ESA/Webb/NASA/CSA
This composite image of nebula NGC 1333 captures minute detail of young stars and brown dwarfs. These details were previously obscured in Hubble Telescope's images of the same nebula.
NASA/ESA/CSA/M. Marin (STScI)
NASA released this image of galaxy Arp 142 on July 12, to mark the two-year anniversary of the James Webb Space Telescope.
NASA, ESA, CSA, STScI, J. Lee (STScI), T. Williams (Oxford), PHANGS Team
This Webb image shows a densely populated spiral galaxy anchored by a central region that has a light blue haze, known NGC 628. It's 32 million light-years away in the constellation Pisces.
NASA/ESA/CSA/ STScI
In this new image of Uranus, the planet shines shine brightly, along with its many rings and moons.
NASA/ESA/CSA/STScI
The James Webb Space Telescope's shot of supernova remnant Cassiopeia A shows elaborate details visible for the first time.
NASA/ESA/CSA/STScI
There are approximately 500,000 stars in this image of the Sagittarius C region of the Milky Way. The bright cyan area contains emissions from ionized hydrogen.
NASA/ESA/CSA/STScI
Galaxy cluster MACS0416 is seen here in exquisite detail thanks to a composite image created with data from both NASA's James Webb and Hubble space telescopes.
NASA/ESA/CSA/STScI/Tea Temim
Scientists are hoping to gain more information about the origins of the Crab Nebula, thanks to new details spotted by the James Webb Space Telescope.
ESA/Webb/NASA/CSA
This image shows the Ring Nebula in exceptional detail, like the filament elements in the ring's inner section.
NASA/ESA/CSA
Earendel, the most distant star ever discovered, can be seen in this image of the Sunrise Arc galaxy.
NASA/ESA/CSA/JWST Ring Nebula Team
The Ring Nebula is seen in breathtaking detail, in a composite image released on August 4.
J. DePasquale/CSA/ESA/NASA
The James Webb Space Telescope captured a high-resolution image of a pair of actively forming stars called Herbig-Haro 46/47. The stellar duo, only a few thousand years old, is located at the center of the red diffraction spikes.
NASA/ESA/CSA/Klaus Pontoppidan, STScI
The James Webb Space Telescope captured a detailed closeup of the birth of sunlike stars in the Rho Ophiuchi cloud, the closest star-forming region located 390 light-years from Earth. The young stars release jets that cause the surrounding gas to glow. The image's release marks the first anniversary of Webb's observations of the cosmos.
NASA
Saturn and its moons were captured by NASA's James Webb Space Telescope June 25. The image shows details of the planet's atmosphere and ring system.
ESA/Webb/NASA/CSA
The James Webb Space Telescope captured the Orion Bar, a part of the Orion Nebula that is being eroded by stellar radiation emanating from the Trapezium Cluster.
NASA/ESA/CSA
This composite image, shot from the James Webb Space Telescope's MIRI and NIRCam instruments, shows the bright clusters of stars and dust from barred spiral galaxy NGC 5068.
NASA/ESA/CSA/STScI
Webb captured a burst of star formation triggered by two colliding spiral galaxies called Arp 220. The phenomenon is the closest ultra-luminous galactic merger to Earth.
NASA/ESA/CSA/A. Pagan/A. Gáspár
Dusty rings surround Fomalhaut, a young star outside of our solar system that's 25 light-years from Earth.
NASA/ESA/CSA/STScI/Webb ERO Production Team
The Wolf-Rayet star WR 124 was one of the James Webb Space Telescope's first discoveries, spotted in June 2022.
NASA/ESA/CSA/D. D. Milisavljevic/T. Temim/I. De Looze
Stunning details can be seen in this Webb telescope photo of supernova remnant Cassiopeia A, which is 11,000 light-years from Earth.
Space Telescope Science Institut/STScI
Webb's image of ice giant Uranus shows off the planet's incredible rings and a bright haze covering its north polar cap (right). A bright cloud lies at the cap's edge and a second one is seen at left.
NASA/ESA/CSA/STScI
The James Webb Space Telescope captured 50,000 sources of near-infrared light in a new image of Pandora's Cluster, a megacluster of galaxies. The cluster acts like a magnifying glass, allowing astronomers to see more distant galaxies behind it.
NASA/ESA/CSA
Stars shine through the hazy material of the Chamaeleon I dark molecular cloud, which is 630 light-years away from Earth.
NASA/ESA/CSA/STScI/A. Pagan
The James Webb Space Telescope spotted NGC 346, one of the most dynamic star-forming regions near the Milky Way, located in a dwarf galaxy called the Small Magellanic Cloud.
NASA/ESA
Two galaxies, known as II ZW96, form a swirl shape while merging in the constellation Delphinus.
NASA/ESA/CSA/STScI
The James Webb Space Telescope revealed features of a new protostar forming.
NASA/ESA/CSA/STScI
The James Webb Space Telescope captured a new perspective of the Pillars of Creation in mid-infrared light. The dust of this star-forming region, rather than the stars themselves, is the highlight, and resembles ghostly figures.
NASA/ESA/CSA/STScI
Webb captured a highly detailed snapshot of the so-called Pillars of Creation, a vista of three looming towers made of interstellar dust and gas that's speckled with newly formed stars. The area, which lies within the Eagle Nebula about 6,500 light-years from Earth, had previously been captured by the Hubble Telescope in 1995, creating an image deemed "iconic" by space observers.
NASA/ESA/CSA/STScI/JPL-Caltech
The two stars in WR140 produce shells of dust every eight years that look like rings, as captured by the Webb telescope.
NASA/ESA/CSA/ASU/UA/UM/JWST PEARLs Team
The James Webb Space Telescope and Hubble Space Telescope contributed to this image of galactic pair VV 191. Webb observed the brighter elliptical galaxy (left) and spiral galaxy (right) in near-infrared light, and Hubble collected data in visible and ultraviolet light.
ESA/NASA/CSA/J. Lee
The James Webb Space Telescope captured spiral galaxy IC 5332, which is over 29 million light-years away. The observatory's MIRI instrument peered through interstellar dust to see the galaxy's "bones."
NASA/ESA/CSA/STScI
Webb captured the clearest view of the Neptune's rings in over 30 years.
NASA/ESA/CSA/PDRS4all
The inner region of the Orion Nebula as seen by the telescope's NIRCam instrument. The image reveals intricate details about how stars and planetary systems are formed.
NASA/ESA/CSA/STScI/Webb ERO Production Team
NASA released a mosaic image of the Tarantula Nebula on Tuesday, September 6. The image, which spans 340 light-years, shows tens of thousands of young stars that were previously obscured by cosmic dust.
NASA/ESA
A new image of the Phantom Galaxy, which is 32 million light-years away from Earth, combines data from the James Webb Space Telescope and the Hubble Space Telescope.
NASA/ESA/CSA/Jupiter ERS Team
NASA released an image of Jupiter on Monday, August 22, that shows the planet's famous Great Red Spot appearing white.
NASA/ESA/CSA/STScI
The James Webb Space Telescope captured the Cartwheel galaxy, which is around 500 million light-years away, in a photo released by NASA on August 2.
NASA/ESA/CSA/STScI
Webb's landscape-like view, called "Cosmic Cliffs," is actually the edge of a nearby, young, star-forming region called NGC 3324 in the Carina Nebula. The telescope's infrared view reveals previously invisible areas of star birth.
NASA/ESA/CSA/STScI
The five galaxies of Stephan's Quintet can be seen here in a new light. The galaxies appear to dance with one another, showcasing how these interactions can drive galactic evolution.
NASA/ESA/CSA/STScI
This side-by-side comparison shows observations of the Southern Ring Nebula in near-infrared light, left, and mid-infrared light, right, from NASA's Webb telescope. The Southern Ring Nebula is 2,000 light-years away from Earth. This large planetary nebula includes an expanding cloud of gas around a dying star, as well as a secondary star earlier on in its evolution.
NASA/ESA/CSA/STScI
President Joe Biden released one of Webb's first images on July 11, and it's "the deepest and sharpest infrared image of the distant universe to date," according to NASA. The image shows SMACS 0723, where a massive group of galaxy clusters act as a magnifying glass for the objects behind them. Called gravitational lensing, this created Webb's first deep field view of incredibly old and distant, faint galaxies.

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CNN  — 

The James Webb Space Telescope has observed its smallest cosmic object to date — a previously unknown asteroid about the size of the Colosseum in Rome.

A team of European astronomers made the detection of the space rock, which is between 328 and 656 feet (100 to 200 meters) long, and located in the main asteroid belt between Mars and Jupiter.

The doughnut-shaped belt is home to most of the asteroids in the solar system. The main asteroid belt is in close alignment with the ecliptic plane, or the same plane that includes Earth’s orbit around the sun.

The asteroid may be one of the smallest ever found in the main belt. Such small, dark cosmic objects are incredibly hard to observe, but astronomers can use Webb to look for more asteroids of this size in the future.

Further observations will help astronomers learn more about the asteroid in the future and confirm that it is truly a newly discovered object.

The detection of the asteroid was made by chance when the Webb research team focused the telescope’s Mid-InfraRed Instrument, or MIRI, on the main belt asteroid (10920) 1998 BC1, originally discovered in 1998, to take calibration images.

“We — completely unexpectedly — detected a small asteroid in publicly available MIRI calibration observations,” said Thomas Müller, astronomer at the Max Planck Institute for Extraterrestrial Physics in Germany, in a statement. “The measurements are some of the first MIRI measurements targeting the ecliptic plane and our work suggests that many new objects will be detected with this instrument.”

N. Bartmann (ESA/Webb), ESO/M. Kornmesser and S. Brunier, N. Risinger
An artist's illustration depicts an irregularly shaped gray asteroid similar to the new object spotted by the Webb telescope.

Asteroids are the leftover remnants from the formation of the solar system, and astronomers have determined the location of more than 1.1 million of them.

Many asteroids still remain unknown — and Webb’s find hints that the powerful infrared telescope may uncover plenty more small, rocky objects that have otherwise escaped detection before.

A ‘failed’ observation’s silver lining

The calibration images the Webb research team took in their attempt to observe asteroid (10920) 1998 BC1 didn’t turn out as expected and were considered a technical failure because the object appeared so bright.

NASA/ESA/CSA
This image by the NASA/ESA/CSA James Webb Space Telescope's Near-InfraRed Camera (NIRCam) features the central region of the Chameleon I dark molecular cloud, which resides 630 light years away. The cold, wispy cloud material (blue, centre) is illuminated in the infrared by the glow of the young, outflowing protostar Ced 110 IRS 4 (orange, upper left). The light from numerous background stars, seen as orange dots behind the cloud, can be used to detect ices in the cloud, which absorb the starlight passing through them.  An international team of astronomers has reported the discovery of diverse ices in the darkest, coldest regions of a molecular cloud measured to date by studying this region. This result allows astronomers to examine the simple icy molecules that will be incorporated into future exoplanets, while opening a new window on the origin of more complex molecules that are the first step in the creation of the building blocks of life. [Image Description: A large, dark cloud is contained within the frame. In its top half it is textured like smoke and has wispy gaps, while at the bottom and at the sides it fades gradually out of view. On the left are several orange stars: three each with six large spikes, and one behind the cloud which colours it pale blue and orange. Many tiny stars are visible, and the background is black.]

Webb telescope peers into the frozen heart of a space cloud

The astronomers were still able to use the data to test a new technique for determining an asteroid’s orbit and size. The observations of (10920) 1998 BC1 were combined with data from the European Space Agency’s Gaia mission and ground-based telescopes.

While analyzing the data, the researchers spotted an “interloper” in their observations — the new asteroid making its first appearance.

“Our results show that even ‘failed’ Webb observations can be scientifically useful, if you have the right mindset and a little bit of luck,” Müller said. “Our detection lies in the main asteroid belt, but Webb’s incredible sensitivity made it possible to see this roughly 100-metre object at a distance of more than 100 million kilometres.”

NASA/ESA/CSA
Based on new evidence from the NASA/ESA/CSA James Webb Space Telescope, this illustration reflects the conclusion that the exoplanet LHS 475 b is rocky and almost precisely the same size as Earth. The planet whips around its star in just two days, far faster than any planet in the Solar System. Researchers will follow up this summer with additional observations with Webb, which they hope will allow them to definitively conclude if the planet has an atmosphere. LHS 475 b is relatively close, 41 light-years away, in the constellation Octans. [Image Description: Illustration of a planet and its star on a black background. The planet is large, in the foreground at the centre, and the star is smaller, in the background and also at the centre. The planet is rocky. The top quarter of the planet (the side facing the star) is lit, while the rest is in shadow. The star is bright yellowish-white, with no clear features.]

James Webb Space Telescope discovers its first exoplanet

And astronomers won’t be surprised if other unknown space rocks photobomb future Webb images.

“This is a fantastic result which highlights the capabilities of MIRI to serendipitously detect a previously undetectable size of asteroid in the main belt,” said Bryan Holler, Webb support scientist at the Space Telescope Science Institute in Baltimore, in a statement. “Repeats of these observations are in the process of being scheduled, and we are fully expecting new asteroid interlopers in those images!”