated than the iconic Hubble Space Telescope and will be capturing pictures of the very first stars in the universe. Scientists say it will also study the atmospheres of planets orbiting stars outside our own solar system to see if they might be habitable — or even inhabited.

The giant telescope can do this, in part, because it looks at longer wavelengths of light than Hubble could.

"The very first stars and galaxies to form are hurtling away from Earth so fast that the light is shifted from visible wavelengths into the infrared. So the Hubble telescope couldn't see that light, but JWST can," NPR's Joe Palca explained.

The revolutionary telescope will remain in a special orbit around a point in space known as Lagrange Point 2, or L2 — a point that will help keeps its position stable relative to Earth and the sun. Being in that spot protects it from big swings in temperature and allows the JWST's giant sun shield to block heat coming from the sun. The telescope must maintain constant, supercold conditions — minus 370 degrees Fahrenheit — for the instruments to function properly.

In its final form, the telescope is about three stories tall with a mirror that's 21 feet across — much too big to fly into space fully assembled. Instead, it was folded into a rocket and painstakingly unfurled by teams sending commands from Earth. Though the monthlong process was a nerve-wracking one, it appeared to have been completed flawlessly.

The undertaking cost roughly $10 billion and has been in the works since the late 1980s. Its first cosmic images are expected to be released to the public this summer.