Jump to content

In Odd Galaxy, NASA’s Webb Finds Potential Missing Link to First Stars


Recommended Posts

  • Publishers
Posted
4 Min Read

In Odd Galaxy, NASA’s Webb Finds Potential Missing Link to First Stars

A black background sprinkled with small, colorful galaxies in orange, blue, and white. On the left, a third of the way down from the top of the image, a very faint dot of a galaxy is outlined with a white square and pulled out in a graphic to be shown magnified. In the pullout square to the right, the galaxy is a hazy white dot edged in orange, with faint blue projections opposite each other at the 11 o’clock and 5 o’clock positions.
What appears as a faint dot in this James Webb Space Telescope image may actually be a groundbreaking discovery. Full image and details below.
Credits:
NASA, ESA, CSA, STScI, Alex Cameron (Oxford)

Looking deep into the early universe with NASA’s James Webb Space Telescope, astronomers have found something unprecedented: a galaxy with an odd light signature, which they attribute to its gas outshining its stars. Found approximately one billion years after the big bang, galaxy GS-NDG-9422 (9422) may be a missing-link phase of galactic evolution between the universe’s first stars and familiar, well-established galaxies.

Image A: Galaxy GS-NDG-9422 (NIRCam Image)

A black background sprinkled with small, colorful galaxies in orange, blue, and white. On the left, a third of the way down from the top of the image, a very faint dot of a galaxy is outlined with a white square and pulled out in a graphic to be shown magnified. In the pullout square to the right, the galaxy is a hazy white dot edged in orange, with faint blue projections opposite each other at the 11 o’clock and 5 o’clock positions.
What appears as a faint dot in this James Webb Space Telescope image may actually be a groundbreaking discovery. Detailed information on galaxy GS-NDG-9422, captured by Webb’s NIRSpec (Near-Infrared Spectrograph) instrument, indicates that the light we see in this image is coming from the galaxy’s hot gas, rather than its stars. Astronomers think that the galaxy’s stars are so extremely hot (more than 140,000 degrees Fahrenheit, or 80,000 degrees Celsius) that they are heating up the nebular gas, allowing it to shine even brighter than the stars themselves.
NASA, ESA, CSA, STScI, Alex Cameron (Oxford)

“My first thought in looking at the galaxy’s spectrum was, ‘that’s weird,’ which is exactly what the Webb telescope was designed to reveal: totally new phenomena in the early universe that will help us understand how the cosmic story began,” said lead researcher Alex Cameron of the University of Oxford.

Cameron reached out to colleague Harley Katz, a theorist, to discuss the strange data. Working together, their team found that computer models of cosmic gas clouds heated by very hot, massive stars, to an extent that the gas shone brighter than the stars, was nearly a perfect match to Webb’s observations.

“It looks like these stars must be much hotter and more massive than what we see in the local universe, which makes sense because the early universe was a very different environment,” said Katz, of Oxford and the University of Chicago.

In the local universe, typical hot, massive stars have a temperature ranging between 70,000 to 90,000 degrees Fahrenheit (40,000 to 50,000 degrees Celsius). According to the team, galaxy 9422 has stars hotter than 140,000 degrees Fahrenheit (80,000 degrees Celsius).

The research team suspects that the galaxy is in the midst of a brief phase of intense star formation inside a cloud of dense gas that is producing a large number of massive, hot stars. The gas cloud is being hit with so many photons of light from the stars that it is shining extremely brightly.

Image B: Galaxy GS-NDG-9422 Spectrum (NIRSpec)

Infographic titled Galaxy GS-NDG-9422, Nebular light outshines starlight. Graphic is divided horizontally with one spectrum on top, labeled Webb Data, and one on bottom, labeled Model Spectrum. A portion of both spectrums about an inch wide is highlighted with a vertical column labeled Slope Feature. There is a clear similarity between the top and bottom graphs, thought the top has more angular lines and the bottom is smoother and rounded. See extended description for more.
This comparison of the data collected by the James Webb Space Telescope with a computer model prediction highlights the same sloping feature that first caught the eye of astronomer Alex Cameron, lead researcher of a new study published in Monthly Notices of the Royal Astronomical Society.

The bottom graphic compares what astronomers would expect to see in a “typical” galaxy, with its light coming predominantly from stars (white line), with a theoretical model of light coming from hot nebular gas, outshining stars (yellow line). The model comes from Cameron’s collaborator, theoretical astronomer Harley Katz, and together they realized the similarities between the model and Cameron’s Webb observations of galaxy GS-NDG-9422 (top). The unusual downturn of the galaxy’s spectrum, leading to an exaggerated spike in neutral hydrogen, is nearly a perfect match to Katz’s model of a spectrum dominated by super-heated gas.

While this is still only one example, Cameron, Katz, and their fellow researchers think the conclusion that galaxy GS-NDG-9422 is dominated by nebular light, rather than starlight, is their strongest jumping-off point for future investigation. They are looking for more galaxies around the same one-billion-year mark in the universe’s history, hoping to find more examples of a new type of galaxy, a missing link in the history of galactic evolution.

NASA, ESA, CSA, Leah Hustak (STScI)

In addition to its novelty, nebular gas outshining stars is intriguing because it is something predicted in the environments of the universe’s first generation of stars, which astronomers classify as Population III stars.

“We know that this galaxy does not have Population III stars, because the Webb data shows too much chemical complexity. However, its stars are different than what we are familiar with – the exotic stars in this galaxy could be a guide for understanding how galaxies transitioned from primordial stars to the types of galaxies we already know,” said Katz.

At this point, galaxy 9422 is one example of this phase of galaxy development, so there are still many questions to be answered. Are these conditions common in galaxies at this time period, or a rare occurrence? What more can they tell us about even earlier phases of galaxy evolution? Cameron, Katz, and their research colleagues are actively identifying more galaxies to add to this population to better understand what was happening in the universe within the first billion years after the big bang.

“It’s a very exciting time, to be able to use the Webb telescope to explore this time in the universe that was once inaccessible,” Cameron said. “We are just at the beginning of new discoveries and understanding.”

The research paper is published in Monthly Notices of the Royal Astronomical Society.

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.

View/Download the research results from the Monthly Notices of the Royal Astronomical Society.

Media Contacts

Laura Betz – laura.e.betz@nasa.gov, Rob Gutrorob.gutro@nasa.gov
NASA’s Goddard Space Flight Center, Greenbelt, Md.

Christine Pulliamcpulliam@stsci.edu, Leah Ramsaylramsay@stsci.edu
Space Telescope Science Institute, Baltimore, Md.

Read more: “What Were the First Stars Like?”

Watch:Massive Stars: Engines of Creation

Learn about spectroscopy:Spectroscopy 101 – Introduction

Star Lifecycle

More Webb News

More Webb Images

Webb Science Themes

Webb Mission Page

What is a galaxy?

What is the Webb Telescope?

SpacePlace for Kids

En Español

Ciencia de la NASA

NASA en español 

Space Place para niños

Share

Details

Last Updated
Sep 24, 2024
Editor
Marty McCoy
Contact

View the full article

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.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Similar Topics

    • 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
      Hubble Space Telescope Hubble Home Overview About Hubble The History of Hubble Hubble Timeline Why Have a Telescope in Space? Hubble by the Numbers At the Museum FAQs Impact & Benefits Hubble’s Impact & Benefits Science Impacts Cultural Impact Technology Benefits Impact on Human Spaceflight Astro Community Impacts Science Hubble Science Science Themes Science Highlights Science Behind Discoveries Hubble’s Partners in Science Universe Uncovered Explore the Night Sky Observatory Hubble Observatory Hubble Design Mission Operations Missions to Hubble Hubble vs Webb Team Hubble Team Career Aspirations Hubble Astronauts News Hubble News Hubble News Archive Social Media Media Resources Multimedia Multimedia Images Videos Sonifications Podcasts e-Books Online Activities Lithographs Fact Sheets Glossary Posters Hubble on the NASA App More 35th Anniversary 2 min read
      Hubble Captures Young Stars Changing Their Environments
      This NASA/ESA Hubble Space Telescope image features the nearest star-forming region to Earth, the Orion Nebula (Messier 42, M42), located some 1,500 light-years away. ESA/Hubble, NASA, and T. Megeath This NASA/ESA Hubble Space Telescope image peers into the dusty recesses of the nearest massive star-forming region to Earth, the Orion Nebula (Messier 42, M42). Just 1,500 light-years away, the Orion Nebula is visible to the unaided eye below the three stars that form the ‘belt’ in the constellation Orion. The nebula is home to hundreds of newborn stars including the subject of this image: the protostars HOPS 150 and HOPS 153.
      These protostars get their names from the Herschel Orion Protostar Survey, conducted with ESA’s Herschel Space Observatory. The object visible in the upper-right corner of this image is HOPS 150: it’s a binary star system where two young protostars orbit each other. Each star has a small, dusty disk of material surrounding it. These stars gather material from their respective dust disks, growing in the process. The dark line that cuts across the bright glow of these protostars is a cloud of gas and dust falling in on the pair of protostars. It is over 2,000 times wider than the distance between Earth and the Sun. Based on the amount of infrared light HOPS 150 is emitting, as compared to other wavelengths it emits, the protostars are mid-way down the path to becoming mature stars.
      Extending across the left side of the image is a narrow, colorful outflow called a jet. This jet comes from the nearby protostar HOPS 153, which is out of the frame. HOPS 153 is significantly younger than its neighbor. That stellar object is still deeply embedded in its birth nebula and enshrouded by a cloud of cold, dense gas. While Hubble cannot penetrate this gas to see the protostar, the jet HOPS 153 emitted is brightly and clearly visible as it plows into the surrounding gas and dust of the Orion Nebula.
      The transition from tightly swaddled protostar to fully fledged star will dramatically affect HOPS 153’s surroundings. As gas falls onto the protostar, its jets spew material and energy into interstellar space, carving out bubbles and heating the gas. By stirring up and warming nearby gas, HOPS 153 may regulate the formation of new stars in its neighborhood and even slow its own growth.
      Facebook logo @NASAHubble @NASAHubble Instagram logo @NASAHubble Explore More

      Three-Year Study of Young Stars with NASA’s Hubble Enters New Chapter


      NASA’s Hubble Finds Sizzling Details About Young Star FU Orionis


      Bow Shock Near a Young Star

      Media Contact:
      Claire Andreoli (claire.andreoli@nasa.gov)
      NASA’s Goddard Space Flight Center, Greenbelt, MD
      Share








      Details
      Last Updated Jan 16, 2025 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center Related Terms
      Astrophysics Astrophysics Division Goddard Space Flight Center Hubble Space Telescope Nebulae Protostars Stars The Universe Keep Exploring Discover More Topics From Hubble
      Hubble Space Telescope


      Since its 1990 launch, the Hubble Space Telescope has changed our fundamental understanding of the universe.


      Exploring the Birth of Stars



      Hubble’s Night Sky Challenge



      Hubble Focus: The Lives of Stars


      This e-book highlights the mission’s recent discoveries and observations related to the birth, evolution, and death of stars.

      View the full article
    • By NASA
      Hubble Space Telescope Hubble Home Overview About Hubble The History of Hubble Hubble Timeline Why Have a Telescope in Space? Hubble by the Numbers At the Museum FAQs Impact & Benefits Hubble’s Impact & Benefits Science Impacts Cultural Impact Technology Benefits Impact on Human Spaceflight Astro Community Impacts Science Hubble Science Science Themes Science Highlights Science Behind Discoveries Hubble’s Partners in Science Universe Uncovered Explore the Night Sky Observatory Hubble Observatory Hubble Design Mission Operations Missions to Hubble Hubble vs Webb Team Hubble Team Career Aspirations Hubble Astronauts News Hubble News Hubble News Archive Social Media Media Resources Multimedia Multimedia Images Videos Sonifications Podcasts e-Books Online Activities Lithographs Fact Sheets Glossary Posters Hubble on the NASA App More 35th Anniversary 6 Min Read NASA’s Hubble Traces Hidden History of Andromeda Galaxy
      This photomosaic of the Andromeda galaxy is the largest ever assembled from Hubble observations. Credits:
      NASA, ESA, Benjamin F. Williams (UWashington), Zhuo Chen (UWashington), L. Clifton Johnson (Northwestern); Image Processing: Joseph DePasquale (STScI) In the years following the launch of NASA’s Hubble Space Telescope, astronomers have tallied over 1 trillion galaxies in the universe. But only one galaxy stands out as the most important nearby stellar island to our Milky Way — the magnificent Andromeda galaxy (Messier 31). It can be seen with the naked eye on a very clear autumn night as a faint cigar-shaped object roughly the apparent angular diameter of our Moon.
      A century ago, Edwin Hubble first established that this so-called “spiral nebula” was actually very far outside our own Milky Way galaxy — at a distance of approximately 2.5 million light-years or roughly 25 Milky Way diameters. Prior to that, astronomers had long thought that the Milky way encompassed the entire universe. Overnight, Hubble’s discovery turned cosmology upside down by unveiling an infinitely grander universe.
      Now, a century later, the space telescope named for Hubble has accomplished the most comprehensive survey of this enticing empire of stars. The Hubble telescope is yielding new clues to the evolutionary history of Andromeda, and it looks markedly different from the Milky Way’s history.
      This is largest photomosaic ever assembled from Hubble Space Telescope observations. It is a panoramic view of the neighboring Andromeda galaxy, located 2.5 million light-years away. It took over 10 years to make this vast and colorful portrait of the galaxy, requiring over 600 Hubble overlapping snapshots that were challenging to stitch together. The galaxy is so close to us, that in angular size it is six times the apparent diameter of the full Moon, and can be seen with the unaided eye. For Hubble’s pinpoint view, that’s a lot of celestial real estate to cover. This stunning, colorful mosaic captures the glow of 200 million stars. That’s still a fraction of Andromeda’s population. And the stars are spread across about 2.5 billion pixels. The detailed look at the resolved stars will help astronomers piece together the galaxy’s past history that includes mergers with smaller satellite galaxies. NASA, ESA, Benjamin F. Williams (UWashington), Zhuo Chen (UWashington), L. Clifton Johnson (Northwestern); Image Processing: Joseph DePasquale (STScI)
      Download this image (10,552 x 2,468)(9 MB)


      Download this image (42,208 x 9,870)(203 MB)

      Without Andromeda as a proxy for spiral galaxies in the universe at large, astronomers would know much less about the structure and evolution of our own Milky Way. That’s because we are embedded inside the Milky Way. This is like trying to understand the layout of New York City by standing in the middle of Central Park.
      “With Hubble we can get into enormous detail about what’s happening on a holistic scale across the entire disk of the galaxy. You can’t do that with any other large galaxy,” said principal investigator Ben Williams of the University of Washington. Hubble’s sharp imaging capabilities can resolve more than 200 million stars in the Andromeda galaxy, detecting only stars brighter than our Sun. They look like grains of sand across the beach. But that’s just the tip of the iceberg. Andromeda’s total population is estimated to be 1 trillion stars, with many less massive stars falling below Hubble’s sensitivity limit.
      Photographing Andromeda was a herculean task because the galaxy is a much bigger target on the sky than the galaxies Hubble routinely observes, which are often billions of light-years away. The full mosaic was carried out under two Hubble programs. In total, it required over 1,000 Hubble orbits, spanning more than a decade.
      This panorama started with the Panchromatic Hubble Andromeda Treasury (PHAT) program about a decade ago. Images were obtained at near-ultraviolet, visible, and near-infrared wavelengths using the Advanced Camera for Surveys and the Wide Field Camera 3 aboard Hubble to photograph the northern half of Andromeda.
      This is the largest photomosaic ever made by the Hubble Space Telescope. The target is the vast Andromeda galaxy that is only 2.5 million light-years from Earth, making it the nearest galaxy to our own Milky Way. Andromeda is seen almost edge-on, tilted by 77 degrees relative to Earth’s view. The galaxy is so large that the mosaic is assembled from approximately 600 separate overlapping fields of view taken over 10 years of Hubble observing — a challenge to stitch together over such a large area. The mosaic image is made up of at least 2.5 billion pixels. Hubble resolves an estimated 200 million stars that are hotter than our Sun, but still a fraction of the galaxy’s total estimated stellar population. Interesting regions include: (a) Clusters of bright blue stars embedded within the galaxy, background galaxies seen much farther away, and photo-bombing by a couple bright foreground stars that are actually inside our Milky Way; (b) NGC 206 the most conspicuous star cloud in Andromeda; (c) A young cluster of blue newborn stars; (d) The satellite galaxy M32, that may be the residual core of a galaxy that once collided with Andromeda; (e) Dark dust lanes across myriad stars.
      NASA, ESA, Benjamin F. Williams (UWashington), Zhuo Chen (UWashington), L. Clifton Johnson (Northwestern); Image Processing: Joseph DePasquale (STScI)
      Download this image (2,000 x 1,125)(1.5 MB)


      Download this image (7,680 x 4,320)(16 MB)

      This program was followed up by the Panchromatic Hubble Andromeda Southern Treasury (PHAST), recently published in The Astrophysical Journal and led by Zhuo Chen at the University of Washington, which added images of approximately 100 million stars in the southern half of Andromeda. This region is structurally unique and more sensitive to the galaxy’s merger history than the northern disk mapped by the PHAT survey.
      The combined programs collectively cover the entire disk of Andromeda, which is seen almost edge-on — tilted by 77 degrees relative to Earth’s view. The galaxy is so large that the mosaic is assembled from approximately 600 separate fields of view. The mosaic image is made up of at least 2.5 billion pixels.
      The complementary Hubble survey programs provide information about the age, heavy-element abundance, and stellar masses inside Andromeda. This will allow astronomers to distinguish between competing scenarios where Andromeda merged with one or more galaxies. Hubble’s detailed measurements constrain models of Andromeda’s merger history and disk evolution.
      A Galactic ‘Train Wreck’
      Though the Milky Way and Andromeda formed presumably around the same time many billions of years ago, observational evidence shows that they have very different evolutionary histories, despite growing up in the same cosmological neighborhood. Andromeda seems to be more highly populated with younger stars and unusual features like coherent streams of stars, say researchers. This implies it has a more active recent star-formation and interaction history than the Milky Way.
      “Andromeda’s a train wreck. It looks like it has been through some kind of event that caused it to form a lot of stars and then just shut down,” said Daniel Weisz at the University of California, Berkeley. “This was probably due to a collision with another galaxy in the neighborhood.”
      A possible culprit is the compact satellite galaxy Messier 32, which resembles the stripped-down core of a once-spiral galaxy that may have interacted with Andromeda in the past. Computer simulations suggest that when a close encounter with another galaxy uses up all the available interstellar gas, star formation subsides.
      The Andromeda Galaxy, our closest galactic neighbor, holds over 1 trillion stars and has been a key to unlocking the secrets of the universe. Thanks to NASA’s Hubble Space Telescope, we’re now seeing Andromeda in stunning new detail, revealing its dynamic history and unique structure.
      Credit: NASA’s Goddard Space Flight Center; Lead Producer: Paul Morris
      Download this video

      “Andromeda looks like a transitional type of galaxy that’s between a star-forming spiral and a sort of elliptical galaxy dominated by aging red stars,” said Weisz. “We can tell it’s got this big central bulge of older stars and a star-forming disk that’s not as active as you might expect given the galaxy’s mass.”
      “This detailed look at the resolved stars will help us to piece together the galaxy’s past merger and interaction history,” added Williams.
      Hubble’s new findings will support future observations by NASA’s James Webb Space Telescope and the upcoming Nancy Grace Roman Space Telescope. Essentially a wide-angle version of Hubble (with the same sized mirror), Roman will capture the equivalent of at least 100 high-resolution Hubble images in a single exposure. These observations will complement and extend Hubble’s huge dataset.
      The Hubble Space Telescope has been operating for over three decades and continues to make ground-breaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and mission operations. Lockheed Martin Space, based in Denver, also supports mission operations at Goddard. The Space Telescope Science Institute in Baltimore, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.
      Explore More

      Explore the Night Sky: Messier 31


      Hubble’s High-Definition Panoramic View of the Andromeda Galaxy


      NASA’s Hubble Finds Giant Halo Around the Andromeda Galaxy

      Facebook logo @NASAHubble @NASAHubble Instagram logo @NASAHubble Media Contact:
      Claire Andreoli (claire.andreoli@nasa.gov)
      NASA’s Goddard Space Flight Center, Greenbelt, MD
      Ray Villard
      Space Telescope Science Institute, Baltimore, MD
      Share








      Details
      Last Updated Jan 16, 2025 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center Related Terms
      Andromeda Galaxy Astrophysics Astrophysics Division Galaxies Goddard Space Flight Center Hubble Space Telescope Spiral Galaxies The Universe Keep Exploring Discover More Topics From Hubble
      Hubble Space Telescope


      Since its 1990 launch, the Hubble Space Telescope has changed our fundamental understanding of the universe.


      Hubble Science



      Hubble’s Night Sky Challenge



      Hubble Images


      View the full article
    • By European Space Agency
      The largest photomosaic of the Andromeda galaxy, assembled from NASA/ESA Hubble Space Telescope observations, unveils hundreds of millions of stars. It took more than 10 years to collect data for this colorful portrait of our neighbouring galaxy and was created from more than 600 snapshots. This stunning, colourful mosaic captures the glow of 200 million stars, and is spread across roughly 2.5 billion pixels.
      View the full article
    • By NASA
      This artist’s illustration represents the results from a new study that examines the effects of X-ray and other high-energy radiation unleashed on potential exoplanets from Wolf 359, a nearby red dwarf star. Researchers used Chandra and XMM-Newton to study the impact of steady X-ray and energetic ultraviolet radiation from Wolf 359 on the atmospheres of planets that might be orbiting the star. They found that only a planet with greenhouse gases like carbon dioxide in its atmosphere and at a relatively large distance away from Wolf 359 would have a chance to support life as we know it.X-ray: NASA/CXC/SAO/S.Wolk, et al.; Illustration: NASA/CXC/SAO/M.Weiss; Image processing: NASA/CXC/SAO/N. Wolk Planets around other stars need to be prepared for extreme weather conditions, according to a new study from NASA’s Chandra X-ray Observatory and ESA’s (European Space Agency’s) XMM-Newton that examined the effects of X-rays on potential planets around the most common type of stars.
      Astronomers found that only a planet with greenhouse gases in its atmosphere like Earth and at a relatively large distance away from the star they studied would have a chance to support life as we know it around a nearby star.  
      Wolf 359 is a red dwarf with a mass about a tenth that of the Sun. Red dwarf stars are the most common stars in the universe and live for billions of years, providing ample time for life to develop. At a distance of only 7.8 light-years away, Wolf 359 is also one of the closest stars to the solar system.
      “Wolf 359 can help us unlock the secrets around stars and habitability,” said Scott Wolk of the Center for Astrophysics | Harvard & Smithsonian (CfA), who led the study. “It’s so close and it belongs to such an important class of stars – it’s a great combination.”
      Because red dwarfs are the most prevalent types of stars, astronomers have looked hard to find exoplanets around them. Astronomers have found some evidence for two planets in orbit around Wolf 359 using optical telescopes, but those conclusions have been challenged by other scientists.  
      “While we don’t have proof of planets around Wolf 359 yet, it seems very possible that it hosts multiple planets,” Wolk added. “This makes it an excellent test bed to look at what planets would experience around this kind of star.”
      Wolk and his colleagues used Chandra and XMM to study the amounts of steady X-rays and extreme ultraviolet (UV) radiation – the most energetic type of UV radiation – that Wolf 359 would unleash on the possible planets around it.
      They found that Wolf 359 is producing enough damaging radiation that only a planet with greenhouse gases like carbon dioxide in its atmosphere – and located at a relatively large distance from the star – would likely be able to sustain life.
      “Just being far enough away from the star’s harmful radiation wouldn’t be enough to make it habitable,” said co-author Vinay Kashyap, also of CfA. “A planet around Wolf 359 would also need to be blanketed in greenhouse gases like Earth is.”
      To study the effects of energetic radiation on the habitability of the planet candidates, the team considered the star’s habitable zone – the region around a star where liquid water could exist on a planet’s surface. 
      The outer limit of the habitable zone for Wolf 359 is about 15% of the distance between Earth and the Sun, because the red dwarf is much less bright than the Sun. Neither of the planet candidates for this system is located in Wolf 359’s habitable zone, with one too close to the star and the other too far out.
      “If the inner planet is there, the X-ray and extreme UV radiation it is subjected to would destroy the atmosphere of this planet in only about a million years,” said co-author Ignazio Pillitteri of CfA and the National Institute for Astrophysics in Palermo, Italy.
      The team also considered the effects of radiation on as-yet undetected planets within the habitable zone. They concluded that a planet like the Earth in the middle of the habitable zone should be able to sustain an atmosphere for almost two billion years, while one near the outer edge could last indefinitely, helped by the warming effects of greenhouse gases.
      Another big danger for planets orbiting stars like Wolf 359 is from X-ray flares, or occasional bright bursts of X-rays, on top of the steady, everyday output from the star. Combining observations made with Chandra and XMM-Newton resulted in the discovery of 18 X-ray flares from Wolf 359 over 3.5 days.
      Extrapolating from these observed flares, the team expects that much more powerful and damaging flares would occur over longer periods of time. The combined effects of the steady X-ray and UV radiation and the flares mean that any planet located in the habitable zone is unlikely to have a significant atmosphere long enough for multicellular life, as we know it on Earth, to form and survive. The exception is the habitable zone’s outer edge if the planet has a significant greenhouse effect.
      These results were presented at the 245th meeting of the American Astronomical Society in National Harbor, Maryland, and are being prepared for publication in a journal. NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program. The Smithsonian Astrophysical Observatory’s Chandra X-ray Center controls science operations from Cambridge, Massachusetts, and flight operations from Burlington, Massachusetts.
      Read more from NASA’s Chandra X-ray Observatory.
      Learn more about the Chandra X-ray Observatory and its mission here:
      https://www.nasa.gov/chandra
      https://chandra.si.edu
      News Media Contact
      Megan Watzke
      Chandra X-ray Center
      Cambridge, Mass.
      617-496-7998
      mwatzke@cfa.harvard.edu
      Lane Figueroa
      Marshall Space Flight Center, Huntsville, Alabama
      256-544-0034
      lane.e.figueroa@nasa.gov
      Explore More
      3 min read How It Started, How It’s Going: Johnson Space Center Edition
      Article 23 hours ago 6 min read Ten NASA Science, Tech Instruments Flying to Moon on Firefly Lander
      Article 2 days ago 2 min read NASA, Partners Open Applications for CubeSat Summer Program
      Article 3 days ago View the full article
  • Check out these Videos

×
×
  • Create New...