Less than a century ago, we humans believed that the universe ended at the very end of the Milky Way. At the point where the last starlight of our home galaxy was extinguished, an endless nothingness began.
To Edwin Hubble. The famous astronomer was diligently searching 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 tightly packed bundle of stars in the Milky Way, but a galaxy of its own, 2.5 million light-years away. us. Hubble knew how powerful technological progress was: bigger, better telescopes would help expand our horizons even further.
Eighty years later, the eponymous Hubble Space Telescope would once again change our view of the cosmic horizon with the release of the Hubble Ultra Deep Field Image, a picture of the universe that stretches so far back in space and time that it reveals galaxies barely born 600 million years after the Big Bang.
Today, as of July 11, 2022, our horizon expands once more. A hundred years of advances—in telescopes, astronomy, astrophysics, engineering, rocket science, mathematics, hell, even online video streaming—have led to NASA unveiling the first image ever taken by the James Webb Space Telescope.
After a long wait that led to heated discussion about NASA TV’s “holding music” online, President Joe Biden had the honor of releasing Webb’s first look at the 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 provided a historic first image from all of space.
“If you 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 one little speck,” NASA Administrator Bill Nelson said during the press conference.
The full image is below.
All the mayhem of the highest resolution image of the infrared universe yet.
NASA, ESA, CSA and STScI
Deep Field probes a corner of space known as SMACS 0723 that has been observed by space telescopes such as the Hubble. It contains a huge cluster of galaxies that function like a lens, magnifying the light of galaxies much further out in space.
One of the most notable aspects of this Webb image—and images to come—is the hexagonal light you can see in the image, a function of how the mirrors on the James Webb Telescope are shaped.
There is also a circular blur of light in the center of the image. This is the “lensing” effect. The gravity of the huge foreground clusters, which are only about 4 billion light-years away, changes the way light from deep, deep space reaches the telescope. In some cases, galaxies appear as two points due to the effect, 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 region, the difference is… mind-blowing.
The image itself isn’t exactly “hot out of the telescope”. That’s not what Webb sees. Webb’s imaging capabilities capture infrared light from space objects in black and white, just like Hubble, and image processing software is used to reveal all the intricacies of space. Those who helped create the images then performed a feat of technical and artistic wizardry: they mapped the infrared wavelengths into colors to highlight the most important features in the image.
Some of the galaxies in the image existed only a few hundred million years after the Big Bang. Because of Webb’s powerful optics, we are seeing 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 would expect them to look smaller than the blue ones,” said Jonty 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 make your head hurt, but when these old galaxies first emitted light, the universe was much more compact, meaning they were much closer at the time. Gah!
While Deep Field is enjoyable, it’s only an appetizer. Tomorrow, NASA will provide a buffet of Webb images for you to enjoy forays into 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’ll want to enjoy these as well. We’ve got you covered: Here’s when and where to catch the drop, but you can also watch CNET Highlights live, which we’ve embedded below.
Updated at 6pm PT: Added comments
Add Comment