James Webb Space Telescope (JWST) research, supported by Hubble Space Telescope (HST) data, is revealing exciting new information about star and planet formation from observations of four nearby galaxies.

In these galaxies, researchers observed thousands of young stars in different clusters at various stages of evolution, according to a recent paper published in Nature Astronomy. The main takeaway from the JWST and HST research is that the more massive a star cluster is, the faster it pushes its natal gas away, allowing it to emerge from its cloud, at the expense of planet formation.

Galactic Evolution

At the heart of galactic evolution are star clusters, clouds of gas from which stars coalesce under gravitational forces. Over time, stars produce radiation, stellar winds, and supernovae that disperse these natal clouds, ending the period of star formation and leaving residual gas to drift through space. Once the gas is cleared, light from the stars can propagate more freely throughout the galaxy in a process known as stellar feedback, pushing away additional gas before it can be used to form new stars.

Astronomers have managed to observe a handful of local star-forming regions within our galaxy and nearby dwarf galaxies, but our vantage point provides only a limited view. Nearby galaxies offer better opportunities to survey star-forming regions and star clusters with the JWST and HST. By combining observations from both within and beyond our galaxy, astronomers can assemble a broader dataset that allows for deeper analyses of star formation.

JWST Peers Out at the Cosmos

Infrared instruments like those aboard the JWST have been essential for understanding star-forming clouds, allowing researchers to peer through their dense gas and dust and glimpse what lies within.

Behind that gas, some of the earliest stages of star cluster development are taking place, offering new insight into the beginnings of galaxies. One of the biggest unresolved questions has been how long it takes for a cloud to disperse, allowing the light from a star cluster to escape into the wider galaxy.

The combined observations from HST and JWST provide the broadest spectral view of young star clusters astronomers have ever obtained. The galaxies at the center of the recent study are Messier 51, Messier 83, NGC 628, and NGC 4449. After an international team of researchers analyzed images captured by the two space telescopes, they concluded that the more massive a star cluster is, the faster it clears away its gas.

9000 Clusters Before the JWST

In these galaxies, researchers identified nearly 9,000 star clusters at various evolutionary stages, ranging from fully obscured by natal gas clouds to completely cleared, with intermediate stages in between. JWST’s infrared capabilities revealed partially or fully obscured clusters, while Hubble’s visible-light instruments showed those that had already cleared their natal clouds. The timescale for dispersing natal gas clouds ranged from about five million years for the most massive clusters to as long as eight million years for less massive ones.

“Simulations of star formation and stellar feedback have struggled to reproduce how star clusters form and emerge from their natal clouds. These results give us important new constraints on that process,” explained lead author Angela Adamo of Stockholm University and the Oskar Klein Center in Sweden.

Researchers already knew that massive star clusters emitted most of a galaxy’s ultraviolet light, but the new findings also demonstrate that they begin dispersing that light earlier than smaller clusters. By tracking how stellar feedback waxes and wanes across different parts of a galaxy, researchers can better understand how it redistributes essential star-forming gas.

Ironically, the faster dispersal of natal clouds in massive clusters may undermine planet formation by exposing protoplanetary disks to ultraviolet radiation earlier, reducing their ability to capture gas needed to form planets. In this way, some of the universe’s most massive star clusters may also impose severe limitations on planet formation, a phenomenon that has also been observed in our own Milky Way.

The paper, “The Emerging Timescale of Young Star Clusters Regulated by Cluster Stellar Mass,” appeared in Nature Astronomy on May 06, 2026.

Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org, and follow him on Twitter @mdntwvlf.

New data collected by NASA’s James Webb Space Telescope (JWST) is helping researchers map the cosmic web in the greatest detail ever achieved, providing new insights into the network of galaxies as improved resolution reveals hidden features.

An international team of researchers led by the University of California, Riverside, revealed their newest findings based on Webb telescope data in a recent study published in the Astrophysical Journal, tracing the cosmic web back to the first billion years of our universe.

The cosmic web consists of filaments and sheets of dark matter that connect the universe’s galaxies through the voids of space, forming an intricate architecture and driving galaxy evolution.

James Webb Space Telescope

JWST has been a tremendous boon to scientists since its 2021 launch, revealing faint, distant galaxies in the infrared spectrum that would previously have been unresolvable. Researchers have used it for everything from collecting more precise data on the Hubble tension to discovering what astronomers call “Little Red Dots,” a series of unexpected, distant, bright red objects.

The speed of light is measured at 5.88 trillion miles per year, which defines the light-year, the unit astronomers use to measure distances across the cosmos. One billion light-years is considered our local neighborhood, but JWST observations stretch far beyond that, due to its incredible clarity. This allows scientists to resolve light from distant corners of the universe, which is now only reaching us billions of years later, providing a window into the ancient universe.

COSMOS-Web

COSMOS-Web, the largest JWST study ever conducted, provided 13.7 billion years of cosmic data for researchers to use in their mapping project. Designed expressly for mapping the cosmic web, COSMOS-web explored an area of sky the size of three full moons.

“JWST has completely changed our view of the universe, and COSMOS-Web was designed from the start to give us the wide, deep view we need to see the cosmic web,” said lead author Hossein Hatamnia, a graduate student at UCR and Carnegie Observatories. “For the first time, we can study the evolution of galaxies in cluster and filamentary structures across cosmic time, all the way from when the universe was a billion years old up to the nearby universe.”

With its incredibly high level of clarity, comparing the new JWST map to earlier Hubble Space Telescope maps of the same region reveals new structures that previous efforts failed to resolve. 

“The jump in depth and resolution is truly significant, and we can now see the cosmic web at a time when the universe was only a few hundred million years old, an era that was essentially out of reach before JWST,” said co-author Bahram Mobasher. “What used to look like a single structure now resolves into many, and details that were smoothed away before are now clearly visible.”

JWST Peers Back in Time 

“The telescope detects many more faint galaxies in the same patch of sky, and the distances to those galaxies are measured far more precisely,” Mobasher added. “Each galaxy can therefore be placed into the correct slice of cosmic time, sharpening the map’s resolution.”

This means that the new map is not only filling in scientific knowledge about the broader structure of the universe, but also how the structure was built over time. In this data, the team discovered that the cosmic web had a major effect on galaxy growth over time, while also suppressing star formation in older galaxies. The detailed maps of the comic web developed under COSMOS-web will be released to the public.

“The pipeline used to build the map, the catalog of 164,000 galaxies and their cosmic density,” Mobasher concluded, “and a video showing the cosmic web evolving across billions of years, has been released to the public.”

The paper, “Large-Scale Structure in COSMOS-Web: Tracing Galaxy Evolution in the Cosmic Web up to z ∼ 7 with the Largest JWST Survey,” appeared in the Astrophysical Journal on May 6, 2026.

Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org, and follow him on Twitter @mdntwvlf.