Until Edwin Hubble. The famous astronomer diligently searched the sky for twinkling stars from the Mount Wilson Observatory in California. His work with the Hooker telescope effectively doubled the size of the universe in 1923, when he and others helped reveal that Andromeda was not a cluster of stars within our Milky Way, but the galaxy’s own, 2.5 million light-years away . Hubble knew how powerful technological advances were: Bigger, better telescopes would help expand our horizons even further.
Eighty years later, the eponymous Hubble Space Telescope would change our view of the cosmic horizon once again with the release of the Hubble Ultra Deep Field Image, a photograph of the universe that stretches so far back in space and time that it revealed galaxies that born just 600 million years after the Big Bang.
Today, as of July 11, 2022, our horizon is expanding once again. A hundred years of advances – in telescopes, astronomy, astrophysics, engineering, rocket science, mathematics, hell, even online video streaming – have led NASA to unveil the first image taken by the James Webb Space Telescope.
After a long wait that led to a heated debate over NASA TV’s “hold music” online, it was President Joe Biden who had the honor of releasing Webb’s first glimpse of the entire universe, an image dubbed “Webb’s First Deep Field” on Monday. The press conference lasted only 10 minutes and was a huge missed opportunity, but it gave a historic first look from around the world.
“If you were to hold a grain of sand on the tip of your finger at arm’s length, that’s the part of the universe you see — just a tiny bit,” NASA Administrator Bill Nelson said during the news conference.
The full image is below.
The whole shebang in the highest resolution image of the infrared universe to date.
NASA, ESA, CSA and STScI
The Deep Field examines a corner of space known as SMACS 0723, which has been observed by space telescopes such as Hubble. It contains a mammoth cluster of galaxies that acts as a lens, magnifying the light of galaxies from much further out in the universe.
One of the most remarkable aspects of this Webb image—and the images that will follow—is the six-ray light you can see in the image, a function of how the mirrors on the James Webb Telescope are configured.
There is also a circular smudge of light across the center of the image. This is the “lensing” effect. The gravity of the massive foreground clusters, only about 4 billion light-years away, changes the way light from deep, deep space reaches the telescope. In some cases, galaxies appear in two spots due to the phenomenon, and astronomers can study this light to better understand what these deep galaxies look like.
When you compare it to the Hubble image of the same area, the difference is… staggering.
The image itself isn’t exactly “hot from the telescope”. That’s not what Webb sees. Webb’s imaging capabilities capture infrared light from cosmic objects in black and white, similar to Hubble, and image processing software is used to reveal all the subtle nuances of space. Those who helped create the images then perform a feat of technical and artistic wizardry: They map infrared wavelengths to colors to highlight an image’s most important features.
Some of the galaxies in the image only existed a few hundred million years after the Big Bang. Because of Webb’s strong visuals, we see them for the first time. What’s really interesting about them is that they appear larger than galaxies that are technically much closer.
“The redder galaxies in the image are much further away from us than the bluer ones – so you’d expect them to look smaller than the blue ones,” says Jonti Horner, an astrophysicist at the University of Southern Queensland in Australia. Instead, he notes, redder galaxies appear much larger due to a quirk of light known as “angular diameter rotation.” It will give you a headache, but when these old galaxies first emitted light, the universe was much more compact, meaning it was much closer at the time. Gah!
While Deep Field is enjoyable, it’s just the entrance. Tomorrow, NASA will provide a buffet of Webb images for you to enjoy a groundbreaking look at deep space. The release will highlight dazzling nebulae, illuminate alien worlds and pull back the curtain on a cluster of colliding galaxies. If this first image is anything to go by, you’re going to want to enjoy yourself too. We’ve got you covered: See when and where you can catch the drop, but you can also watch the CNET Highlights live stream, which we’ve embedded below.
Updated 6 p.m. PT: Added comments
