This new release presents the largest interactive deep space catalog ever created - over 800,000 galaxy images - offering scientists and the public unparalleled and interactive access to the early universe.
ROCHESTER, N.Y., June 5, 2025 /PRNewswire-PRWeb/ -- COSMOS-Web provides the largest view deep into the universe ever, and now all of its data are available publicly in an easily searchable format.
COSMOS-Web was the largest General Observer program selected for Cycle 1 of the James Webb Space Telescope (JWST). The survey mapped 0.54 square degrees of the sky (about the area of three full moons) with the Near Infrared Camera (NIRCam) and a 0.2 square degree area with the Mid Infrared Instrument (MIRI). While previous surveys have aimed to help astronomers map and understand what exists in the vast universe, the advanced instruments of JWST have allowed COSMOS-Web to study galaxy evolution through a long range of history unlike ever before.
The survey has captured some of the rarest objects in the universe, and now these images and supporting data are available for scientists to delve in and make further discoveries.
"The sensitivity of JWST lets us see much fainter and more distant galaxies than ever before, so we're able to find galaxies in the very early universe and study their properties in detail," said Jeyhan Kartaltepe, associate professor at Rochester Institute of Technology and lead researcher of COSMOS-Web. "The quality of the data still blows us away. It is so much better than expected."
COSMOS2025, the catalog containing the photometry, morphology, redshifts, and physical parameters of galaxies from COSMOS-Web, delivers a combination of sensitivity, spatial resolution, and field-of-view to observe nearly 800,000 galaxies. Using JWST imaging, ground-based telescope data, and previous COSMOS data, the catalog makes an unprecedented amount of information freely available, opening many unexplored scientific avenues.
"This was an ambitious undertaking that required the development of innovative technologies to simultaneously measure the photometry and morphology of nearly 800,000 galaxies across 37 images," said Marko Shuntov, postdoctoral researcher at Cosmic DAWN Center. "Building the catalog required tremendous teamwork, and it was all worth it because ultimately it has delivered some of the highest quality redshifts and physical parameters of galaxies that will enable groundbreaking science."
The raw data retrieved during COSMOS-Web was so vast that it was difficult and incredibly time-consuming for scientists to work through it. The public availability of the catalog takes that work out of the equation for the community. The COSMOS-Web team worked diligently to reduce the data, eliminating artifacts, subtracting backgrounds, and improving the astrometry in order to provide accurate photometric and morphological analyses.
The breakthroughs already discovered through JWST's observations have shown how essential NIRCam data is for understanding galaxies in the early universe. Ensuring that the data are science-ready is an achievement that makes COSMOS-Web the standard calibration for future, large surveys.
"We combined more than 10,000 images of the sky together to form the largest contiguous image available from JWST," explained Maximilien Franco, postdoctoral researcher at Université Paris-Saclay. "To do this, we needed to ensure that all the images were properly aligned with existing data, and also to correct for any observational biases. It was incredible to reveal galaxies that were previously invisible, and very gratifying to finally see them appear on our computers."
Likewise, MIRI plays a critical role in determining the mass of early galaxies and investigating star formation over cosmic time. It has already been instrumental in confirming some of the most distant galaxies discovered by JWST. Using longer wavelengths that are less affected by dust extinction, MIRI has the ability to detect and characterize galaxies at higher redshifts, or at earlier times in the universe.
"It's remarkable to see how much progress we've made since Spitzer's pioneering work in the mid-infrared," said Santosh Harish, postdoctoral research associate at Rochester Institute of Technology. "With MIRI, we're now accessing an unprecedented level of detail in this wavelength range, providing new insights into the processes driving galaxy evolution and the growth of black holes. The leap in sensitivity and spatial resolution is extraordinary, and MIRI observations from COSMOS-Web are a fine example of what this instrument is capable of."
Along with the data itself and three initial papers on the catalog, near infrared imaging, and mid infrared imaging, the data release also includes an interactive viewer where users can directly search images for specific objects or click on objects to see their properties.
In addition, two new COSMOS-Web studies—one examining the structural evolution of brightest group galaxies over the past 11 billion years, and another applying artificial intelligence to estimate key galaxy properties from photometry—highlight the wide scientific potential of the catalog.
"Thanks to JWST and the COSMOS-Web survey, we can now trace how galaxies shut down star formation, undergo morphological transformation, and how these processes are shaped by their environment across cosmic time, even predicting galaxy properties using AI-driven methods," said Ghassem Gozaliasl, astrophysicist and researcher at Aalto University.
When the JWST launched in 2021, the COSMOS-Web team of nearly 50 researchers around the world had the longest observing time during the telescope's first year. The team set out with three primary goals: to map and build understanding of the Reionization Era (in the universe's first billion years); to trace and identify massive galaxy evolution in the first two billion years; and to study how dark matter is linked to visible matter within galaxies.
After more than 150 visits and 250 hours of observations, the JWST data from COSMOS-Web has provided the information to obtain those goals. The survey has sent scientists into a new age of space observation and data analysis, and has opened the door to a future of understanding and discovery like never before.
"We have data and catalogs that we're very sure of, that we've tested and put a lot of work into," said Kartaltepe. "I can't overstate how much the field has changed. With data from JWST, we now have a new window on the universe."
COSMOS-Web is jointly led by Kartaltepe and Caitlin Casey, professor of physics at University of California, Santa Barbara, and is part of The Cosmic Evolution Survey (COSMOS). Beginning in 2007, COSMOS joined together more than 200 scientists across the globe to study the formation and evolution of galaxies using both space-based and ground-based telescopes. The remarkable longevity of the collaboration is a testament to the importance of open, accessible science.
For more information on COSMOS-Web, go to the program's website. The COSMOS-Web images, catalog, and interactive viewer are available through the team's data release website.
Video available: https://drive.google.com/file/d/1Eo9WcVkS6B35lHviz3a01dQ7cFx7DmzX/view?usp=sharing
Media Contact
Mollie Radzinski, Rochester Institute of Technology, 585-520-1487, [email protected], www.rit.edu
SOURCE Rochester Institute of Technology
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