Jump to content

Hubble Space Telescope Helps Find Evidence that Neptune's Largest Moon Is Warming Up


Recommended Posts

Posted
low_STSCI-H-p-9823-k1340x520.png

Observations obtained by the Hubble telescope and ground-based instruments reveal that Neptune's largest moon, Triton, seems to have heated up significantly since the Voyager spacecraft visited it in 1989.

Even with the warming, no one is likely to plan a summer vacation on Triton, which is a bit smaller than Earth's moon. Since 1989 Triton's temperature has risen from about 37 on the absolute (Kelvin) temperature scale (-392 degrees Fahrenheit) to about 39 Kelvin (-389 degrees Fahrenheit). The scientists are basing a rise in Triton's surface temperature on the Hubble telescope's detection of an increase in the moon's atmospheric pressure, which has at least doubled in bulk since the time of the Voyager encounter. When Triton passed in front of a star known as "Tr180" in the constellation Sagittarius, Hubble measured the star's gradual decrease in brightness. The starlight became fainter as it traveled through Triton's thicker atmosphere, alerting astronomers to changes in the moon's air pressure.

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
      6 min read
      Smarter Searching: NASA AI Makes Science Data Easier to Find
      Image snapshot taken from NASA Worldview of NASA’s Global Precipitation Measurement (GPM) mission on March 15, 2025 showing heavy rain across the southeastern U.S. with an overlay of the GCMD Keyword Recommender for Earth Science, Atmosphere, Precipitation, Droplet Size. NASA Worldview Imagine shopping for a new pair of running shoes online. If each seller described them differently—one calling them “sneakers,” another “trainers,” and someone else “footwear for exercise”—you’d quickly feel lost in a sea of mismatched terminology. Fortunately, most online stores use standardized categories and filters, so you can click through a simple path: Women’s > Shoes > Running Shoes—and quickly find what you need.
      Now, scale that problem to scientific research. Instead of sneakers, think “aerosol optical depth” or “sea surface temperature.” Instead of a handful of retailers, it is thousands of researchers, instruments, and data providers. Without a common language for describing data, finding relevant Earth science datasets would be like trying to locate a needle in a haystack, blindfolded.
      That’s why NASA created the Global Change Master Directory (GCMD), a standardized vocabulary that helps scientists tag their datasets in a consistent and searchable way. But as science evolves, so does the challenge of keeping metadata organized and discoverable. 
      To meet that challenge, NASA’s Office of Data Science and Informatics (ODSI) at the agency’s Marshall Space Flight Center (MSFC) in Huntsville, Alabama, developed the GCMD Keyword Recommender (GKR): a smart tool designed to help data providers and curators assign the right keywords, automatically.
      Smarter Tagging, Accelerated Discovery
      The upgraded GKR model isn’t just a technical improvement; it’s a leap forward in how we organize and access scientific knowledge. By automatically recommending precise, standardized keywords, the model reduces the burden on human curators while ensuring metadata quality remains high. This makes it easier for researchers, students, and the public to find exactly the datasets they need.
      It also sets the stage for broader applications. The techniques used in GKR, like applying focal loss to rare-label classification problems and adapting pre-trained transformers to specialized domains, can benefit fields well beyond Earth science.
      Metadata Matchmaker
      The newly upgraded GKR model tackles a massive challenge in information science known as extreme multi-label classification. That’s a mouthful, but the concept is straightforward: Instead of predicting just one label, the model must choose many, sometimes dozens, from a set of thousands. Each dataset may need to be tagged with multiple, nuanced descriptors pulled from a controlled vocabulary.
      Think of it like trying to identify all the animals in a photograph. If there’s just a dog, it’s easy. But if there’s a dog, a bird, a raccoon hiding behind a bush, and a unicorn that only shows up in 0.1% of your training photos, the task becomes far more difficult. That’s what GKR is up against: tagging complex datasets with precision, even when examples of some keywords are scarce.
      And the problem is only growing. The new version of GKR now considers more than 3,200 keywords, up from about 430 in its earlier iteration. That’s a sevenfold increase in vocabulary complexity, and a major leap in what the model needs to learn and predict.
      To handle this scale, the GKR team didn’t just add more data; they built a more capable model from the ground up. At the heart of the upgrade is INDUS, an advanced language model trained on a staggering 66 billion words drawn from scientific literature across disciplines—Earth science, biological sciences, astronomy, and more.
      NASA ODSI’s GCMD Keyword Recommender AI model automatically tags scientific datasets with the help of INDUS, a large language model trained on NASA scientific publications across the disciplines of astrophysics, biological and physical sciences, Earth science, heliophysics, and planetary science. NASA “We’re at the frontier of cutting-edge artificial intelligence and machine learning for science,” said Sajil Awale, a member of the NASA ODSI AI team at MSFC. “This problem domain is interesting, and challenging, because it’s an extreme classification problem where the model needs to differentiate even very similar keywords/tags based on small variations of context. It’s exciting to see how we have leveraged INDUS to build this GKR model because it is designed and trained for scientific domains. There are opportunities to improve INDUS for future uses.”
      This means that the new GKR isn’t just guessing based on word similarities; it understands the context in which keywords appear. It’s the difference between a model knowing that “precipitation” might relate to weather versus recognizing when it means a climate variable in satellite data.
      And while the older model was trained on only 2,000 metadata records, the new version had access to a much richer dataset of more than 43,000 records from NASA’s Common Metadata Repository. That increased exposure helps the model make more accurate predictions.
      The Common Metadata Repository is the backend behind the following data search and discovery services:
      Earthdata Search International Data Network Learning to Love Rare Words
      One of the biggest hurdles in a task like this is class imbalance. Some keywords appear frequently; others might show up just a handful of times. Traditional machine learning approaches, like cross-entropy loss, which was used initially to train the model, tend to favor the easy, common labels, and neglect the rare ones.
      To solve this, NASA’s team turned to focal loss, a strategy that reduces the model’s attention to obvious examples and shifts focus toward the harder, underrepresented cases. 
      The result? A model that performs better across the board, especially on the keywords that matter most to specialists searching for niche datasets.
      From Metadata to Mission
      Ultimately, science depends not only on collecting data, but on making that data usable and discoverable. The updated GKR tool is a quiet but critical part of that mission. By bringing powerful AI to the task of metadata tagging, it helps ensure that the flood of Earth observation data pouring in from satellites and instruments around the globe doesn’t get lost in translation.
      In a world awash with data, tools like GKR help researchers find the signal in the noise and turn information into insight.
      Beyond powering GKR, the INDUS large language model is also enabling innovation across other NASA SMD projects. For example, INDUS supports the Science Discovery Engine by helping automate metadata curation and improving the relevancy ranking of search results.The diverse applications reflect INDUS’s growing role as a foundational AI capability for SMD.
      The INDUS large language model is funded by the Office of the Chief Science Data Officer within NASA’s Science Mission Directorate at NASA Headquarters in Washington. The Office of the Chief Science Data Officer advances scientific discovery through innovative applications and partnerships in data science, advanced analytics, and artificial intelligence.
      Share








      Details
      Last Updated Jul 09, 2025 Related Terms
      Science & Research Artificial Intelligence (AI) Explore More
      2 min read Polar Tourists Give Positive Reviews to NASA Citizen Science in Antarctica


      Article


      6 hours ago
      2 min read Hubble Observations Give “Missing” Globular Cluster Time to Shine


      Article


      6 days ago
      5 min read How NASA’s SPHEREx Mission Will Share Its All-Sky Map With the World 


      Article


      7 days ago
      Keep Exploring Discover Related Topics
      Missions



      Humans in Space



      Climate Change



      Solar System


      View the full article
    • By NASA
      This illustration shows the parts of a space shuttle orbiter. About the same size and weight as a DC-9 aircraft, the orbiter contains the pressurized crew compartment (which can normally carry up to seven crew members), the cargo bay, and the three main engines mounted on its aft end.NASA This 2001 illustration labels important parts of a space shuttle orbiter. The orbiter was the heart and brains of the space shuttle and served as the crew transport vehicle that carried astronauts to and from space. The space shuttle was comprised of the orbiter, the main engines, the external tank, and the solid rocket boosters. The space shuttle was the world’s first reusable spacecraft and the first spacecraft in history that could carry large satellites both to and from orbit.
      Image credit: NASA
      View the full article
    • By NASA
      As Hubble marks three and a half decades of scientific breakthroughs and technical resilience, the “Hubble at 35 Years” symposium offers a platform to reflect on the mission’s historical, operational, and scientific legacy. Hubble’s trajectory—from early challenges to becoming a symbol of American scientific ingenuity—presents valuable lessons in innovation, collaboration, and crisis response. Bringing together scientists, engineers, and historians at NASA Headquarters ensures that this legacy informs current and future mission planning, including operations for the James Webb Space Telescope, Roman Space Telescope, and other next-generation observatories. The symposium not only honors Hubble’s transformative contributions but also reinforces NASA’s commitment to learning from the past to shape a more effective and ambitious future for space science.
      Hubble at 35 Years
      Lessons Learned in Scientific Discovery and NASA Flagship Mission Operations
      October 16–17, 2025
      James Webb Auditorium, NASA HQ, Washington, D.C.
      The giant Hubble Space Telescope (HST) can be seen as it is suspended in space by Discovery’s Remote Manipulator System (RMS) following the deployment of part of its solar panels and antennae on April 25, 1990.NASA The story of the Hubble Space Telescope confirms its place as the most transformative and significant astronomical observatory in history. Once called “the eighth wonder of the world” by a former NASA administrator, Hubble’s development since its genesis in the early 1970s and its launch, repair, and ultimate impact since 1990 provide ample opportunity to apply insights from its legacy. Scientists and engineers associated with groundbreaking discoveries have always operated within contexts shaped by forces including the government, private industry, the military, and the public at large. The purpose of this symposium is to explore the insights from Hubble’s past and draw connections that can inform the development of mission work today and for the future.
      Contact the Organizer Keep Exploring Discover More Topics From NASA
      Hubble’s 35th Anniversary
      Universe
      Humans In Space
      NASA History

      View the full article
    • By Space Force
      More than 700 Guardians around the world are prepared to participate in a U.S. Space Force led large-scale exercise, Resolute Space 2025, which will demonstrate the Space Force’s preparedness for complex, large-scale military operations.

      View the full article
  • Check out these Videos

×
×
  • Create New...