New Era of Exploration

This past July, NASA released a series of spectacular images. One showed a sea of sparkling stars shining through a craggy cloud of gas and dust. Another presented a trio of swirling galaxies, collections of gas, dust, and millions of stars and their solar systems. Yet another showed a dying star ringed by what looks like a fiery halo. These were the first full-color photos taken by the new James Webb Space Telescope—and the most-detailed snapshots of space ever seen. “Every image was just incredible and beyond what I had ever imagined,” says Stefanie Milam, a planetary scientist at NASA’s Goddard Space Flight Center in Maryland.

Milam is one of thousands of scientists, engineers, and technicians from around the world who helped create the Webb telescope. This $10 billion project took more than three decades of planning and preparation. That included figuring out how to fold the massive observatory like origami so it could fit inside a rocket. (To learn more about the creation of Webb, see "Portal to the Universe,” Science World, September 17, 2018.)

This past July, NASA released a series of stunning images. One showed a landscape of sparkling stars. They were shining through a craggy cloud of gas and dust. Another presented three swirling galaxies. Each holds millions of stars. And another showed what looks like a fiery halo around a dying star. These were the first full-color photos taken by the new James Webb Space Telescope. And they’re the most-detailed snapshots of space ever seen. “Every image was just incredible and beyond what I had ever imagined,” says Stefanie Milam. She’s a planetary scientist at NASA’s Goddard Space Flight Center in Maryland.

Milam helped create the Webb telescope. So did thousands of other scientists, engineers, and technicians around the world. This $10 billion project took more than three decades to plan and prepare. That included finding a way to put the massive observatory inside a rocket. It had to fold like origami to fit. (To learn more about the creation of Webb, see "Portal to the Universe,” Science World, September 17, 2018.)

On December 25, 2021, Webb was finally launched into space. Over the next month, it journeyed 1.5 million kilometers (1 million miles) away from Earth toward its target destination. As it traveled, the telescope slowly began to unfold and come online. “It is the most complex space telescope ever launched,” says Milam. The long wait to find out if the mission would be a success was nerve-racking, she adds. By late January 2022, Webb was orbiting the sun in lockstep with Earth, fully expanded and ready to switch on. Everything had worked perfectly!

The images the telescope has captured so far are not just beautiful—the high-resolution pictures also showcase parts of our universe that were previously out of view. “There are things we are observing with this telescope that we have never been able to study before with this amount of detail,” says Milam. And she and other researchers are just getting started.

Webb was finally launched into space on December 25, 2021. Over the next month, it traveled 1.5 million kilometers (1 million miles) away from Earth toward its destination. Along the way, the telescope slowly began to unfold and come online. “It is the most complex space telescope ever launched,” says Milam. Scientists had to wait to find out if the mission would be a success. That was nerve-racking, adds Milam. By late January 2022, Webb was orbiting the sun in line with Earth. It was fully expanded and ready to switch on. Everything had worked perfectly!

The telescope has already captured many images. These high-resolution pictures aren’t just beautiful. They also showcase parts of our universe that we couldn’t see before. “There are things we are observing with this telescope that we have never been able to study before with this amount of detail,” says Milam. And she and other researchers are just getting started.

Webb is the largest telescope ever sent into space (see Space Telescopes: Then and Now). Its enormous gold-coated mirror gathers and concentrates infrared light—light invisible to the human eye but detectable as heat. The light shines onto a camera at the center of the telescope, which captures images of faraway objects in space (see Inside Webb). To create Webb’s stunning photos, scientists must replace the infrared colors with visible ones that our eyes can see. Often, they’ll use color coding to help convey information about the objects in the image like their temperature, chemical composition, or density.

NASA released Webb’s first photos to the public mainly to demonstrate the telescope’s capabilities. Going forward, scientists will use the telescope to answer some big questions about our universe. “In the coming year, we will start to see the Webb telescope really rewriting the textbooks of astronomy,” says Matthew Greenhouse, the NASA project scientist responsible for Webb’s science instruments.

Webb is the largest telescope ever sent into space (see Space Telescopes: Then and Now). Its huge gold-coated mirror gathers and concentrates infrared light. This light is invisible to the human eye, but it’s detectable as heat. The light shines onto a camera at the telescope’s center. The camera captures images of faraway objects in space (see Inside Webb). To create Webb’s stunning photos, scientists must replace the infrared colors. Instead, they use colors that our eyes can see. Often, they’ll use color coding to reveal information about objects in the image. For example, colors can show temperature, chemical composition, or density.

NASA released Webb’s first photos to the public. The space agency wanted to show what the telescope could do. Now scientists will use the telescope to answer some big questions about our universe. “In the coming year, we will start to see the Webb telescope really rewriting the textbooks of astronomy,” says NASA project scientist Matthew Greenhouse. He’s responsible for Webb’s science instruments.

Webb’s main mission is to help scientists learn more about how the universe began. The universe is about 13.8  billion years old, and its origin is mysterious. “Traveling back in time is the stuff of science fiction,” says Greenhouse. “But looking back in time is something that we can actually do in astrophysics.” This branch of science applies physics, math, and chemistry to study astronomical objects and phenomena.

The universe has been constantly expanding since its birth during the big bang—an event that caused all the matter in the universe to explode outward from a single point. The first galaxies began to form a billion years later. Light from these faraway ancient galaxies is still traveling toward us through that expanding space. As light travels through space, it stretches. Its wavelength—the distance between two identical points on a wave—increases until it becomes infrared light.

Webb’s main mission is to help scientists learn more about the universe’s beginning. The universe is about 13.8 billion years old, and its birth is mysterious. “Traveling back in time is the stuff of science fiction,” says Greenhouse. “But looking back in time is something that we can actually do in astrophysics.” This branch of science uses physics, math, and chemistry to study the universe.

The universe was born during the big bang. This event caused all the matter in the universe to explode outward from one point. Since then, the universe has been constantly expanding. The first galaxies began to form a billion years after the big bang. Light from these faraway ancient galaxies is still traveling toward us. As it travels through that expanding space, light stretches. Its wavelength increases until it becomes infrared light. Wavelength is the distance between two identical points on a wave.

Webb was designed to detect the faintest infrared light given off by the most distant galaxies. This allows scientists to look far back into the universe’s past. The light from these galaxies has been traveling toward us for hundreds of millions of years. This means the telescope will capture images of these galaxies as they appeared hundreds of millions of years ago. Researchers hope the telescope will allow them to better understand how the universe evolved, explains Greenhouse. “And that could help us figure out what the future of the universe will be.”

The farthest galaxies give off the faintest infrared light. Webb was designed to detect that light. This allows scientists to look far back into the universe’s past. The light from these galaxies has been traveling toward us for hundreds of millions of years. So the telescope will capture images of these galaxies as they appeared hundreds of millions of years ago. Researchers hope the telescope will allow them to better understand how the universe evolved, explains Greenhouse. “And that could help us figure out what the future of the universe will be.”

In addition to learning about the history of the universe, scientists also plan to use Webb to take a closer look at other planets—both in our solar system and around faraway stars. Webb has already snapped one of the clearest views of Neptune, revealing the planet’s faint rings and moons.

Webb will help scientists learn about the history of the universe. But it will also help them take a closer look at other planets. They’ll use it to study planets in our solar system and around faraway stars. Webb has already snapped one of the clearest views of Neptune. It reveals the planet’s faint rings and moons.

Researchers will also use Webb to peer into nebulae—dark, dense regions of interstellar dust and gas where stars are born. Marcia Rieke is an astronomer from the University of Arizona who led the team that built one of Webb’s infrared cameras. One of her favorite Webb pictures so far is of the Carina Nebula, about 7,500 light-years from Earth. A light-year is the distance light travels in one year, about 9.5 trillion km (5.9 trillion mi). “The image is so beautiful and reveals dramatic details of how new stars form,” says Rieke.

Building the Webb telescope was a challenge unlike any NASA had ever undertaken. Now that it’s out in space, it can finally do what it was designed to do. “It’s kind of like sending a kid away to college,” says Greenhouse, who joined the project in 1997. “It’s an emotional thing because that phase of life is over. Now the kid is a million miles away, and it’s not coming back.”

Webb is expected to operate for the next 20 years—or more. Greenhouse is excited to see what the telescope will show us. “It’s giving us our first high-definition view of the universe,” he says, “and it’s going to be fantastic.”

Researchers will also use Webb to peer into nebulae. Stars are born in these dark, dense regions of interstellar dust and gas. Marcia Rieke is an astronomer from the University of Arizona. She led the team that built one of Webb’s infrared cameras. So far, one of her favorite Webb pictures is of the Carina Nebula. It’s about 7,500 light-years from Earth. A light-year is the distance light travels in one year, about 9.5 trillion km (5.9 trillion mi). “The image is so beautiful and reveals dramatic details of how new stars form,” says Rieke.

Building the Webb telescope was a huge challenge. NASA had never done anything like it before. Now Webb is out in space, and it can finally do its job. “It’s kind of like sending a kid away to college,” says Greenhouse, who joined the project in 1997. “It’s an emotional thing because that phase of life is over. Now the kid is a million miles away, and it’s not coming back.”

Scientists expect Webb to operate for 20 years—or more. Greenhouse is excited to see what the telescope will show us. “It’s giving us our first high-definition view of the universe,” he says, “and it’s going to be fantastic.”