Members Can Post Anonymously On This Site
Webb makes first detection of crucial carbon molecule in a planet-forming disc
-
Similar Topics
-
By European Space Agency
The European Space Agency (ESA) has signed a contract with Thales Alenia Space in Italy to lead European aerospace companies in building the Argonaut Lunar Descent Element, ESA’s first lunar lander.
View the full article
-
By NASA
On Jan. 24, 1985, space shuttle Discovery took off from NASA’s Kennedy Space Center (KSC) in Florida on STS-51C, the first space shuttle mission entirely dedicated to the Department of Defense (DOD). As such, many of the details of the flight remain classified. Discovery’s crew of Commander Thomas “T.K.” Mattingly, Pilot Loren Shriver, Mission Specialists Ellison Onizuka and James Buchli, and Payload Specialist Gary Payton deployed a classified satellite that used an Inertial Upper Stage (IUS) to reach its final geostationary orbit. The three-day mission ended with a landing at KSC. Postflight inspection of the Solid Rocket Boosters (SRBs) revealed the most significant erosion of O-ring seals seen in the shuttle program up to that time, attributed to unusually cold weather before and during launch.
The STS-51C crew of Pilot Loren Shriver, seated left, and Commander Thomas “T.K.” Mattingly; Payload Specialist Gary Payton, standing left, and Mission Specialists James Buchli and Ellison Onizuka. The STS-51C crew patch. In October 1982, NASA assigned astronauts Mattingly, Shriver, Onizuka, and Buchli as the STS-10 crew for a dedicated DOD flight aboard Challenger then scheduled for September 1983. Payton joined the crew as a payload specialist in the summer of 1983 with Keith Wright assigned as his backup. The failure of the IUS on STS-6 in April 1983 delayed the STS-10 mission, that also used the IUS, until engineers could identify and fix the cause of the problem. By September 1983, NASA had remanifested the crew and the payload on STS-41F with a July 1984 launch, that changed to STS-41E by November 1983. Additional delays in fixing the IUS delayed the mission yet again, by June 1984 redesignated as STS-51C and slated for December 1984 aboard Challenger.
STS-51C marked the third spaceflight for Mattingly, selected in 1966 as part of NASA’s fifth group of astronauts. He served on the prime crew for Apollo 13 until exposure to German measles forced his last-minute replacement by his backup. He then flew on Apollo 16 and STS-4. For Shriver, Onizuka, and Buchli, all three selected as astronauts in the class of 1978, STS-51C marked their first trip into space. The U.S. Air Force selected Payton and Wright in August 1979 in its first class of Manned Spaceflight Engineers, and STS-51C marked Payton’s first and only space mission.
In November 1984, NASA decided to delay STS-51C from December 1984 to January 1985 and swap orbiters from Challenger to Discovery. Postflight inspections following Challenger’s STS-41G mission in October 1984 revealed degradation of the bonding materials holding thermal protection system tiles onto the orbiter, requiring the replacement of 4,000 tiles. The time required to complete the work precluded a December launch. Tests conducted on Discovery prior to its November STS-51A mission revealed the bonding material to be sound.
Space shuttle Discovery rolls out to Launch Pad 39A. The STS-51C crew poses during launch pad evacuation drills associated with the Terminal Countdown Demonstration Test. The STS-51C crew exits crew quarters for the ride to Launch Pad 39A. On Jan. 5, 1985, Discovery rolled out from KSC’s Vehicle Assembly Building, where workers mated it with its External Tank (ET) and SRBs, to Launch Pad 39A. There, engineers conducted the Terminal Countdown Demonstration Test, essentially a dress rehearsal for the actual countdown, on Jan. 6-7, with the crew participating in the final few hours much as they would on launch day. The astronauts returned to KSC on Jan. 20 to prepare for the planned launch on Jan. 23. The day before, NASA managers decided to delay the launch by one day due to unseasonably cold weather, with concern about sub-freezing temperatures causing ice to form on the ET and possibly coming loose during ascent and damaging the vehicle. The DOD had requested that NASA keep the actual launch time secret until T minus nine minutes, with most of the countdown taking place hidden from public view.
Liftoff of space shuttle Discovery on STS-51C. Liftoff of Discovery on its third mission, STS-51C, came at 2:50 p.m. EST on Jan. 24, beginning the 15th space shuttle flight. Eight and a half minutes later, Discovery and its five-man crew had reached orbit. And, at the DOD customer’s request, all public coverage of the mission ended. Although NASA could not reveal the spacecraft’s orbital parameters, trade publications calculated that Discovery first entered an elliptical orbit, circularized over the next few revolutions, prior to Onizuka deploying the IUS and payload combination on the seventh orbit. Neither NASA nor the DOD have released any imagery of the deployment or even of the payload bay, with only a limited number of in-cabin and Earth observation photographs made public.
STS-51C Commander Thomas “T.K.” Mattingly films the Earth from Discovery’s overhead flight deck window. STS-51C crew members Loren Shriver, left, Ellison Onizuka, and James Buchli on Discovery’s flight deck. STS-51C Payload Specialist Gary Payton on Discovery’s flight deck. Sunlight streams through Earth’s upper atmosphere, with Discovery’s tail and Orbital Maneuvering Engine pods outlined by sunlight. The Pacific coast of Guatemala and southern Mexico. New Orleans and the Mississippi River delta. Discovery touches down at NASA’s Kennedy Space Center in Florida. The STS-51C astronauts are greeted by NASA officials as they exit Discovery. To maintain the mission’s secrecy, NASA could reveal the touchdown time only 16 hours prior to the event. On Jan. 27, Mattingly and Shriver brought Discovery to a smooth landing at KSC’s Shuttle Landing Facility after a flight of three days one hour 33 minutes, the shortest space shuttle mission except for the first two orbital test flights. The astronauts orbited the Earth 49 times. About an hour after touchdown, the astronaut crew exited Discovery and boarded the Astrovan for the ride back to crew quarters. Neither NASA management nor the astronauts held a post mission press conference. The U.S. Air Force announced only that the “IUS aboard STS-51C was deployed from the shuttle Discovery and successfully met its mission objectives.” Later in the day, ground crews towed Discovery to the Orbiter Processing Facility to begin preparing it for its next planned mission, STS-51D in March.
Postscript
Following the recovery of SRBs after each shuttle mission, engineers conducted detailed inspections before clearing them for reuse. After STS-51C, inspections of the critical O-ring seals that prevented hot gases from escaping from the SRB field joints revealed significant erosion and “blow-by” between the primary and secondary O-rings. Both left and right hand SRBs showed this erosion, the most significant of the program up to that time. Importantly, these O-rings experienced weather colder than any previous shuttle mission, with overnight ambient temperatures in the teens and twenties. Even at launch time, the O-rings had reached only 60 degrees. Engineers believed that these cold temperatures made the O-rings brittle and more susceptible to erosion. One year later, space shuttle Challenger launched after similarly cold overnight temperatures, with O-rings at 57 degrees at launch time. The Rogers Commission report laid the blame of the STS-51L accident on the failure of O-rings that allowed super-hot gases to escape from the SRB and impinge on the hydrogen tank in the ET, resulting in the explosion that destroyed the orbiter and claimed the lives of seven astronauts. The commission also faulted NASA’s safety culture for not adequately addressing the issue of O-ring erosion, a phenomenon first observed on STS-2 and to varying degrees on several subsequent missions.
View the full article
-
By NASA
On Jan. 19, 1965, Gemini 2 successfully completed the second of two uncrewed test flights of the spacecraft and its Titan II booster, clearing the way for the first crewed mission. The 18-minute suborbital mission achieved the primary goals of flight qualifying the Gemini spacecraft, especially its heat shield during a stressful reentry. Recovery forces retrieved the capsule following its splashdown, allowing engineers to evaluate how its systems fared during the flight. The success of Gemini 2 enabled the first crewed mission to fly two months later, beginning a series of 10 flights over the following 20 months. The astronauts who flew these missions demonstrated the rendezvous and docking techniques necessary to implement the Lunar Orbit Rendezvous method NASA chose for the Moon landing mission. They also proved that astronauts could work outside their spacecraft during spacewalks and that spacecraft and astronauts could function for at least eight days, the minimum time for a roundtrip lunar mission. The Gemini program proved critical to fulfill President John F. Kennedy’s goal of landing a man on the Moon and returning him safely to Earth before the end of the 1960s.
Cutaway diagram of the Gemini spacecraft. Workers at Launch Pad 19 lift Gemini 2 to mate it with its Titan II rocket. At Pad 19, engineers verify the flight simulators inside Gemini 2. Following the success of Gemini 1 in April 1964, NASA had hoped to fly the second mission before the end of the year and the first crewed mission by January 1965. The two stages of the Titan II rocket arrived at Cape Kennedy from the Martin Marietta factory in Baltimore on July 11, and workers erected it on Launch Pad 19 five days later. A lightning strike at the pad on Aug. 17 invalidated all previous testing and required replacement of some pad equipment. A series of three hurricanes in August and September forced workers to partially or totally unstack the vehicle before stacking it for the final time on Sept. 14. The Gemini 2 spacecraft arrived at Cape Kennedy from its builder, the McDonnell Company in St. Louis, on Sept. 21, and workers hoisted it to the top of the Titan II on Oct. 18. Technical issues delayed the spacecraft’s physical mating to the rocket until Nov. 5. These accumulated delays pushed the launch date back to Dec. 9.
The launch abort on Dec. 9, 1964. Liftoff of Gemini 2 from Launch Pad 19 on Jan. 19, 1965. Engineers in the blockhouse monitor the progress of the Titan II during the ascent. Fueling of the rocket began late on Dec. 8, and following three brief holds in the countdown, the Titan’s two first stage engines ignited at 11:41 a.m. EST on Dec. 9. and promptly shut down one second later. Engineers later determined that a cracked valve resulted in loss of hydraulic pressure, causing the malfunction detection system to switch to its backup mode, forcing a shutdown of the engines. Repairs meant a delay into the new year. On Jan. 19, 1965, following a mostly smooth countdown, Gemini 2 lifted off from Pad 19 at 9:04 a.m. EST.
The Mission Control Center (MCC) at NASA’s Kennedy Space Center in Florida. In the MCC, astronauts Eugene Cernan, left, Walter Schirra, Gordon Cooper, Donald “Deke” Slayton, and Virgil “Gus” Grissom monitor the Gemini 2 flight. In the Gemini Mission Control Center at NASA’s Kennedy Space Center in Florida, Flight Director Christopher C. Kraft led a team of flight controllers that monitored all aspects of the flight. At the Manned Spacecraft Center (MSC), now NASA’s Johnson Space Center in Houston, a team of controllers led by Flight Director John Hodge passively monitored the flight from the newly built Mission Control Center. They would act as observers for this flight and Gemini 3, the first crewed mission, before taking over full control with Gemini IV, and control all subsequent American human spaceflights. The Titan rocket’s two stages placed Gemini 2 into a suborbital trajectory, reaching a maximum altitude of 98.9 miles, with the vehicle attaining a maximum velocity of 16,709 miles per hour. Within a minute after separating from the Titan’s second stage, Gemini 2 executed a maneuver to orient its heat shield in the direction of flight to prepare for reentry. Flight simulators installed where the astronauts normally would sit controlled the maneuvers. About seven minutes after liftoff, Gemini 2 jettisoned its equipment section, followed by firing of the retrorockets, and then separation of the retrorocket section, exposing the spacecraft’s heat shield.
View from a camera mounted on a cockpit window during Gemini 2’s reentry. View from the cockpit window during Gemini 2’s descent on its parachute. Gemini 2 then began its reentry, the heat shield protecting the spacecraft from the 2,000-degree heat generated by friction with the Earth’s upper atmosphere. A pilot parachute pulled away the rendezvous and recovery section. At 10,000 feet, the main parachute deployed, and Gemini 2 descended to a splashdown 2,127 miles from its launch pad, after a flight of 18 minutes 16 seconds. The splashdown took place in the Atlantic Ocean about 800 miles east of San Juan, Puerto Rico, and 25 miles from the prime recovery ship, the U.S.S. Lake Champlain (CVS-39).
A U.S. Navy helicopter hovers over the Gemini 2 capsule following its splashdown as a diver jumps into the water. Sailors hoist Gemini 2 aboard the U.S.S. Lake Champlain. U.S. Navy helicopters delivered divers to the splashdown area, who installed a flotation collar around the spacecraft. The Lake Champlain pulled alongside, and sailors hoisted the capsule onto the carrier, securing it on deck one hour forty minutes after liftoff. The spacecraft appeared to be in good condition and arrived back at Cape Kennedy on Jan. 22 for a thorough inspection. As an added bonus, sailors recovered the rendezvous and recovery section. Astronaut Virgil “Gus” Grissom, whom along with John Young NASA had selected to fly the first crewed Gemini mission, said after the splashdown, “We now see the road clear to our flight, and we’re looking forward to it.” Flight Director Kraft called it “very successful.” Gemini Program Manager Charles Matthews predicted the first crewed mission could occur within three months. Gemini 3 actually launched on March 23.
Enjoy this NASA video of the Gemini 2 mission.
Postscript
The Gemini-B capsule and a Manned Orbiting Laboratory (MOL) mockup atop a Titan-IIIC rocket in 1966. The flown Gemini-B capsule on display at the Cape Canaveral Space Force Museum in Florida. Former MOL and NASA astronaut Robert Crippen stands beside the only flown Gemini-B capsule – note the hatch in the heat shield at top. Gemini 2 not only cleared the way for the first crewed Gemini mission and the rest of the program, it also took on a second life as a test vehicle for the U.S. Air Force’s Manned Orbiting Laboratory (MOL). The Air Force modified the spacecraft, including cutting a hatch through its heat shield, renamed it Gemini-B, and launched it on Nov. 3, 1966, atop a Titan IIIC rocket. The test flight successfully demonstrated the hatch in the heat shield design during the capsule’s reentry after a 33-minute suborbital flight. Recovery forces retrieved the Gemini-B capsule in the South Atlantic Ocean and returned it to the Air Force for postflight inspection. This marked the only repeat flight of an American spacecraft intended for human spaceflight until the advent of the space shuttle. Visitors can view Gemini 2/Gemini-B on display at the Cape Canaveral Space Force Museum.
View the full article
-
By NASA
Webb Webb News Latest News Latest Images Blog (offsite) Awards X (offsite – login reqd) Instagram (offsite – login reqd) Facebook (offsite- login reqd) Youtube (offsite) Overview About Who is James Webb? Fact Sheet Impacts+Benefits FAQ Science Overview and Goals Early Universe Galaxies Over Time Star Lifecycle Other Worlds Observatory Overview Launch Orbit Mirrors Sunshield Instrument: NIRCam Instrument: MIRI Instrument: NIRSpec Instrument: FGS/NIRISS Optical Telescope Element Backplane Spacecraft Bus Instrument Module Multimedia About Webb Images Images Videos What is Webb Observing? 3d Webb in 3d Solar System Podcasts Webb Image Sonifications Team International Team People Of Webb More For the Media For Scientists For Educators For Fun/Learning 6 Min Read NASA’s Webb Reveals Intricate Layers of Interstellar Dust, Gas
This shimmering cosmic curtain shows interstellar gas and dust that has been heated by the flashbulb explosion of a long-ago supernova. The gas then glows infrared light in what is known as a thermal light echo. As the supernova illumination travels through space at the speed of light, the echo appears to expand. NASA’s James Webb Space Telescope observed this light echo in the vicinity of the supernova remnant Cassiopeia A. Credits:
NASA, ESA, CSA, STScI, J. Jencson (Caltech/IPAC) Once upon a time, the core of a massive star collapsed, creating a shockwave that blasted outward, ripping the star apart as it went. When the shockwave reached the star’s surface, it punched through, generating a brief, intense pulse of X-rays and ultraviolet light that traveled outward into the surrounding space. About 350 years later, that pulse of light has reached interstellar material, illuminating it, warming it, and causing it to glow in infrared light.
NASA’s James Webb Space Telescope has observed that infrared glow, revealing fine details resembling the knots and whorls of wood grain. These observations are allowing astronomers to map the true 3D structure of this interstellar dust and gas (known as the interstellar medium) for the first time.
“We were pretty shocked to see this level of detail,” said Jacob Jencson of Caltech/IPAC in Pasadena, principal investigator of the science program.
“We see layers like an onion,” added Josh Peek of the Space Telescope Science Institute in Baltimore, a member of the science team. “We think every dense, dusty region that we see, and most of the ones we don’t see, look like this on the inside. We just have never been able to look inside them before.”
The team is presenting their findings in a press conference at the 245th meeting of the American Astronomical Society in Washington.
“Even as a star dies, its light endures—echoing across the cosmos. It’s been an extraordinary three years since we launched NASA’s James Webb Space Telescope. Every image, every discovery, shows a portrait not only of the majesty of the universe but the power of the NASA team and the promise of international partnerships. This groundbreaking mission, NASA’s largest international space science collaboration, is a true testament to NASA’s ingenuity, teamwork, and pursuit of excellence,” said NASA Administrator Bill Nelson. “What a privilege it has been to oversee this monumental effort, shaped by the tireless dedication of thousands of scientists and engineers around the globe. This latest image beautifully captures the lasting legacy of Webb—a keyhole into the past and a mission that will inspire generations to come.”
Image A: Light Echoes Near Cassiopeia A (NIRCam)
These shimmering cosmic curtains show interstellar gas and dust that has been heated by the flashbulb explosion of a long-ago supernova. The gas then glows infrared light in what is known as a thermal light echo. As the supernova illumination travels through space at the speed of light, the echo appears to expand. NASA’s James Webb Space Telescope observed this light echo in the vicinity of the supernova remnant Cassiopeia A three separate times, in essence creating a 3D scan of the interstellar material. Note that the field of view in the top row is rotated slightly clockwise relative to the middle and bottom rows, due to the roll angle of the Webb telescope when the observations were taken. NASA, ESA, CSA, STScI, J. Jencson (Caltech/IPAC) Video A: Light Echoes Near Cassiopeia A (NIRCam)
This time-lapse video using data from NASA’s James Webb Space Telescope highlights the evolution of one light echo in the vicinity of the supernova remnant Cassiopeia A. A light echo is created when a star explodes or erupts, flashing light into surrounding clumps of interstellar dust and causing them to shine in an ever-expanding pattern. Webb’s exquisite resolution not only shows incredible detail within these light echoes, but also shows their expansion over the course of just a few weeks – a remarkably short timescale considering that most cosmic targets remain unchanged over a human lifetime.
Credit: NASA, ESA, CSA, STScI, J. Jencson (Caltech/IPAC) Taking a CT Scan
The images from Webb’s NIRCam (Near-Infrared Camera) highlight a phenomenon known as a light echo. A light echo is created when a star explodes or erupts, flashing light into surrounding clumps of dust and causing them to shine in an ever-expanding pattern. Light echoes at visible wavelengths (such as those seen around the star V838 Monocerotis) are due to light reflecting off of interstellar material. In contrast, light echoes at infrared wavelengths are caused when the dust is warmed by energetic radiation and then glows.
The researchers targeted a light echo that had previously been observed by NASA’s retired Spitzer Space Telescope. It is one of dozens of light echoes seen near the Cassiopeia A supernova remnant – the remains of the star that exploded. The light echo is coming from unrelated material that is behind Cassiopeia A, not material that was ejected when the star exploded.
The most obvious features in the Webb images are tightly packed sheets. These filaments show structures on remarkably small scales of about 400 astronomical units, or less than one-hundredth of a light-year. (An astronomical unit, or AU, is the average Earth-Sun distance. Neptune’s orbit is 60 AU in diameter.)
“We did not know that the interstellar medium had structures on that small of a scale, let alone that it was sheet-like,” said Peek.
These sheet-like structures may be influenced by interstellar magnetic fields. The images also show dense, tightly wound regions that resemble knots in wood grain. These may represent magnetic “islands” embedded within the more streamlined magnetic fields that suffuse the interstellar medium.
“This is the astronomical equivalent of a medical CT scan,” explained Armin Rest of the Space Telescope Science Institute, a member of the science team. “We have three slices taken at three different times, which will allow us to study the true 3D structure. It will completely change the way we study the interstellar medium.”
Image B: Cassiopeia A (Spitzer with Webb Insets)
This background image of the region around supernova remnant Cassiopeia A was released by NASA’s Spitzer Space Telescope in 2008. By taking multiple images of this region over three years with Spitzer, researchers were able to examine a number of light echoes. Now, NASA’s James Webb Space Telescope has imaged some of these light echoes in much greater detail. Insets at lower right show one epoch of Webb observations, while the inset at left shows a Webb image of the central supernova remnant released in 2023. Spitzer Image: NASA/JPL-Caltech/Y. Kim (Univ. of Arizona/Univ. of Chicago). Cassiopeia A Inset: NASA, ESA, CSA, STScI, Danny Milisavljevic (Purdue University), Ilse De Looze (UGent), Tea Temim (Princeton University). Light Echoes Inset: NASA, ESA, CSA, STScI, J. Jencson (Caltech/IPAC). Future Work
The team’s science program also includes spectroscopic observations using Webb’s MIRI (Mid-Infrared Instrument). They plan to target the light echo multiple times, weeks or months apart, to observe how it evolves as the light echo passes by.
“We can observe the same patch of dust before, during, and after it’s illuminated by the echo and try to look for any changes in the compositions or states of the molecules, including whether some molecules or even the smallest dust grains are destroyed,” said Jencson.
Infrared light echoes are also extremely rare, since they require a specific type of supernova explosion with a short pulse of energetic radiation. NASA’s upcoming Nancy Grace Roman Space Telescope will conduct a survey of the galactic plane that may find evidence of additional infrared light echoes for Webb to study in detail.
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
Downloads
Right click any image to save it or open a larger version in a new tab/window via the browser’s popup menu.
View/Download all image products at all resolutions for this article from the Space Telescope Science Institute.
Media Contacts
Laura Betz – laura.e.betz@nasa.gov
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Christine Pulliam – cpulliam@stsci.edu
Space Telescope Science Institute, Baltimore, Md.
Science – Jacob Jencson (Caltech/IPAC)
Related Information
Articles: Past Webb news releases on Cassiopeia A
Interactive: Explore light echoes in V838 Monocerotis
Videos: Learn more about supernovas.
More Webb News
More Webb Images
Webb Science Themes
Webb Mission Page
Related For Kids
What is a supernova?
What is the Webb Telescope?
SpacePlace for Kids
En Español
Ciencia de la NASA
NASA en español
Space Place para niños
Keep Exploring Related Topics
James Webb Space Telescope
Webb is the premier observatory of the next decade, serving thousands of astronomers worldwide. It studies every phase in the…
Stars Stories
Universe
Spitzer Space Telescope
Spitzer uses an ultra-sensitive infrared telescope to study asteroids, comets, planets and distant galaxies.
Share
Details
Last Updated Jan 14, 2025 Editor Marty McCoy Contact Laura Betz laura.e.betz@nasa.gov Related Terms
Astrophysics Goddard Space Flight Center James Webb Space Telescope (JWST) Nebulae Science & Research Supernova Remnants Supernovae The Universe View the full article
-
By NASA
Webb Webb News Latest News Latest Images Blog (offsite) Awards X (offsite – login reqd) Instagram (offsite – login reqd) Facebook (offsite- login reqd) Youtube (offsite) Overview About Who is James Webb? Fact Sheet Impacts+Benefits FAQ Science Overview and Goals Early Universe Galaxies Over Time Star Lifecycle Other Worlds Observatory Overview Launch Orbit Mirrors Sunshield Instrument: NIRCam Instrument: MIRI Instrument: NIRSpec Instrument: FGS/NIRISS Optical Telescope Element Backplane Spacecraft Bus Instrument Module Multimedia About Webb Images Images Videos What is Webb Observing? 3d Webb in 3d Solar System Podcasts Webb Image Sonifications Team International Team People Of Webb More For the Media For Scientists For Educators For Fun/Learning 6 Min Read Newfound Galaxy Class May Indicate Early Black Hole Growth, Webb Finds
A team of astronomers sifted through James Webb Space Telescope data from multiple surveys to compile one of the largest samples of “little red dots” to date. Credits:
NASA, ESA, CSA, STScI, Dale Kocevski (Colby College). In December 2022, less than six months after commencing science operations, NASA’s James Webb Space Telescope revealed something never seen before: numerous red objects that appear small on the sky, which scientists soon called “little red dots” (LRDs). Though these dots are quite abundant, researchers are perplexed by their nature, the reason for their unique colors, and what they convey about the early universe.
A team of astronomers recently compiled one of the largest samples of LRDs to date, nearly all of which existed during the first 1.5 billion years after the big bang. They found that a large fraction of the LRDs in their sample showed signs of containing growing supermassive black holes.
“We’re confounded by this new population of objects that Webb has found. We don’t see analogs of them at lower redshifts, which is why we haven’t seen them prior to Webb,” said Dale Kocevski of Colby College in Waterville, Maine, and lead author of the study. “There’s a substantial amount of work being done to try to determine the nature of these little red dots and whether their light is dominated by accreting black holes.”
Image A: Little Red Dots (NIRCam Image)
A team of astronomers sifted through James Webb Space Telescope data from multiple surveys to compile one of the largest samples of “little red dots” to date. From their sample, they found that these mysterious red objects that appear small on the sky emerge in large numbers around 600 million years after the big bang and undergo a rapid decline in quantity around 1.5 billion years after the big bang. NASA, ESA, CSA, STScI, Dale Kocevski (Colby College). A Potential Peek Into Early Black Hole Growth
A significant contributing factor to the team’s large sample size of LRDs was their use of publicly available Webb data. To start, the team searched for these red sources in the Cosmic Evolution Early Release Science (CEERS) survey before widening their scope to other extragalactic legacy fields, including the JWST Advanced Deep Extragalactic Survey (JADES) and the Next Generation Deep Extragalactic Exploratory Public (NGDEEP) survey.
The methodology used to identify these objects also differed from previous studies, resulting in the census spanning a wide redshift range. The distribution they discovered is intriguing: LRDs emerge in large numbers around 600 million years after the big bang and undergo a rapid decline in quantity around 1.5 billion years after the big bang.
The team looked toward the Red Unknowns: Bright Infrared Extragalactic Survey (RUBIES) for spectroscopic data on some of the LRDs in their sample. They found that about 70 percent of the targets showed evidence for gas rapidly orbiting 2 million miles per hour (1,000 kilometers per second) – a sign of an accretion disk around a supermassive black hole. This suggests that many LRDs are accreting black holes, also known as active galactic nuclei (AGN).
“The most exciting thing for me is the redshift distributions. These really red, high-redshift sources basically stop existing at a certain point after the big bang,” said Steven Finkelstein, a co-author of the study at the University of Texas at Austin. “If they are growing black holes, and we think at least 70 percent of them are, this hints at an era of obscured black hole growth in the early universe.”
Contrary to Headlines, Cosmology Isn’t Broken
When LRDs were first discovered, some suggested that cosmology was “broken.” If all of the light coming from these objects was from stars, it implied that some galaxies had grown so big, so fast, that theories could not account for them.
The team’s research supports the argument that much of the light coming from these objects is from accreting black holes and not from stars. Fewer stars means smaller, more lightweight galaxies that can be understood by existing theories.
“This is how you solve the universe-breaking problem,” said Anthony Taylor, a co-author of the study at the University of Texas at Austin.
Curiouser and Curiouser
There is still a lot up for debate as LRDs seem to evoke even more questions. For example, it is still an open question as to why LRDs do not appear at lower redshifts. One possible answer is inside-out growth: As star formation within a galaxy expands outward from the nucleus, less gas is being deposited by supernovas near the accreting black hole, and it becomes less obscured. In this case, the black hole sheds its gas cocoon, becomes bluer and less red, and loses its LRD status.
Additionally, LRDs are not bright in X-ray light, which contrasts with most black holes at lower redshifts. However, astronomers know that at certain gas densities, X-ray photons can become trapped, reducing the amount of X-ray emission. Therefore, this quality of LRDs could support the theory that these are heavily obscured black holes.
The team is taking multiple approaches to understand the nature of LRDs, including examining the mid-infrared properties of their sample, and looking broadly for accreting black holes to see how many fit LRD criteria. Obtaining deeper spectroscopy and select follow-up observations will also be beneficial for solving this currently “open case” about LRDs.
“There’s always two or more potential ways to explain the confounding properties of little red dots,” said Kocevski. “It’s a continuous exchange between models and observations, finding a balance between what aligns well between the two and what conflicts.”
These results were presented in a press conference at the 245th meeting of the American Astronomical Society in National Harbor, Maryland, and have been submitted for publication in The Astrophysical Journal.
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
Downloads
Right click any image to save it or open a larger version in a new tab/window via the browser’s popup menu.
View/Download all image products at all resolutions for this article from the Space Telescope Science Institute.
Media Contacts
Laura Betz – laura.e.betz@nasa.gov
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Abigail Major – amajor@stsci.edu, Christine Pulliam – cpulliam@stsci.edu
Space Telescope Science Institute, Baltimore, Md.
Science – Dale Kocevski (Colby College)
Related Information
3D visualization: CEERS Fly Through visualization and JADES GOODS South Fly Through visualization
Graphic: What is cosmological redshift?
Graphic: Dissecting Supermassive Black Holes
Article: Webb Science: Galaxies Through Time
Web Page: Learn more about black holes
More Webb News
More Webb Images
Webb Science Themes
Webb Mission Page
Related For Kids
What is a Black Hole?
What is the Webb Telescope?
SpacePlace for Kids
En Español
Ciencia de la NASA
NASA en español
Space Place para niños
Keep Exploring Related Topics
James Webb Space Telescope
Webb is the premier observatory of the next decade, serving thousands of astronomers worldwide. It studies every phase in the…
Galaxies
Black Holes
Universe
Share
Details
Last Updated Jan 14, 2025 Editor Stephen Sabia Contact Laura Betz laura.e.betz@nasa.gov Related Terms
Astrophysics Black Holes Galaxies Galaxies, Stars, & Black Holes Goddard Space Flight Center James Webb Space Telescope (JWST) Science & Research Supermassive Black Holes The Universe View the full article
-
-
Check out these Videos
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.