Jump to content

Discovery Alert: a ‘Hot Neptune’ in a Tight Orbit


Recommended Posts

  • Publishers
Posted
A dark planet, left, is shown in close orbit around its star, right; some of the planet's atmosphere is being blown outward by the star.
Artist’s concept of “hot Neptune” TOI-3261 b.
NASA/JPL-Caltech/K. Miller (Caltech/IPAC)

By Grace Jacobs Corban

The Discovery

A Neptune-sized planet, TOI-3261 b, makes a scorchingly close orbit around its host star. Only the fourth object of its kind ever found, the planet could reveal clues as to how planets such as these form.

Key Facts

An international team of scientists used the NASA space telescope, TESS (the Transiting Exoplanet Survey Satellite), to discover the exoplanet (a planet outside our solar system), then made further observations with ground-based telescopes in Australia, Chile, and South Africa. The measurements placed the new planet squarely in the “hot Neptune desert” – a category of planets with so few members that their scarcity evokes a deserted landscape. This variety of exoplanet is similar to our own Neptune in size and composition, but orbits extremely closely to its star. In this case, a “year” on TOI-3261 b is only 21 hours long. Such a tight orbit earns this planet its place in an exclusive group with, so far, only three other members: ultra-short-period hot Neptunes whose masses have been precisely measured.

Details

Planet TOI-3261 b proves to be an ideal candidate to test new computer models of planet formation. Part of the reason hot Neptunes are so rare is that it is difficult to retain a thick gaseous atmosphere so close to a star. Stars are massive, and so exert a large gravitational force on the things around them, which can strip the layers of gas surrounding a nearby planet. They also emit huge amounts of energy, which blow the gas layers away. Both of these factors mean that hot Neptunes such as TOI-3261 b might have started out as much larger, Jupiter-sized planets, and have since lost a large portion of their mass.

By modeling different starting points and development scenarios, the science team determined that the star and planet system is about 6.5 billion years old, and that the planet started out as a much larger gas giant. It likely lost mass, however, in two ways: photoevaporation, when energy from the star causes gas particles to dissipate, and tidal stripping, when the gravitational force from the star strips layers of gas from the planet. The planet also might have formed farther away from its star, where both of these effects would be less intense, allowing it to retain its atmosphere.

The remaining atmosphere of the planet, one of its most interesting features, will likely invite further atmospheric analysis, perhaps helping to unravel the formation history of this denizen of the “hot Neptune desert.” Planet TOI-3261 b is about twice as dense as Neptune, indicating that the lighter parts of its atmosphere have been stripped away over time, leaving only the heavier components. This shows that the planet must have started out with a variety of different elements in its atmosphere, but at this stage, it is hard to tell exactly what. This mystery could be solved by observing the planet in infrared light, perhaps using NASA’s James Webb Space Telescope – an ideal way to see the identifying fingerprints of the different molecules in the planet’s atmosphere. This will not just help astronomers understand the past of TOI-3261 b, but also begin to uncover the physical processes behind all hot, giant planets.

Fun Facts

The first-ever discovery of an ultra-short-period hot Neptune, LTT-9779 b, came in 2020. Since then, TESS discoveries TOI-849 b and TOI-332 b have also joined the elite ultra-short-period hot-Neptune club (with masses that have been precisely measured). Both LTT-9779 b and TOI-849 b are in the queue for infrared observations with the James Webb Space Telescope, potentially broadening our understanding of these planets’ atmospheres in the coming years.

The Discoverers

An international science team led by astronomer Emma Nabbie of the University of Southern Queensland published their paper on the discovery, “Surviving in the Hot Neptune Desert: The Discovery of the Ultrahot Neptune TOI-3261 b,” in The Astronomical Journal in August 2024.

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 European Space Agency
      Video: 00:01:43 An essential part of ESA’s Space Safety programme is dedicated to getting and keeping Earth’s orbits clean from space debris. In the long run, the Agency aspires to stimulate a true circular economy in space, minimising the impact of spaceflight on Earth and its resources where possible. As part of ESA’s Zero Debris approach, new ESA missions will be designed for safe operations and disposal to stop the creation of new debris by 2030.  
      ESA has now taken another important step on the road towards sustainability in space with its first in-orbit servicing mission RISE, planned for launch in 2029. 
      RISE is a commercial in-orbit servicing mission that will demonstrate that it can safely rendezvous and dock to a geostationary client satellite, extending the life of geostationary satellites that need support with attitude and orbit control, but are otherwise in working order.  
      After verifying that it meets all the performance standards in a first demonstration, prime contractor, operator and co-founder D-Orbit will start commercial life extension services for geostationary satellites. 
      ESA’s RISE mission marks a promising step towards enhancing in-orbit services and technologies, such as refuelling, refurbishment and assembling – all essential elements for creating a circular economy in space.   
      Watch with subtitles
      View the full article
    • By NASA
      6 min read
      NASA, IBM’s ‘Hot’ New AI Model Unlocks Secrets of Sun
      This image from June 20, 2013 shows the bright light of a solar flare and an eruption of solar material shooting through the sun’s atmosphere, called a prominence eruption. Shortly thereafter, this same region of the sun sent a coronal mass ejection out into space — a phenomenon which can cause magnetic storms that degrade communication signals and cause unexpected electrical surges in power grids on Earth. NASA’s new heliophysics AI foundation model, Surya, can help predict these storms. NASA/Goddard/SDO NASA is turning up the heat in solar science with the launch of the Surya Heliophysics Foundational Model, an artificial intelligence (AI) model trained on 14 years of observations from NASA’s Solar Dynamics Observatory. 
      Developed by NASA in partnership with IBM and others, Surya uses advances in AI to analyze vast amounts of solar data, helping scientists better understand solar eruptions and predict space weather that threatens satellites, power grids, and communication systems. The model can be used to provide early warnings to satellite operators and helps scientists predict how the Sun’s ultraviolet output affects Earth’s upper atmosphere.
      Preliminary results show Surya is making strides in solar flare forecasting, a long-standing challenge in heliophysics. Surya, with its ability to generate visual predictions of solar flares two hours into the future, marks a major step towards the use of AI for operational space weather prediction. These initial results surpass existing benchmarks by 15%. By providing open access to the model on HuggingFace and the code on GitHub, NASA encourages the science and applications community to test and explore this AI model for innovative solutions that leverage the unique value of continuous, stable, long-duration datasets from the Solar Dynamics Observatory.
      Illustrations of Solar Dynamics Observatory solar imagery used for training Surya: Solar coronal ultraviolet and extreme ultraviolet images from the Atmospheric Imaging Assembly (AIA) and solar surface velocity and magnetic field maps from the Helioseismic and Magnetic Imager (HMI). NASA/SDO The model’s success builds directly on the Solar Dynamics Observatory’s long-term database. Launched in 2010, NASA’s Solar Dynamics Observatory has provided an unbroken, high-resolution record of the Sun for nearly 15 years through capturing images every 12 seconds in multiple wavelengths, plus precise magnetic field measurements. This stable, well-calibrated dataset, spanning an entire solar cycle, is uniquely suited for training AI models like Surya, enabling them to detect subtle patterns in solar behavior that shorter datasets would miss.
      Surya’s strength lies in its foundation model architecture, which learns directly from raw solar data. Unlike traditional AI systems that require extensive labeling, Surya can adapt quickly to new tasks and applications. Applications include tracking active regions, forecasting flare activity, predicting solar wind speed, and integrating data from other observatories including the joint NASA-ESA Solar and Heliospheric Observatory mission and NASA’s Parker Solar Probe.
      “We are advancing data-driven science by embedding NASA’s deep scientific expertise into cutting-edge AI models,” said Kevin Murphy, chief science data officer at NASA Headquarters in Washington. “By developing a foundation model trained on NASA’s heliophysics data, we’re making it easier to analyze the complexities of the Sun’s behavior with unprecedented speed and precision. This model empowers broader understanding of how solar activity impacts critical systems and technologies that we all rely on here on Earth.”
      These images compare the ground-truth data (right) with model output (center) for solar flares, which are the events behind most space weather. Surya’s prediction is very close to what happened in reality (right). These preliminary results suggest that Surya has learned enough solar physics to predict the structure and evolution of a solar flare by looking at its beginning phase. NASA/SDO/ODSI IMPACT AI Team Solar storms pose significant risks to our technology-dependent society. Powerful solar events energize Earth’s ionosphere, resulting in substantial GPS errors or complete signal loss to satellite communications. They also pose risks to power grids, as geomagnetically induced currents from coronal mass ejections can overload transformers and trigger widespread outages.
      In commercial aviation, solar flares can disrupt radio communications and navigation systems while exposing high-altitude flights to increased radiation. The stakes are even higher for human spaceflight. Astronauts bound for the Moon or Mars may need to depend on precise predictions to shelter from intense radiation during solar particle events.
      The Sun’s influence extends to the growing number of low Earth orbit satellites, including those that deliver global high-speed internet. As solar activity intensifies, it heats Earth’s upper atmosphere, increasing drag that slows satellites, pulls them from orbit, and causes premature reentry. Satellite operators often struggle to forecast where and when solar flares might affect these satellites.
      The “ground truth” solar activity is shown on the top row. The bottom row shows solar activity predicted by Surya. NASA/SDO/ODSI IMPACT AI Team “Our society is built on technologies that are highly susceptible to space weather,” said Joseph Westlake, Heliophysics Division director at NASA Headquarters. “Just as we use meteorology to forecast Earth’s weather, space weather forecasts predict the conditions and events in the space environment that can affect Earth and our technologies. Applying AI to data from our heliophysics missions is a vital step in increasing our space weather defense to protect astronauts and spacecraft, power grids and GPS, and many other systems that power our modern world.”
      While Surya is designed to study the Sun, its architecture and methodology are adaptable across scientific domains. From planetary science to Earth observation, the project lays the foundational infrastructure for similar AI efforts in diverse domains.
      Surya is part of a broader NASA push to develop open-access, AI-powered science tools. Both the model and training datasets are freely available online to researchers, educators, and students worldwide, lowering barriers to participation and sparking new discoveries.
      The process for creating Surya. Foundation models enhance the utility of NASA’s Solar Dynamics Observatory datasets and create a base for building new applications. NASA/ODSI IMPACT AI Team Surya’s training was supported in part by the National Artificial Intelligence Research Resource (NAIRR) Pilot, a National Science Foundation (NSF)-led initiative that provides researchers with access to advanced computing, datasets, and AI tools. The NAIRR Pilot brings together federal and industry resources, such as computing power from NVIDIA, to expand access to the infrastructure needed for cutting-edge AI research.
      “This project shows how the NAIRR Pilot is uniting federal and industry AI resources to accelerate scientific breakthroughs,” said Katie Antypas, director of NSF’s Office of Advanced Cyberinfrastructure. “With support from NVIDIA and NSF, we’re not only enabling today’s research, we’re laying the groundwork for a national AI network to drive tomorrow’s discoveries.”
      Surya is part of a larger effort championed and supported by NASA’s Office of the Chief Science Data Officer and Heliophysics Division, the NSF , and partnering universities to advance NASA’s scientific missions through innovative data science and AI models. Surya’s AI architecture was jointly developed by the Interagency Implementation and Advanced Concepts Team (IMPACT) under the Office of Data Science and Informatics  at NASA’s Marshall Space Flight Center in Huntsville, Alabama; IBM; and a collaborative science team.
      The science team, assembled by NASA Headquarters, consisted of experts from the Southwest Research Institute in San Antonio, Texas; the University of Alabama in Huntsville in Huntsville, Alabama; the University of Colorado Boulder in Boulder, Colorado; Georgia State University in Atlanta, Georgia; Princeton University in Princeton, New Jersey; NASA’s SMD’s Heliophysics Division; NASA’s Goddard Space Flight Center in Greenbelt, Maryland; NASA’s Jet Propulsion Laboratory in Pasadena, California; and the SETI Institute in Mountain View, California.
      For a behind-the-scenes dive into Surya’s architecture, industry and academic collaborations, challenges behind developing the model, read the blog post on NASA’s Science Data Portal:
      https://science.data.nasa.gov/features-events/inside-surya-solar-ai-model
      For more information about NASA’s strategy of developing foundation models for science, visit:
      https://science.nasa.gov/artificial-intelligence-science
      Share








      Details
      Last Updated Aug 20, 2025 Related Terms
      Science & Research Artificial Intelligence (AI) Heliophysics Solar Dynamics Observatory (SDO) The Sun The Sun & Solar Physics Explore More
      3 min read Sun at the Center: Teacher Ambassadors Bring Heliophysics to Classrooms Nationwide


      Article


      20 hours ago
      5 min read NASA-funded Compact Radar Drives Big Changes in Airborne and Suborbital Radar Capabilities


      Article


      23 hours ago
      31 min read Summary of the 2025 GEDI Science Team Meeting


      Article


      2 days ago
      Keep Exploring Discover More Topics From NASA
      Artificial Intelligence for Science


      NASA is creating artificial intelligence tools to help researchers use NASA’s science data more effectively.


      Open Science at NASA


      NASA’s commitment to open science fuels groundbreaking research while maximizing transparency, innovation, and collaboration.


      Humans In Space



      Solar System


      View the full article
    • By NASA
      This artist’s concept shows NASA’s Neil Gehrels Swift Observatory orbiting above Earth.Credit: NASA’s Goddard Space Flight Center/Chris Smith (KBRwyle) To drive the development of key space-based capabilities for the United States, NASA is exploring an opportunity to demonstrate technology to raise a spacecraft’s orbit to a higher altitude. Two American companies – Cambrian Works of Reston, Virginia, and Katalyst Space Technologies of Flagstaff, Arizona – will develop concept design studies for a possible orbit boost for the agency’s Neil Gehrels Swift Observatory.
      Since its launch in 2004, NASA’s Swift mission has led the agency’s fleet of space telescopes in investigating changes in the high-energy universe. The spacecraft’s low Earth orbit has been decaying gradually, which happens to most satellites over time. Because of recent increases in the Sun’s activity, however, Swift is experiencing additional atmospheric drag, speeding up its orbital decay. This lowering orbit presents an opportunity for NASA to advance a U.S. industry capability, while potentially extending the science lifetime of the Swift mission. The concept studies will help determine whether extending Swift’s critical scientific capabilities would be more cost-effective than replacing those capabilities with a new observatory.
      “NASA Science is committed to leveraging commercial technologies to find innovative, cost-effective ways to open new capabilities for the future of the American space sector,” said Nicky Fox, associate administrator, Science Mission Directorate, NASA Headquarters in Washington. “To maintain Swift’s role in our portfolio, NASA Science is uniquely positioned to conduct a rare in-space technology demonstration to raise the satellite’s orbit and solidify American leadership in spacecraft servicing.”
      The concept studies are being developed under Phase III awards through NASA’s Small Business Innovation Research (SBIR) Program, managed by the agency’s Space Technology Mission Directorate, to American small businesses from a pool of existing participants. This approach allows NASA to rapidly explore affordable possibilities to boost Swift on a shorter development timeline than would otherwise be possible, given the rapid rate at which Swift’s orbit is decaying.
      At this time NASA does not have plans for an orbit boost mission and could still allow the spacecraft to reenter Earth’s atmosphere, as many satellites do at the end of their lifetimes. NASA is studying a potential Swift boost to support innovation in the American space industry, while gaining a better understanding of the available options, the technical feasibility, and the risks involved.
      NASA will also work with Starfish Space of Seattle, Washington, to analyze the potential of performing a Swift boost using an asset under development on an existing Phase III SBIR award. Starfish is currently developing the Small Spacecraft Propulsion and Inspection Capability (SSPICY) demonstration for NASA, with the primary objective of inspecting multiple U.S.-owned defunct satellites in low Earth orbit.
      “Our SBIR portfolio exists for circumstances like this – where investments in America’s space industry provide NASA and our partners an opportunity to develop mutually beneficial capabilities,” said Clayton Turner, associate administrator, Space Technology Mission Directorate, NASA Headquarters. “Whether we choose to implement the technologies in this circumstance, understanding how to boost a spacecraft’s orbit could prove valuable for future applications.”
      Swift was designed to observe gamma-ray bursts, the universe’s most powerful explosions, and provide information for other NASA and partner telescopes to follow up on these events. Its fast and flexible observations have been instrumental in advancing how scientists study transient events to understand how the universe works. For more than two decades, Swift has led NASA’s missions in providing new insights on these events, together broadening our understanding of everything from exploding stars, stellar flares, and eruptions in active galaxies, to comets and asteroids in our own solar system and high-energy lightning events on Earth.
      As neutron stars collide, some of the debris blasts away in particle jets moving at nearly the speed of light, producing a brief burst of gamma rays.NASA’s Goddard Space Flight Center/CI Lab “Over its extremely productive lifetime, Swift has been a key player in NASA’s network of space telescopes – directing our fleet to ensure we keep a watchful eye on changes in the universe, both far off and close to home,” said Shawn Domagal-Goldman, acting director, Astrophysics Division, NASA Headquarters. “Now, this long-lived science mission is presenting us with a new opportunity: partnering with U.S. industry to rapidly explore efficient, state-of-the-art solutions that could extend Swift’s transformative work and advance private spacecraft servicing.”
      Cambrian and Katalyst have each been awarded $150,000 under Phase III SBIR contracts for concept design studies. The NASA SBIR program is part of America’s Seed Fund, the nation’s largest source of early-stage, non-dilutive funding for innovative technologies. Through this program, entrepreneurs, startups, and small businesses with less than 500 employees can receive funding and non-monetary support to build, mature, and commercialize their technologies, advancing NASA missions and helping solve important problems facing our country.
      NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the Swift mission in collaboration with Penn State, the Los Alamos National Laboratory in New Mexico, and Northrop Grumman Space Systems in Dulles, Virginia. Other partners include the UK Space Agency, University of Leicester and Mullard Space Science Laboratory in the United Kingdom, Brera Observatory in Italy, and the Italian Space Agency. To learn more about the Swift mission, visit:
      https://www.nasa.gov/swift
      -end-
      Alise Fisher / Jasmine Hopkins
      Headquarters, Washington
      202-358-2546 / 321-432-4624
      alise.m.fisher@nasa.gov / jasmine.s.hopkins@nasa.gov
      View the full article
    • By Amazing Space
      Views Of The Moon From Lunar Orbit
    • By NASA
      This artist’s concept animation shows the orbital dynamics of KOI-134 system which, in 2025, a paper revealed to have two planets: KOI-134 b and KOI-134 c. NASA/JPL-Caltech/K. Miller (Caltech/IPAC) The Planets
      KOI-134 b and KOI-134 c 
      This artist’s concept shows the KOI-134 system which, in 2025, a paper revealed to have two planets: KOI-134 b and KOI-134 c. NASA/JPL-Caltech/K. Miller (Caltech/IPAC) The Discovery
      A new investigation into old Kepler data has revealed that a planetary system once thought to house zero planets actually has two planets which orbit their star in a unique style, like an old-fashioned merry-go-round. 
      Key Facts
      The KOI-134 system contains two planets which orbit their star in a peculiar fashion on two different orbital planes, with one planet exhibiting significant variation in transit times. This is the first-discovered system of its kind. 
      Details 
      Over a decade ago, scientists used NASA’s Kepler Space Telescope to observe the KOI-134 system and thought that it might have a planet orbiting, but they deemed this planet candidate to be a false positive, because its transits (or passes in front of its star) were not lining up as expected. These transits were so abnormal that the planet was actually weeded out through an automated system as a false positive before it could be analyzed further. 
      However, NASA’s commitment to openly sharing scientific data means that researchers can constantly revisit old observations to make new discoveries. In this new study, researchers re-analyzed this Kepler data on KOI-134 and confirmed that not only is the “false positive” actually a real planet, but the system has two planets and some really interesting orbital dynamics! 
      First, the “false positive” planet, named KOI-134 b, was confirmed to be a warm Jupiter (or a warm planet of a similar size to Jupiter). Through this analysis, researchers uncovered that the reason this planet eluded confirmation previously is because it experiences what are called transit timing variations (TTVs), or small differences in a planet’s transit across its star that can make its transit “early” or “late” because the planet is being pushed or pulled by the gravity from another planet which was also revealed in this study. Researchers estimate that KOI-134 b transits across its star as much as 20 hours “late” or “early,” which is a significant variation. In fact, it was so significant that it’s the reason why the planet wasn’t confirmed in initial observations. 
      As these TTVs are caused by the gravitational interaction with another planet, this discovery also revealed a planetary sibling: KOI-134 c. Through studying this system in simulations that include these TTVs, the team found that KOI-134 c is a planet slightly smaller than Saturn and closer to its star than KOI-134 b. 
      This artist’s concept shows the KOI-134 system which, in 2025, a paper revealed to have two planets: KOI-134 b and KOI-134 c. NASA/JPL-Caltech/K. Miller (Caltech/IPAC) KOI-134 c previously eluded observation because it orbits on a tilted orbital plane, a different plane from KOI-134 b, and this tilted orbit prevents the planet from transiting its star. The two orbital planes of these planets are about 15 degrees different from one another, also known as a mutual inclination of 15 degrees, which is significant. Due to the gravitational push and pull between these two planets, their orbital planes also tilt back and forth. 
      Another interesting feature of this planetary system is something called resonance. These two planets have a 2 to 1 resonance, meaning within the same time that one planet completes one orbit, the other completes two orbits. In this case, KOI-134 b has an orbital period (the time it takes a planet to complete one orbit) of about 67 days, which is twice the orbital period of KOI-134 c, which orbits every 33-34 days. 
      Between the separate orbital planes tilting back and forth, the TTVs, and the resonance, the two planets orbit their star in a pattern that resembles two wooden ponies bobbing up and down as they circle around on an old-fashioned merry go round. 
      Fun Facts
      While this system started as a false positive with Kepler, this re-analysis of the data reveals a vibrant system with two planets. In fact, this is the first-ever discovered compact, multiplanetary system that isn’t flat, has such a significant TTV, and experiences orbital planes tilting back and forth. 
      Also, most planetary systems do not have high mutual inclinations between close planet pairs. In addition to being a rarity, mutual inclinations like this are also not often measured because of challenges within the observation process. So, having measurements like this of a significant mutual inclination in a system, as well as measurements of resonance and TTVs, provides a clear picture of dynamics within a planetary system which we are not always able to see. 
      The Discoverers
      A team of scientists led by Emma Nabbie of the University of Southern Queensland published a paper on June 27 on their discovery, “A high mutual inclination system around KOI-134 revealed by transit timing variations,” in the journal “Nature Astronomy.” The observations described in this paper and used in simulations in this paper were made by NASA’s Kepler Space Telescope and the paper included collaboration and contributions from institutions including the University of Geneva, University of La Laguna, Purple Mountain Observatory, the Harvard-Smithsonian Center for Astrophysics, the Georgia Institute of Technology, the University of Southern Queensland, and NASA’s retired Kepler Space Telescope.
      View the full article
  • Check out these Videos

×
×
  • Create New...