Hubble Captures 'Sneak Peek' of James Webb Space Telescope Discoveries

Monisha Ravisetti Former Science Writer
Monisha Ravisetti was a science writer at CNET. She covered climate change, space rockets, mathematical puzzles, dinosaur bones, black holes, supernovas, and sometimes, the drama of philosophical thought experiments. Previously, she was a science reporter with a startup publication called The Academic Times, and before that, was an immunology researcher at Weill Cornell Medical Center in New York. She graduated from New York University in 2018 with a B.A. in philosophy, physics and chemistry. When she's not at her desk, she's trying (and failing) to raise her online chess rating. Her favorite movies are Dunkirk and Marcel the Shell with Shoes On.
Monisha Ravisetti
3 min read
A section of the new image, showing stars and galaxies against a dark sky.

A patch of sky imaged by 3D-DASH, showing the brightest and rarest objects of the universe like monster galaxies.

Gabe Brammer

What's happening

The Hubble Space Telescope just captured the largest-ever near-infrared image of the sky.

Why it matters

This giant survey could pave the way for next-gen James Webb Space Telescope discoveries, and eventually, help humans understand some of the most elusive regions of our universe.

Amid the thrill of discussing astronomy's shiny new toy, the James Webb Space Telescope, we can't forget about Hubble.

Since its launch in late December of last year, JWST has been making waves, carrying the hopes and dreams of wide-eyed scientists, along with gold-plated mirrors and an array of high-tech infrared cameras that can pierce stardust and help us solve long-standing black hole mysteries. But tried and true Hubble is still toiling away, and in fact, just hit a pretty big milestone. 

The Hubble Space Telescope, which ventured out into the cosmos way back in 1990, has captured its largest-ever near-infrared image of space and thus is even treading into waters that JWST is poised to explore. 

This remarkable image could cast a spotlight on some of the rarest objects in the universe, such as monster galaxies that are the product of massive galaxy mergers or super violent black holes lurking deep in interstellar space.

"It was difficult to study these extremely rare events using existing images, which is what motivated the design of this large survey," Lamiya Mowla said in a statement. Mowla is an astrophysicist at the University of Toronto and lead author of a study on the survey, of which a preprint is available on arXiv. It's soon to be published in The Astrophysical Journal.

Part of a new high-resolution survey dubbed 3D-Dash, which stands for "drift and shift," Hubble's latest dataset spans an area of the sky almost six times the size of the moon as seen from Earth. You can actually explore it for yourself here. What you're looking at is a mosaic of multiple shots taken by Hubble that were later stitched together.

Try zooming out and dragging the screen around -- it's quite spectacular how much ground (sky?) this image covers.

Photo mosaic showing a variety of galaxies

Galaxies from the last 10 billion years witnessed in the 3D-Dash program.

Lamiya Mowla

"Since its launch more than 30 years ago, the Hubble Space Telescope has led a renaissance in the study of how galaxies have changed in the last 10 billion years of the universe," Mowla said. "The 3D-DASH program extends Hubble's legacy in wide-area imaging, so we can begin to unravel the mysteries of the galaxies beyond our own."

What is an infrared image?

When you look up at the sky, even if you're situated in the darkest forest glen on Earth, you aren't seeing all the stars. And it's not because some of the stars aren't in your field of view. 

They're there -- but they're invisible.

Human eyes can only visualize light wavelengths within a certain region of the electromagnetic spectrum. Just beyond this region lies infrared light. And galaxies and stars that are really, really far away give off exactly this type of light -- so they're essentially hidden to our eyes, no matter what we try to do. 

But Hubble, and JWST too, have a way around our human restriction. Scientists embedded both these instruments with what are basically infrared light detectors. 

A diagram of the electromagnetic spectrum, showing what regions Hubble and Webb can see.

This infographic illustrates the spectrum of electromagnetic energy, highlighting the portions detected by NASA's Hubble, Spitzer and Webb space telescopes.

NASA and J. Olmsted [STScI]

As evident from the diagram, JWST's infrared powers are much (much) stronger -- which is why it holds potential to show us tons of things our eyes can't see -- but Hubble does have some of these special light processing capabilities.

Plus, Hubble actually has a leg up on JWST here. 

Per the researchers behind the new study, JWST is designed to take highly sensitive, close-up images of deep space so we get very clear pictures of small interstellar areas. That's incredibly exciting since we'll probably get pictures of faraway stars, galaxies and other cosmic phenomena with a level of clarity similar to what we get for images of space-borne objects closer to Earth.

But Hubble can take extremely wide-field images like the new one we're looking at. Eventually, such expansive datasets could inform future JWST studies, helping the next-gen scope point in the right direction for revealing observations.

As Ivelina Momcheva, data scientist at the Max Planck Institute for Astronomy and principal investigator of the study, puts it, "It gives us a sneak peek of future scientific discoveries and allows us to develop new techniques to analyze these large datasets."