A New View of Space

On July 12, 2022, the U.S. space agency, NASA, released a series of colorful new images to the public (see Space Snapshots). One showed what looked like a jagged landscape against a glittering sky. Others showed gleaming stars, swirling galaxies, and glowing clouds of dust. Around the world, jaws dropped.

The stunning photos were taken by the James Webb Space Telescope. It’s the largest and most powerful telescope ever sent to space. Engineers and scientists from 14 countries built and tested the telescope over 30 years. It was launched into orbit on December 25, 2021.

Over the next decade, the telescope will take millions of pictures of deep space. It promises to transform our understanding of the universe, says Webb project scientist Klaus Pontoppidan. “It’s a discovery machine.”

The public saw a series of amazing images on July 12, 2022 (see Space Snapshots). The photos came from NASA. That’s the U.S. space agency. One pictured what looked like a jagged landscape. It was set against a sparkly sky. Another showed gleaming stars. Still others showed swirling galaxies and glowing clouds of dust. People around the world were in awe.

The James Webb Space Telescope took the stunning photos. It’s the largest and most powerful telescope ever sent to space. Engineers and scientists from 14 countries worked on the telescope. It took more than 30 years to build and test. It was launched into orbit on December 25, 2021.

The telescope will take millions of pictures of space over the next decade. They could change what we know about the universe, says Klaus Pontoppidan. He’s a Webb project scientist. “It’s a discovery machine,” says Pontoppidan.

Telescopes contain lenses or mirrors that collect and focus light. That creates magnified images of faraway objects. More than 400 years ago, the astronomer Galileo Galilei used a small telescope to make some of the earliest discoveries about space.

Over time, engineers built telescopes that were larger and stronger. In 1990, NASA launched the first major telescope into space. Above Earth’s atmosphere, the Hubble Space Telescope had a clearer view of space than telescopes on Earth. It collected light from stars billions of light-years away.

Telescopes have lenses or mirrors. They collect and focus light. That makes faraway objects look closer. Galileo Galilei was an astronomer. He lived more than 400 years ago. He used a small telescope to make some of the earliest discoveries about space.

Engineers built larger and stronger telescopes over time. NASA launched the first major telescope into space in 1990. It was the Hubble Space Telescope. It orbits high above Earth’s atmosphere. That gives it a clearer view of space than telescopes on Earth. It collects light from stars billions of light-years away.

The Hubble telescope has orbited Earth for three decades, taking 1.5 million pictures of deep space. It has allowed scientists to see ancient stars and galaxies as they appeared billions of years ago. How? Light from the farthest-away stars takes billions of years to reach telescopes like Hubble. By then, the stars have changed. Some may no longer exist! “Telescopes see light as it appeared in the past,” says Pontoppidan.

Hubble expanded humans’ understanding of space. But the telescope was only able to collect visible light, the kind the human eye can see. The Webb telescope is designed to detect a type of light called infrared light. It’s invisible to the human eye. As visible light travels from the oldest and farthest-away stars and galaxies, it shifts into infrared light. By detecting this light, the Webb telescope can show scientists what space looked like 13 billion years ago. That’s when scientists think the universe first formed!

The Hubble telescope has been in orbit for three decades. It’s taken 1.5 million pictures of space. It’s shown scientists ancient stars and galaxies. They look just as they were billions of years ago. How? Light from the farthest stars takes billions of years to reach us. The stars themselves have changed by then. Some may no longer exist! “Telescopes see light as it appeared in the past,” says Pontoppidan. 

Hubble added to what humans know about space. But the telescope collects only visible light. That’s the kind the human eye can see. Visible light travels from the oldest and farthest stars and galaxies. It shifts to infrared light as it travels. Infrared light is invisible to the human eye. The Webb telescope detects this light to show what space looked like 13 billion years ago. That’s when scientists think the universe first formed!

Building the Webb telescope was an enormous engineering challenge. The telescope is three stories tall. Its main mirror is made up of eighteen 1.2-meter (4-foot) hexagonal pieces. The telescope is also equipped with a shield the size of a tennis court. This protects its instruments from the sun’s heat. It was designed to be folded origami-style to fit inside a rocket.

When the Webb telescope launched into space, researchers held their breath. The mission had 344 “single-point failures.” These were places where the entire mission could have been lost if one thing went wrong. At a distance of 1.6 million kilometers (1 million miles) from Earth, the telescope unfolded in a complicated series of steps. First, the telescope’s sunshield opened up. Next, the mirrors fit together like a puzzle.

Step by step, the Webb telescope deployed without a hitch. As the first images came into view, many were surprised by their level of detail. “These distant galaxies were photobombing us,” says Pontoppidan.

Building the Webb telescope was a big challenge. The telescope is three stories tall. Its main mirror is made up of 18 six-sided pieces. Each one is 1.2 meters (4 feet) wide. The telescope also has a shield the size of a tennis court. This protects it from the sun’s heat. The shield was made to fold like origami to fit inside a rocket.

Scientists held their breath when the Webb telescope launched. There were 344 places where things could go wrong. Just one could end the entire mission. The telescope flew 1.6 million kilometers (1 million miles) from Earth. Then it unfolded. It was a complicated series of steps. First, the telescope’s sunshield opened. Then the mirrors fit together like a puzzle.

The Webb telescope deployed without a hitch. The first images came into view. Many people were surprised by what they could see. “These distant galaxies were photobombing us,” says Pontoppidan.

Since its launch, the Webb telescope has captured some groundbreaking images. In one, scientists identified a red light as the oldest known galaxy. Scientists believe this galaxy formed 300 million years after the universe was born.

The Webb telescope will remain in space for 10 years or longer. As it orbits the sun, it will capture images of exploded stars, ancient galaxies, and more. Scientists hope it will help answer questions about how the universe formed. The telescope will also search for exoplanets orbiting distant stars. Some of these places could support life.

“We’re on our own little planet in our own galaxy,” says Webb project scientist Randy Kimble. But with Webb, “we’re able to gain a greater understanding of how everything in space works. It’s very exciting.”

The Webb telescope has already captured some incredible images. In one, scientists spotted the oldest known galaxy. Scientists believe it formed 300 million years after the universe was born.

The Webb telescope will remain in space for 10 years or longer. It will continue to orbit the sun in step with Earth. It will capture images of exploded stars, ancient galaxies, and more. Scientists hope it will help answer questions about how the universe formed. The telescope will also look for exoplanets. They orbit distant stars. Some of these places could support life.

“We’re on our own little planet in our own galaxy,” says Randy Kimble, a Webb project scientist. But with Webb, he says, “we’re able to gain a greater understanding of how everything in space works. It’s very exciting.”