Face-on spiral galaxy, NGC 628, is split diagonally in this image: The James Webb Space Telescope’s observations appear at top left, and the Hubble Space Telescope’s on bottom right. Webb and Hubble’s images show a striking contrast, an inverse of darkness and light. Why? Webb’s observations combine near- and mid-infrared light and Hubble’s showcase visible light. Dust absorbs ultraviolet and visible light, and then re-emits it in the infrared. In Webb's images, we see dust glowing in infrared light. In Hubble’s images, dark regions are where starlight is absorbed by dust. (credit: NASA, ESA, CSA, STScI, Janice Lee (STScI), Thomas Williams (Oxford), and the PHANGS team)
NASA’s James Webb Space Telescope has once again pushed the boundaries of space exploration with the release of highly detailed images of nearby spiral galaxies. Captured in both near- and mid-infrared light, these 19 images provide an unparalleled look at the complex structures of galaxies, revealing details that have left astronomers around the world in awe.
The James Webb Space Telescope observed 19 nearby face-on spiral galaxies in near- and mid-infrared light as part of its contributions to the Physics at High Angular resolution in Nearby GalaxieS (PHANGS) program. PHANGS also includes images and data from NASA’s Hubble Space Telescope, the Very Large Telescope’s Multi-Unit Spectroscopic Explorer, and the Atacama Large Millimeter/submillimeter Array, which included observations taken in ultraviolet, visible, and radio light. (credit: NASA, ESA, CSA, STScI, Janice Lee (STScI), Thomas Williams (Oxford), PHANGS Team, Elizabeth Wheatley (STScI)
The images are part of the Physics at High Angular resolution in Nearby GalaxieS (PHANGS) program, a collaborative effort involving over 150 astronomers globally. The PHANGS project, already rich in data from other observatories like the Hubble Space Telescope and the Atacama Large Millimeter/submillimeter Array, has been significantly enhanced by Webb’s contributions. These new images add to our understanding by showcasing the galaxies in infrared light, which is invisible to the human eye.
“Webb’s new images are extraordinary,” says Janice Lee, a project scientist for strategic initiatives at the Space Telescope Science Institute in Baltimore, in a media release. “They’re mind-blowing even for researchers who have studied these same galaxies for decades. Bubbles and filaments are resolved down to the smallest scales ever observed, and tell a story about the star formation cycle.”
Face-on spiral galaxy, NGC 628, is split diagonally in this image: The James Webb Space Telescope’s observations appear at top left, and the Hubble Space Telescope’s on bottom right. Webb and Hubble’s images show a striking contrast, an inverse of darkness and light. Why? Webb’s observations combine near- and mid-infrared light and Hubble’s showcase visible light. Dust absorbs ultraviolet and visible light, and then re-emits it in the infrared. In Webb’s images, we see dust glowing in infrared light. In Hubble’s images, dark regions are where starlight is absorbed by dust. (credit: NASA, ESA, CSA, STScI, Janice Lee (STScI), Thomas Williams (Oxford), and the PHANGS team)
Hubble’s image of NGC 628 shows a densely populated face-on spiral galaxy anchored by its central region, which has a light yellow haze that takes up about a quarter of the view. The core is brightest at the center, washing out light from other objects. Delicate spiral arms start near the center and extend to the edges, rotating counterclockwise. There is more brown dust beginning at the center, but as the arms extend outward, brown dust lanes alternate with diffuse lines of bright blue stars. Throughout the spiral arms, there are bright pink patches of star-forming clusters. (credit: NASA, STScI)
Spiral galaxy NGC 628 is 32 million light-years away in the constellation Pisces. Webb’s image of NGC 628 shows a densely populated face-on spiral galaxy anchored by its central region, which has a light blue haze that takes up about a quarter of the view. In this circular core is the brightest blue area. Within the core are populations of older stars, represented by many pinpoints of blue light. Spiny spiral arms made of stars, gas, and dust also start at the center, largely starting in the wider area of the blue haze. The spiral arms extend to the edges, rotating counterclockwise. The spiraling filamentary structure looks somewhat like a cross section of a nautilus shell. The arms of the galaxy are largely orange, ranging from dark to bright orange. Scattered across the packed scene are some additional bright blue pinpoints of light, which are stars spread throughout the galaxy. In areas where there is less orange, it is darker, and some dark regions look more circular. A prominent dark “bubble” appears to the top left of the blue core. And a wider, elliptical “bubble” to the bottom right. (credit: NASA, ESA, CSA, STScI, Janice Lee (STScI), Thomas Williams (Oxford), and the PHANGS team)
Thomas Williams, a postdoctoral researcher at the University of Oxford, shared the team’s reaction to the influx of data from Webb.
“I feel like our team lives in a constant state of being overwhelmed – in a positive way – by the amount of detail in these images,” notes Williams.
Spiral galaxy NGC 1300 is 69 million light-years away in the constellation Eridanus. (credit: NASA, ESA, CSA, STScI, Janice Lee (STScI), Thomas Williams (Oxford), and the PHANGS team)
Spiral galaxy NGC 1087 is 80 million light-years away in the constellation Cetus. (credit: NASA, ESA, CSA, STScI, Janice Lee (STScI), Thomas Williams (Oxford), and the PHANGS team)
The Webb Telescope’s Near-Infrared Camera (NIRCam) has captured millions of stars, presenting them in stunning blue tones. These images detail both the widespread distribution of stars along the spiral arms and the densely packed star clusters. The Mid-Infrared Instrument (MIRI) data sheds light on the glowing dust and gas in these galaxies, pinpointing areas of active star formation and the early stages of star life.
Astronomers have also been fascinated by the large spherical shells seen in the images, likely the result of stellar explosions that have carved out vast cavities in the interstellar medium.
“These holes may have been created by one or more stars that exploded, carving out giant holes in the interstellar material,” explains Adam Leroy, a professor of astronomy at The Ohio State University in Columbus.
Spiral galaxy NGC 1566 is 60 million light-years away in the constellation Dorado. (credit: NASA, ESA, CSA, STScI, Janice Lee (STScI), Thomas Williams (Oxford), and the PHANGS team)
The images also highlight the red and orange hues of extended gas regions, tracing the spiral arms and revealing patterns that inform scientists about the distribution of gas and dust within galaxies.
These structures tend to follow the same pattern in certain parts of the galaxies,” says Erik Rosolowsky, a professor of physics at the University of Alberta. “We think of these like waves, and their spacing tells us a lot about how a galaxy distributes its gas and dust.”
Spiral galaxy NGC 2835 is 35 million light-years away in the constellation Hydra. (credit: NASA, ESA, CSA, STScI, Janice Lee (STScI), Thomas Williams (Oxford), and the PHANGS team)
At the heart of some galaxies, pink-and-red diffraction spikes indicate the presence of supermassive black holes or extremely bright star clusters.
“That’s a clear sign that there may be an active supermassive black hole,” says Eva Schinnerer, a staff scientist at the Max Planck Institute for Astronomy in Heidelberg, Germany. “Or, the star clusters toward the center are so bright that they have saturated that area of the image.”
The release of these images is just the beginning of a wealth of research opportunities. The PHANGS team has also published the largest catalog of star clusters to date, comprising roughly 100,000 entries. This extensive dataset opens the door for the broader scientific community to engage in analyzing these celestial phenomena.
Spiral galaxy NGC 1512 is 30 million light-years away in the constellation Horologium. (credit: NASA, ESA, CSA, STScI, Janice Lee (STScI), Thomas Williams (Oxford), and the PHANGS team)
Spiral galaxy NGC 1385 is 30 million light-years away in the constellation Fornax. (credit: NASA, ESA, CSA, STScI, Janice Lee (STScI), Thomas Williams (Oxford), and the PHANGS team)
The James Webb Space Telescope continues to fulfill its mission as the world’s premier space science observatory, exploring the mysteries of our solar system, examining distant worlds, and probing the depths of the universe. As an international endeavor led by NASA, with partners including the European Space Agency and the Canadian Space Agency, Webb is not only expanding our knowledge of the cosmos but also our understanding of humanity’s place within it.
