Jump to content

Recommended Posts

  • Publishers
Posted
6 Min Read

NASA’s Hubble Finds Kuiper Belt Duo May Be Trio

Illustration of two large, cratered rocks in the foreground right. Another rock is seen in the distance to the left. The black background of space shows the hazy Sun and zodiacal light due to dust in the solar system, as well as scattered distant stars. The words “Artist's Concept” appear in gray at the bottom left.
This artist’s concept depicts one of the possible scenarios for the 148780 Altjira system in the solar system’s Kuiper Belt.
Credits:
NASA, ESA, Joseph Olmsted (STScI)

The puzzle of predicting how three gravitationally bound bodies move in space has challenged mathematicians for centuries, and has most recently been popularized in the novel and television show “3 Body Problem.” There’s no problem, however, with what a team of researchers say is likely a stable trio of icy space rocks in the solar system’s Kuiper Belt, found using data from NASA’s Hubble Space Telescope and the ground-based W. M. Keck Observatory in Hawaii.

If confirmed as the second such three-body system found in the region, the 148780 Altjira system suggests there could be similar triples waiting to be discovered, which would support a particular theory of our solar system’s history and the formation of Kuiper Belt objects (KBOs).

“The universe is filled with a range of three-body systems, including the closest stars to Earth, the Alpha Centauri star system, and we’re finding that the Kuiper Belt may be no exception,” said the study’s lead author Maia Nelsen, a physics and astronomy graduate of Brigham Young University in Provo, Utah.  

Known since 1992, KBOs are primitive icy remnants from the early solar system found beyond the orbit of Neptune. To date, over 3,000 KBOs have been cataloged, and scientists estimate there could be several hundred thousand more that measure over 10 miles in diameter. The largest KBO is dwarf planet Pluto. 

The Hubble finding is crucial support for a KBO formation theory, in which three small rocky bodies would not be the result of collision in a busy Kuiper Belt, but instead form as a trio directly from the gravitational collapse of matter in the disk of material surrounding the newly formed Sun, around 4.5 billion years ago. It’s well known that stars form by gravitational collapse of gas, commonly as pairs or triples, but that idea that cosmic objects like those in the Kuiper Belt form in a similar way is still under investigation.

Illustration of two large, cratered rocks in the foreground right. Another rock is seen in the distance to the left. The black background of space shows the hazy Sun and zodiacal light due to dust in the solar system, as well as scattered distant stars. The words “Artist's Concept” appear in gray at the bottom left.
This artist’s concept depicts one of the possible scenarios for the 148780 Altjira system in the solar system’s Kuiper Belt. It is likely a hierarchical triple formation, in which two very close companions are orbited by a third member at a greater distance. The inner bodies are too close together to be resolved by the Hubble Space Telescope. But Hubble observations of the orbit of the outermost object were used to determine that the central body is not a single spherical object. Other possibilities are that the inner object is a contact binary, where two separate bodies become so close they touch each other. Another idea is that the central body is oddly flat, like a pancake. Of the 40 identified binary objects in the Kuiper Belt, another system, Lempo, has been found to be a triple. The Altjira system is located in the outer reaches of the solar system, 3.7 billion miles away, or 44 times the distance between Earth and the Sun. In this artist’s concept, our Sun is in the constellation Sagittarius, with the Milky Way in the background. The bright red star Antares appears at the top center. Dust in the plane of our solar system glows as zodiacal light.
NASA, ESA, Joseph Olmsted (STScI)

The Altjira system is located in the outer reaches of the solar system, 3.7 billion miles away, or 44 times the distance between Earth and the Sun. Hubble images show two KBOs located about 4,700 miles (7,600 kilometers) apart. However, researchers say that repeated observations of the objects’ unique co-orbital motion indicate the inner object is actually two bodies that are so close together they can’t be distinguished at such a great distance.

“With objects this small and far away, the separation between the two inner members of the system is a fraction of a pixel on Hubble’s camera, so you have to use non-imaging methods to discover that it’s a triple,” said Nelsen.

This takes time and patience, Nelsen explained. Scientists have gathered a 17-year observational baseline of data from Hubble and the Keck Observatory, watching the orbit of the Altjira system’s outer object.

“Over time, we saw the orientation of the outer object’s orbit change, indicating that the inner object was either very elongated or actually two separate objects,” said Darin Ragozzine, also of Brigham Young University, a co-author of the Altjira study.

“A triple system was the best fit when we put the Hubble data into different modeling scenarios,” said Nelsen. “Other possibilities are that the inner object is a contact binary, where two separate bodies become so close they touch each other, or something that actually is oddly flat, like a pancake.”

Currently, there are about 40 identified binary objects in the Kuiper Belt. Now, with two of these systems likely triples, the researchers say it is more likely they are looking not at an oddball, but instead a population of three-body systems, formed by the same circumstances. However, building up that evidence takes time and repeated observations. 

Recent research using data from the Keck Observatory and NASA’s Hubble Space Telescope has revealed a potential three-body system in the Kuiper Belt, known as the Altjira system. This discovery challenges traditional collision theories by suggesting that these triple systems might form directly from the gravitational collapse of material in the early solar disk.
Nasa’s Goddard Space Flight Center; Producer: Paul Morris

The only Kuiper Belt objects that have been explored in detail are Pluto and the smaller object Arrokoth, which NASA’s New Horizons mission visited in 2015 and 2019, respectively. New Horizons showed that Arrokoth is a contact binary, which for KBOs means that two objects that have moved closer and closer to one another are now touching and/or have merged, often resulting in a peanut shape. Ragozzine describes Altjira as a “cousin” of Arrokoth, a member of the same group of Kuiper Belt objects. They estimate Altjira is 10 times larger than Arrokoth, however, at 124 miles (200 kilometers) wide.

While there is no mission planned to fly by Altjira to get Arrokoth-level detail, Nelsen said there is a different upcoming opportunity for further study of the intriguing system. “Altjira has entered an eclipsing season, where the outer body passes in front of the central body. This will last for the next ten years, giving scientists a great opportunity to learn more about it,” Nelsen said. NASA’s James Webb Space Telescope is also joining in on the study of Altjira as it will check if the components look the same in its upcoming Cycle 3 observations

The Hubble study is published in The Planetary Science Journal.

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, Colorado, also supports mission operations at Goddard. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.

Media Contact:

Claire Andreoli (claire.andreoli@nasa.gov)
NASA’s Goddard Space Flight CenterGreenbelt, Maryland

Leah Ramsay
Space Telescope Science Institute, Baltimore, Maryland

Ray Villard
Space Telescope Science Institute, Baltimore, Maryland

Share

Details

Last Updated
Mar 04, 2025
Editor
Andrea Gianopoulos

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
      This NASA/ESA Hubble Space Telescope image features the globular cluster Messier 72 (M72).ESA/Hubble & NASA, A. Sarajedini, G. Piotto, M. Libralato As part of ESA/Hubble’s 35th anniversary celebrations, the European Space Agency (ESA) shared new images that revisited stunning, previously released Hubble targets with the addition of the latest Hubble data and new processing techniques.
      ESA/Hubble released new images of NGC 346, the Sombrero Galaxy, and the Eagle Nebula earlier in the month. Now they are revisiting the star cluster Messier 72 (M72).
      M72 is a collection of stars, formally known as a globular cluster, located in the constellation Aquarius roughly 50,000 light-years from Earth. The intense gravitational attraction between the closely packed stars gives globular clusters their regular, spherical shape. There are roughly 150 known globular clusters associated with the Milky Way galaxy.
      The striking variety in the color of the stars in this image of M72, particularly compared to the original image, results from the addition of ultraviolet observations to the previous visible-light data. The colors indicate groups of different types of stars. Here, blue stars are those that were originally more massive and have reached hotter temperatures after burning through much of their hydrogen fuel; the bright red objects are lower-mass stars that have become red giants. Studying these different groups help astronomers understand how globular clusters, and the galaxies they were born in, initially formed.
      Pierre Méchain, a French astronomer and colleague of Charles Messier, discovered M72 in 1780. It was the first of five star clusters that Méchain would discover while assisting Messier. They recorded the cluster as the 72nd entry in Messier’s famous collection of astronomical objects. It is also one of the most remote clusters in the catalog.
      View the full article
    • By European Space Agency
      The Atomic Clock Ensemble in Space (ACES), ESA’s state-of-the-art timekeeping facility, has been successfully installed on the International Space Station, marking the start of a new chapter in space-based precision science. 
      View the full article
    • By NASA
      Explore Hubble 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 Social Media Media Resources Multimedia Multimedia Images Videos Sonifications Podcasts e-Books Online Activities Lithographs Fact Sheets Posters Hubble on the NASA App Glossary More 35th Anniversary Online Activities 2 min read
      Hubble Visits Glittering Cluster, Capturing Its Ultraviolet Light
      This NASA/ESA Hubble Space Telescope image features the globular cluster Messier 72 (M72). ESA/Hubble & NASA, A. Sarajedini, G. Piotto, M. Libralato As part of ESA/Hubble’s 35th anniversary celebrations, the European Space Agency (ESA) shared new images that revisited stunning, previously released Hubble targets with the addition of the latest Hubble data and new processing techniques.
      ESA/Hubble released new images of NGC 346, the Sombrero Galaxy, and the Eagle Nebula earlier in the month. Now they are revisiting the star cluster Messier 72 (M72).
      M72 is a collection of stars, formally known as a globular cluster, located in the constellation Aquarius roughly 50,000 light-years from Earth. The intense gravitational attraction between the closely packed stars gives globular clusters their regular, spherical shape. There are roughly 150 known globular clusters associated with the Milky Way galaxy.
      The striking variety in the color of the stars in this image of M72, particularly compared to the original image, results from the addition of ultraviolet observations to the previous visible-light data. The colors indicate groups of different types of stars. Here, blue stars are those that were originally more massive and have reached hotter temperatures after burning through much of their hydrogen fuel; the bright red objects are lower-mass stars that have become red giants. Studying these different groups help astronomers understand how globular clusters, and the galaxies they were born in, initially formed.
      Pierre Méchain, a French astronomer and colleague of Charles Messier, discovered M72 in 1780. It was the first of five star clusters that Méchain would discover while assisting Messier. They recorded the cluster as the 72nd entry in Messier’s famous collection of astronomical objects. It is also one of the most remote clusters in the catalog.
      Facebook logo @NASAHubble @NASAHubble Instagram logo @NASAHubble Media Contact:
      Claire Andreoli (claire.andreoli@nasa.gov)
      NASA’s Goddard Space Flight Center, Greenbelt, MD
      Share








      Details
      Last Updated Apr 25, 2025 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center Related Terms
      Hubble Space Telescope Astrophysics Astrophysics Division Globular Clusters Goddard Space Flight Center Star Clusters 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.


      Hubble’s Star Clusters



      Hubble’s 35th Anniversary



      Hubble’s Night Sky Challenge


      View the full article
    • By NASA
      Explore Hubble Science Hubble Space Telescope Eye on Infinity: NASA… 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 Social Media Media Resources Multimedia Multimedia Images Videos Sonifications Podcasts e-Books Online Activities Lithographs Fact Sheets Posters Hubble on the NASA App Glossary More 35th Anniversary Online Activities   5 Min Read Eye on Infinity: NASA Celebrates Hubble’s 35th Year in Orbit
      A selection of photogenic space targets to celebrate the 35th anniversary of NASA’s Hubble Space Telescope. Left to Right: Mars, a small portion of the Rosette Nebula, part of planetary nebula NGC 2899, barred spiral galaxy NGC 5335. Credits:
      NASA, ESA, STScI; Image Processing: Joseph DePasquale (STScI), Alyssa Pagan (STScI) In celebration of the Hubble Space Telescope’s 35 years in Earth orbit, NASA is releasing an assortment of compelling images recently taken by Hubble, stretching from the planet Mars to star-forming regions, and a neighboring galaxy.
      After more than three decades of perusing the universe, Hubble remains a household name — the most well-recognized and scientifically productive telescope in history. The Hubble mission is a glowing success story of America’s technological prowess, unyielding scientific curiosity, and a reiteration of our nation’s pioneering spirit. 
      “Hubble opened a new window to the universe when it launched 35 years ago. Its stunning imagery inspired people across the globe, and the data behind those images revealed surprises about everything from early galaxies to planets in our own solar system,” said Shawn Domagal-Goldman, acting director of the Astrophysics Division at NASA Headquarters in Washington. “The fact that it is still operating today is a testament to the value of our flagship observatories, and provides critical lessons for the Habitable Worlds Observatory, which we plan to be serviceable in the spirit of Hubble.”
      Perched above Earth’s blurry atmosphere, Hubble’s crystal-clear views have been nothing less than transformative for the public’s perception of the cosmos. Through its evocative imagery, Hubble has made astronomy very relevant, engaging, and accessible for people of all ages. Hubble snapshots can portray the universe as awesome, mysterious, and beautiful — and at the same time chaotic, overwhelming, and foreboding.
      A selection of photogenic space targets to celebrate the 35th anniversary of NASA’s Hubble Space Telescope. Upper left: Mars. Upper right: planetary nebula NGC 2899. Lower left: a small portion of the Rosette Nebula. Lower right: barred spiral galaxy NGC 5335. Image: NASA, ESA, STScI; Image Processing: Joseph DePasquale (STScI), Alyssa Pagan (STScI) The 24,000-pound observatory was tucked away inside the space shuttle Discovery’s cargo bay and lofted into low Earth orbit on April 24, 1990. As the shuttle Discovery thundered skyward, the NASA commentator described Hubble as a “new window on the universe.” The telescope turned out to be exactly as promised, and more.
      More scientific papers than ever are based on Hubble data, thanks to the dedication, perseverance, and skills of engineers, scientists, and mission operators. Astronauts chased and rendezvoused with Hubble on five servicing missions in which they upgraded Hubble’s cameras, computers, and other support systems. The servicing missions took place from 1993 to 2009. 
      The telescope’s mission got off to a shaky start in 1990 when an unexpected flaw was found in the observatory’s nearly eight-foot diameter primary mirror. Astronauts gallantly came to the rescue on the first shuttle servicing mission in December 1993 to improve Hubble’s sharpness with corrective optics. 
      To date, Hubble has made nearly 1.7 million observations, looking at approximately 55,000 astronomical targets. Hubble discoveries have resulted in over 22,000 papers and over 1.3 million citations as of February 2025. All the data collected by Hubble is archived and currently adds up to over 400 terabytes, representing the biggest dataset for a NASA astrophysics mission besides the James Webb Space Telescope. 
      Hubble’s long operational life has allowed astronomers to return to the same cosmic scenes multiple times to observe changes that happened during more than three decades: seasonal variability on the planets in our solar system, black hole jets travelling at nearly the speed of light, stellar convulsions, asteroid collisions, expanding supernova bubbles, and much more.
      Hubble’s Senior Project Scientist, Dr. Jennifer Wiseman, takes you on a tour of all four Hubble 35th anniversary images.
      Credit: NASA’s Goddard Space Flight Center; Lead Producer: Paul Morris; Narrator: Dr. Jennifer Wiseman Before 1990, powerful optical telescopes on Earth could see only halfway across the cosmos. Estimates for the age of the universe disagreed by a big margin. Supermassive black holes were only suspected to be the powerhouses behind a rare zoo of energetic phenomena. Not a single planet had been seen around another star.
      Among its long list of breakthroughs: Hubble’s deep field images unveiled myriad galaxies dating back to the early universe. The telescope also allowed scientists to precisely measure the universe’s expansion, find that supermassive black holes are common among galaxies, and make the first measurement of the atmospheres of exoplanets. Hubble also contributed to the discovery of dark energy, the mysterious phenomenon accelerating the expansion of universe, leading to the 2011 Nobel Prize in Physics. 
      The relentless pace of Hubble’s trailblazing discoveries kick-started a new generation of space telescopes for the 21st century. Hubble provided the first observational evidence that there were myriad distant galaxies for Webb to pursue in infrared wavelengths that reach even farther beyond Hubble’s gaze. Now, Hubble and Webb are often being used in complement to study everything from exoplanets to galaxy evolution. 
      Hubble’s planned successor, the Habitable Worlds Observatory, will have a significantly larger mirror than Hubble’s to study the universe in visible and ultraviolet light. It will be significantly sharper than Hubble and up to 100 times more sensitive to starlight. The Habitable Worlds Observatory will advance science across all of astrophysics, as Hubble has done for over three decades. A major goal of the future mission is to identify terrestrial planets around neighboring stars that might be habitable.
      The Hubble Space Telescope 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.

      Lee esta historia en español aquí

      Facebook logo @NASAHubble @NASAHubble Instagram logo @NASAHubble Related Images & Videos
      Mosaic of Hubble 35th Anniversary Targets
      A selection of photogenic space targets to celebrate the 35th anniversary of NASA’s Hubble Space Telescope. Upper left: Mars. Upper right: planetary nebula NGC 2899. Lower left: a small portion of the Rosette Nebula. Lower right: barred spiral galaxy NGC 5335.


      Mars Near Opposition 2024
      This is a combination of Hubble Space Telescope images of Mars taken from December 28th to 30th, 2024. Mars was approximately 61 million miles from Earth. Thin water-ice clouds that are apparent in ultraviolet light give the Red Planet a frosty appearance.


      Planetary Nebula NGC 2899
      This Hubble Space Telescope image captures the beauty of the moth-like planetary nebula NGC 2899. This object has a diagonal, bipolar, cylindrical outflow of gas propelled by radiation and stellar winds. The colors are from glowing hydrogen and oxygen.


      Dark Clouds in Rosette Nebula
      This is a Hubble Space Telescope photo of a small portion of the Rosette Nebula, a huge star-forming region spanning 100 light-years across and located 5,200 light-years away. Dark clouds of hydrogen gas laced with dust are silhouetted across the image.


      Rosette Nebula Context Image
      The Rosette Nebula is a vast star-forming region, 100 light-years across, that lies at one end of a giant molecular cloud. The background image is from the Digitized Sky Survey, while the inset is a small portion of the nebula as photographed by the Hubble Space Telescope.


      NGC 5335
      NASA’s Hubble Space Telescope captured in exquisite detail a face-on view of a remarkable-looking galaxy. NGC 5335 is categorized as a flocculent spiral galaxy with patchy streamers of star formation across its disk.


      Mars Near Opposition Compass Image
      These two images of Mars and its moon Phobos were captured by the Hubble Space Telescope’s Wide Field Camera 3 (WFC3) on consecutive days in December 2024. Compass arrows and a color key are provided for reference.


      Planetary Nebula NGC 2899 Compass Image
      This image of planetary nebula NGC 2899 was captured by the Hubble Space Telescope’s Wide Field Camera 3 (WFC3). The image shows a scale bar, compass arrows, and color key for reference.


      Dark Clouds in Rosette Nebula Compass Image
      This image of dark clouds in the Rosette Nebula was captured by the Hubble Space Telescope’s Wide Field Camera 3 (WFC3). The image shows a scale bar, compass arrows, and color key for reference.


      NGC 5335 Compass Image
      This image of barred spiral galaxy NGC 5335 was captured by the Hubble Space Telescope’s Wide Field Camera 3 (WFC3). The image shows a scale bar, compass arrows, and color key for reference.


      Mars Rotation
      This animation was assembled from a combination of Hubble Space Telescope images of Mars taken from December 28th to 30th, 2024. At the midpoint of the Hubble observations, Mars was approximately 61 million miles from Earth. The photos were then mapped onto a sphere, which is the…


      Planetary Nebula NGC 2899
      This video zooms across 6,500 light-years through a star-studding field to visit the planetary nebula NGC 2899, as photographed by the Hubble Space Telescope. The nebula has a diagonal bipolar structure formed by a cylindrical-shaped outflow of hot gasses and radiation from the c…


      Rosette Nebula
      This video offers a close-up look at a small portion of the magnificent Rosette Nebula, as photographed by the Hubble Space Telescope. Though Hubble cannot take three-dimensional pictures, this video is a visualization treatment of the photo to give a sense of depth with foregrou…




      Share








      Details
      Last Updated Apr 23, 2025 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center Contact Media Claire Andreoli
      NASA’s Goddard Space Flight Center
      Greenbelt, Maryland
      claire.andreoli@nasa.gov
      Ray Villard
      Space Telescope Science Institute
      Baltimore, Maryland
      Related Terms
      Hubble Space Telescope Astrophysics Astrophysics Division Galaxies Goddard Space Flight Center Mars Nebulae Planetary Nebulae Planetary Science Planets Spiral Galaxies Stars The Solar System The Universe
      Additional Links
      Hubble’s 35th Anniversary page
      NASA Ciencia: Con la mirada en el infinito: La NASA celebra 35 años de la puesta en órbita del telescopio Hubble
      ESA Hubble’s Story


      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 Highlights



      Hubble’s 35th Anniversary



      Hubble Images


      View the full article
    • By European Space Agency
      In celebration of the NASA/ESA Hubble Space Telescope’s 35 years in Earth orbit, an assortment of images that were recently taken by Hubble has been released today. This stretches from the planet Mars to images of stellar birth and death, and a magnificent neighbouring galaxy. After over three decades of scrutinising our Universe, Hubble remains a household word as the most well-recognised telescope in scientific history.
      View the full article
  • Check out these Videos

×
×
  • Create New...