The universe was born in darkness 13.8 billion years ago, and even after the first stars and galaxies exploded a few hundred million years later, they too remained dark. Their brilliant light, stretched by time and the expanding cosmos, dimmed in the infrared, rendering them—and other clues to our beginnings—inaccessible to any eye and instrument.
So far. On Tuesday, the James Webb Space Telescope, the most powerful space observatory ever built, offered a spectacular slideshow of our previously unseen nascent cosmos. Ancient galaxies covering the sky like jewels on black velvet. Newborn stars shining deep in cumulus clouds of interstellar dust. Hints of water vapor in the atmosphere of a distant exoplanet.
Their sum is both a new vision of the universe and a view of the universe as it once appeared new.
“It’s always been there,” said Jane Rigby, an astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Md., and the telescope’s operations manager. “We just had to build a telescope to see what was out there.”
The Webb Telescope—NASA’s vaunted successor to the Hubble Space Telescope, 30 years and nearly $10 billion in the making—is equipped to access this realm of cosmic history, studying the first stars and galaxies and searching for closer, potentially habitable worlds. It is a collaboration between NASA, the European Space Agency and the Canadian Space Agency.
“We’re looking for the first things to come out of the Big Bang,” said John Mather, senior project scientist for the telescope.
President Biden offered a preview Monday afternoon when he unveiled what NASA officials and astronomers hailed as the deepest image ever taken of space, a mark likely to be passed before the end of the week as NASA’s computers exit more data.
The image of a distant star cluster called SMACS 0723 revealed the presence of even more distant galaxies scattered across the sky. The light from these galaxies, magnified into view by the cluster’s gravitational field, originated more than 13 billion years ago.
To look out into space is to peer into the past. Light travels at a constant speed of 186,000 miles per second, or nearly six trillion miles per year, through the vacuum of space. To observe a star 10 light years away is to see it as it existed 10 years ago, when the light left its surface. The further away a star or galaxy is, the older it is, making any telescope something of a time machine.
Astronomers theorize that the most distant, earliest stars may not look like the stars we see today. The first stars were composed of pure hydrogen and helium left over from the Big Bang, and could have grown much more massive than the sun—and then collapsed fast and furiously into supermassive black holes of the kind that now populate the centers of most galaxies.
The new photos were released during an hour-long ceremony at the Goddard Space Flight Center hosted by Michelle Thaler, associate director of the science communication center, with video stops around the world. A few miles away at the Space Telescope Science Institute in Baltimore, an overflow crowd of astronomers whooped and hollered and oohed and aahed as new images flashed on the screen — proof that their telescope was working even better than expected.
An infrared skyscape shows the Stefan Quintet, five galaxies packed incredibly close together in the constellation Pegasus. Four are so closely engaged in a gravitational dance that they will eventually merge. Indeed, the image reveals a streak of dust that heats up as two of the galaxies rip stars away from each other.
Learn more about the James Webb Space Telescope
After traveling nearly a million miles to reach a location beyond the Moon, the James Webb Space Telescope will spend years observing the cosmos.
A view of the Southern Ring Nebula, the remains of an exploded star, has revealed hints of complex carbon molecules known as polycyclic aromatic hydrocarbons, or PAHs, floating in its environment. Such molecules drift through space, settling in clouds that then give birth to new stars, planets, asteroids—and whatever life may subsequently sprout.
“It’s possible that the formation of PAHs in these stars was a very important part of how life began,” said Bruce Balik, professor emeritus of astronomy at the University of Washington. “I’m overwhelmed.”
The most impressive image was of the Carina Nebula, a vast, swirling cloud of dust that is both a stellar nursery and home to some of the brightest and most explosive stars in the Milky Way. Viewed in infrared, the nebula looked like an overhanging, eroded coastal cliff, studded with hundreds of stars the likes of which astronomers had never seen before.
“It took me a while to figure out what to call this image,” said Amber Strawn, deputy project scientist for the telescope, pointing to a rocky structure.
Dr Strawn added that he couldn’t help but think about the scale of a nebula full of stars with planets of their own.
“We humans are really connected to the universe,” she said. “We are made of the same stuff in this landscape.”
There was equal relief and praise from astronomers and viewing parties around the world.
“This event blew my mind,” said Alan Dressler, an astronomer at the Carnegie Observatory who was instrumental in planning the telescope 30 years ago. “I guess I’m not as exhausted as I thought.”
He added: “The growth in our understanding of the universe will be as great as it was with Hubble, and that’s really saying something.” We have a great adventure ahead of us.”
“Food Madness” in the sky
The photos and other data released Tuesday were selected by a small team of imaging experts and public relations specialists for the images’ ability to show the range and power of the new telescope — and to wow the public.
They will be followed in the next six months by the results of studies in NASA’s early launch science programs. Some results, including images of galaxies even more distant than the one Mr Biden showed on Monday, will be available later this week. On Thursday, all the data collected during testing of the telescope and its instruments will become available.
Now that the images are out, “there is going to be an astronomer feeding frenzy!” Garth Illingworth, a researcher at UC Santa Cruz and the initiator of the telescope program four decades ago, wrote in an email.
Early launch science programs designed to kickstart the Webb era include studies of the solar system, galaxies, intergalactic space, massive black holes and stellar evolution.
Jupiter and its myriad intriguing moons, such as Europa, the target of an upcoming NASA mission, will be one focus. Two other studies will focus on exoplanets, including the Trappist-1 system, just 40 light-years away, where seven planets orbit a faint red dwarf star. Three of these planets are Earth-sized rocks orbiting in the habitable zone, where water may be present on the surface.
I dream of the invisible light
Just as the Hubble Space Telescope has defined astronomy for the past three decades, NASA expects the Web to define the field for a new generation of explorers looking forward to their own encounter with space.
It was a long wait. What started as a next-generation space telescope has evolved into an infrared telescope capable of sensing the heat from the universe’s earliest stars and galaxies.
As space expands, these earliest stars and galaxies are hurtling away from Earth so fast that their light shifts to longer, redder wavelengths, much like the sound of an ambulance siren shifts to lower register as he passes her by. The light from the most distant and earliest galaxies and stars, once blue, is now infrared “heat” radiation invisible to the eye. The same is true of radiation from carbon, ozone, and other molecules of great interest to astrobiologists.
An early planning committee concluded that the telescope should be at least four meters in diameter (Hubble’s was only 2.4 meters wide) and highly sensitive to infrared radiation, and would cost $1 billion. NASA Administrator Dan Goldin liked the idea, but worried that a four-meter telescope would be too small to see the first stars, so he increased the size to eight meters.
However, doubled in size, the telescope will no longer fit aboard an existing rocket. This meant that the telescope’s mirror would have to be collapsible and would have to be unfolded in space. NASA eventually settled on a 20-foot-wide mirror with seven times the light-gathering power of Hubble’s.
Additionally, the telescope must be cooled to minus 380 degrees Fahrenheit to prevent the telescope’s own heat from absorbing faint emissions from distant stars. (One instrument had to be even colder, minus 447 degrees Fahrenheit, just a few degrees above absolute zero.) This was accomplished by parking the telescope permanently behind a canopy.
But all the challenges in developing and building the tool remain. In 1990, NASA sent Hubble into orbit with a deformed mirror; still stinging from that embarrassment, the agency developed a lengthy and expensive program to test the new telescope. The cost rose to $8 billion, and in 2011, Congress nearly canceled the project.
“Webb became the perfect storm,” Dr. Dressler recalls. “The more expensive it got, the more important it was that it didn’t fail, and that made it even more expensive.”
During an early test, the sun shield was torn. “When you’re running a $10 billion telescope, there are no small problems,” said Thomas Zurbuchen, NASA’s associate administrator for science missions. “It’s hard to tell what’s bold and what’s not.”
Christmas for astronomers
The Webb Telescope represents the combined efforts…
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