The James Webb Space Telescope's Mid-Infrared Imager (MIRI) shows the Sagittarius B2 region (Sgr B2) in mid-infrared light. (Image credit: NASA, ESA, CSA, STScI, Adam Ginzburg, Nazar Budaev, Tehwa Yu; Image processing: Alyssa Pagan (STScI))
What is it: Sagittarius B2 (Sgr B2) molecular cloud.
Location: 25,000 light years from Earth in the constellation Sagittarius.
When published: September 24, 2025
What makes it special: Stars in the Milky Way galaxy are born in enormous molecular clouds. The most massive of these is Sagittarius B2, which is located just a few hundred light-years from our galaxy's central black hole (Sagittarius A*). This black hole is much richer than it might first appear: it contains 10% of the galactic center's gas, yet it is responsible for approximately half of the current star formation in this region. Why star formation in the galactic center is so uneven remains a mystery to scientists.
You may like
-
The James Webb and Hubble telescopes join forces to explore the cosmic hotbed: Space Photo of the Week
-
Fly among 44 million stars in the latest 3D map of our galaxy from the Gaia telescope – Space Photo of the Week
-
The James Webb Space Telescope has discovered stunning galaxies in the Bullet Cluster: Space Photo of the Week
A full-size image of the star-forming cloud in Sagittarius B2, taken by the JWST telescope.
The MIRI image is completely different: it shows the region's dust clouds illuminated by stars. It reveals pink and purple clouds surrounded by very dark regions dotted with stars. JWST can't see everything: even its infrared vision can't penetrate the densest clouds, which remain dark and opaque in the MIRI image. These hidden regions contain the raw materials for star formation.
Webb's Mid-Infrared Imaging (MIRI) instrument shows the Sagittarius B2 region (Sgr B2) in mid-infrared light, where warm dust glows brightly. RELATED ARTICLES
— Fly among 44 million stars in the latest 3D map of our galaxy, produced by the Gaia telescope — Space Photo of the Week
— The James Webb Space Telescope's “Starry Mountaintop” could be the observatory's best image to date — Space Photo of the Week
— The James Webb Space Telescope has discovered a deformed “butterfly star” shedding its chrysalis — Space Photo of the Week
Why Sagittarius B2 is so productive compared to the rest of the galactic center remains a mystery, but there are clues. On the right side of the MIRI image is a very bright red region rich in molecular material. This may be key to understanding why the cloud outpaces star formation throughout the galactic center, potentially rethinking theories of galaxy growth and evolution. Scientists plan to use Webb's new data on Sagittarius B2 to determine how long it has been forming stars and whether any specific event triggered its frenetic activity.
Find even more stunning space images in our Space Photos of the Week archive.
TOPICS Space Photo of the Week James Webb Space Telescope
Jamie Carter, Social Link Navigator, Live Science Contributor
Jamie Carter is a freelance journalist and regular Live Science contributor from Cardiff, UK. He is the author of “Stargazing for Beginners” and lectures on astronomy and nature. Jamie regularly writes for Space.com, TechRadar.com, Forbes Science, BBC Wildlife magazine, Scientific American, and many other publications. He edits the website WhenIsTheNextEclipse.com.
You must verify your public display name before commenting.
Please log out and log back in. You will then be asked to enter a display name.
Exit Read more
The James Webb and Hubble telescopes join forces to explore the cosmic hotbed: Space Photo of the Week
Fly among 44 million stars in the latest 3D map of our galaxy from the Gaia telescope – Space Photo of the Week
The James Webb Space Telescope has discovered stunning galaxies in the Bullet Cluster: Space Photo of the Week
The James Webb Space Telescope has captured one of the deepest images of the Universe yet — Space Photo of the Week
A giant 'X' symbol appeared over Chile as two intersecting beams of light: Space Photo of the Week
This 200-Light-Year-Wide Structure May Power the Center of Our Galaxy: 'Nobody Suspected This Cloud Existed'
Latest astronomy news
Scientists say the mysterious cosmic explosion cannot be explained.
“If there's a space race, China is already winning”: NASA is unlikely to deliver Martian soil samples to Earth before China, experts say.
It's official: humans have discovered 6,000 planets outside the solar system.
Science Story: DART, humanity's first asteroid deflection mission, hits space rock in the face – September 26, 2022
The James Webb Space Telescope may have discovered an entirely new class of cosmic object: a black hole.
City-killer asteroid could be destroyed by nuclear explosion before it approaches the Moon
Latest news
The ancient Egyptian statue of “Messi,” found in the Saqqara necropolis, is “the only known example of its kind from the Old Kingdom.”
Hurricane Fujiwara's rare 'dance' could spare the East Coast from the worst impacts of Tropical Storm Imelda
The study found that Iran is among the “world's most subsiding hotspots,” with some areas sinking by up to 30 cm per year.
A 30,000-year-old “personal toolkit” discovered in the Czech Republic offers a “very rare” glimpse into the life of a Stone Age hunter-gatherer.
Is acetaminophen safe during pregnancy? Here's what the science says.
Physicists have found a loophole in Heisenberg's uncertainty principle without violating it
LATEST ARTICLES
1The study found that Iran is among the “world's most extreme subsidence hotspots,” with some areas sinking by up to 30 cm per year.
Live Science magazine is part of Future US Inc., an international media group and leading digital publisher. Visit our corporate website.
- About Us
- Contact Future experts
- Terms and Conditions
- Privacy Policy
- Cookie Policy
- Accessibility Statement
- Advertise with us
- Web notifications
- Career
- Editorial standards
- How to present history to us
© Future US, Inc. Full 7th Floor, 130 West 42nd Street, New York, NY 10036.
var dfp_config = { “site_platform”: “vanilla”, “keywords”: “type-regular,serversidehawk,van-enable-adviser-
Sourse: www.livescience.com
