Side-by-side images from the James Webb and Hubble space telescopes show why NASA spent 25 years and $10 billion on the Webb
- NASA's James Webb Space Telescope is by far the most powerful observatory ever launched into space.
- Even Webb's very first images show why NASA spent 25 years and $10 billion.
- The Hubble Space Telescope captured the same sights, but JWST revealed details that were invisible.
NASA's James Webb Space Telescope floored astronomers and spectators across the globe when it released its first full-color images.
Even the scientists who worked on the telescope were taken aback when they saw those first snapshots in the summer of 2022, telling reporters that they sobbed, fell speechless, or dropped their jaws so far that they "nearly broke."
The telescope — called Webb or JWST for short — has continued to wow the world with new discoveries and mesmerizing portraits of the universe.
It has investigated distant planets that could be habitable, spotted the oldest black hole ever, and peered into the universe's ancient dark ages, giving astronomers answers in some cases and raising new mysteries in others.
JWST has snagged so many feats that it's easy to forget what a scientific marvel each image is. To grasp how far Webb has taken us, we can revisit its first images.
Even those preliminary snapshots revealed countless stars, galaxies, and fine details that hadn't been seen before. They painted the births and deaths of stars in sharp, new colors and peered further into the distance than any infrared telescope ever had.
Before Webb, images like these only came from the Hubble Space Telescope, which rocketed into Earth's orbit in 1990. But the JWST pictures reveal the rewards of the 25 years and $10 billion NASA spent on the observatory — all in a new, wide-ranging spectrum of infrared light.
"We're making discoveries, and we really haven't even started trying yet," Eric Smith, the chief scientist of NASA's astrophysics division, said in a 2022 briefing where the Webb team revealed its first images.
Indeed, these pictures were only warm-ups for the years of science ahead. Here's what they revealed.
JWST clearly showed two stars at the center of this nebula, where Hubble only saw one
The Southern Ring Nebula is a dying star that has imploded and is slowly expelling the layers of its atmosphere in successive waves, creating ever-expanding bubbles of colorful gas. Scientists knew there were two stars at its center, but couldn't see them in images.
The new JWST picture showed the dying star, which glows red because it's surrounded by dust, right next to its white companion star.
With other wavelengths of infrared light, JWST saw different details in the same nebula
This image, captured in near-infrared wavelengths of light, shows the structure of the nebula. The blue bubble at the center is hot, ionized gas that the leftover core of the star has superheated. In the foamy orange outer regions made of newly formed hydrogen, rays of the starlight beam through holes in the inner bubble.
A cluster of five galaxies was much sharper through JWST's lens
Four of the galaxies in this image are about 300,000 light-years away, locked in a cosmic dance as each galaxy's gravity influences the others.
In the JWST image, you can see galaxies in the background that were invisible to Hubble
Webb is 100 times stronger than Hubble, capturing far more galaxies than its predecessor could.
The JWST image also revealed the stellar nurseries created as galaxies merge
"We now see gas and dust, which is being heated up in the collision between those galaxies," Mark McCaughrean, the senior advisor for science and exploration at the European Space Agency — which is collaborating with NASA on the telescope — said when the images were released in 2022.
As gas and dust get compressed and heated, they collapse into new stars. That means the cloud between galaxies in the JWST image is a nursery for the birth of new stars.
"We're actually seeing the process of creation of new stars in this region," McCaughrean said.
This is Hubble's image of a star nursery in the Carina Nebula
And this is JWST's image of the same region
"When I see an image like this, I can't help but think about scale," Amber Straughn, a NASA astrophysicist on the JWST team, said in 2022. "Every dot of light we see here is an individual star, not unlike our sun, and many of these likely also have planets. And it just reminds me that our sun and our planet, and ultimately us, were formed out of the same kind of stuff that we see here."
The JWST image revealed hundreds of stars that weren't visible before
"This is going to be revolutionary," Jane Rigby, a NASA scientist overseeing JWST operations, said in the briefing. "These are incredible capabilities that we've never had before."
Indeed, Webb has been revolutionary in the two years since. There are still more discoveries to come.
This story was originally published on July 12, 2022, and most recently updated on September 23, 2024.