Jump to content

Recommended Posts

Posted
low_STScI-J-p2023a-d-1280x720.png

Brown dwarfs, often called “failed stars,” weigh up to 80 times as much as Jupiter, yet their gravity compacts them to about the size of Jupiter in diameter. And like Jupiter, brown dwarfs can have clouds and weather. Astronomers have found evidence that the closest known brown dwarf, Luhman 16A, has Jupiter-like cloud bands. In contrast its companion brown dwarf, Luhman 16B, shows signs of patchy clouds.

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
      3 min read
      NASA’s Cloud-based Confluence Software Helps Hydrologists Study Rivers on a Global Scale
      The Paraná River in northern Argentina. Confluence, which is open-source and free to use, allows researchers to estimate river discharge and suspended sediment levels in Earth’s rivers at a global scale. NASA/ISS Rivers and streams wrap around Earth in complex networks millions of miles long, driving trade, nurturing ecosystems, and stocking critical reserves of freshwater.
      But the hydrologists who dedicate their professional lives to studying this immense web of waterways do so with a relatively limited set of tools. Around the world, a patchwork of just 3,000 or so river gauge stations supply regular, reliable data, making it difficult for hydrologists to detect global trends.
      “The best way to study a river,” said Colin Gleason, Armstrong Professional Development Professor of Civil and Environmental Engineering at the University of Massachusetts, Amherst, “is to get your feet wet and visit it yourself. The second best way to study a river is to use a river gauge.”
      Now, thanks to Gleason and a team of more than 30 researchers, there’s another option: ‘Confluence,’ an analytic collaborative framework that leverages data from NASA’s Surface Water and Ocean Topography (SWOT) mission and the Harmonized Landsat Sentinel-2 archive (HLS) to estimate  river discharge and suspended sediment levels in every river on Earth wider than 50 meters. NASA’s Physical Oceanography Distributed Active Archive Center (PO.DAAC) hosts the software, making it open-source and free for users around the world.
      By incorporating both altimetry data from SWOT which informs discharge estimates, and optical data from HLS, which informs estimates of suspended sediment data, Confluence marks the first time hydrologists can create timely models of river size and water quality at a global scale. Compared to existing workflows for estimating suspended sediment using HLS data, Confluence is faster by a factor of 30.
      I can’t do global satellite hydrology without this system. Or, I could, but it would be extremely time consuming and expensive.
      Colin Gleason

      Nikki Tebaldi, a Cloud Adoption Engineer at NASA’s Jet Propulsion Laboratory (JPL) and Co-Investigator for Confluence, was the lead developer on this project. She said that while the individual components of Confluence have been around for decades, bringing them together within a single, cloud-based processing pipeline was a significant challenge.
      “I’m really proud that we’ve pieced together all of these different algorithms, got them into the cloud, and we have them all executing commands and working,” said Tebaldi.
      Suresh Vannan, former manager of PO.DAAC and a Co-Investigator for Confluence, said this new ability to produce timely, global estimates of river discharge and quality will have a huge impact on hydrological models assessing everything from the health of river ecosystems to snowmelt.
      “There are a bunch of science applications that river discharge can be used for, because it’s pretty much taking a snapshot of what the river looks like, how it behaves. Producing that snapshot on a global scale is a game changer,” said Vannan.
      While the Confluence team is still working with PO.DAAC to complete their software package, users can currently access the Confluence source code here. For tutorials, manuals, and other user guides, visit the PO.DAAC webpage here.
      All of these improvements to the original Confluence algorithms developed for SWOT were made possible by NASA’s Advanced Intelligent Systems Technology (AIST) program, a part of the agency’s Earth Science Technology Office (ESTO), in collaboration with SWOT and PO.DAAC.
      To learn more about opportunities to develop next-generation technologies for studying Earth from outer space, visit ESTO’s solicitation page here.
      Project Lead: Colin Gleason / University of Massachusetts, Amherst
      Sponsoring Organization: Advanced Intelligent Systems Technology program, within NASA’s Earth Science Technology Office
      Share








      Details
      Last Updated Feb 04, 2025 Related Terms
      Science-enabling Technology Earth Science Oceanography SWOT (Surface Water and Ocean Topography) Explore More
      15 min read Summary of the 53rd U.S.–Japan ASTER Science Team Meeting


      Article


      2 weeks ago
      23 min read Summary of the 2024 Quadrennial Ozone Symposium


      Article


      2 weeks ago
      2 min read An Introduction to NASA Citizen Science for Service Members, Veterans and their Families


      Article


      2 weeks ago
      View the full article
    • By NASA
      3 Min Read NASA Scientists Find New Human-Caused Shifts in Global Water Cycle
      Cracked mud and salt on the valley floor in Death Valley National Park in California can become a reflective pool after rains. (File photo) Credits: NPS/Kurt Moses In a recently published paper, NASA scientists use nearly 20 years of observations to show that the global water cycle is shifting in unprecedented ways. The majority of those shifts are driven by activities such as agriculture and could have impacts on ecosystems and water management, especially in certain regions.
      “We established with data assimilation that human intervention in the global water cycle is more significant than we thought,” said Sujay Kumar, a research scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and a co-author of the paper published in the Proceedings of the National Academy of Sciences.
      The shifts have implications for people all over the world. Water management practices, such as designing infrastructure for floods or developing drought indicators for early warning systems, are often based on assumptions that the water cycle fluctuates only within a certain range, said Wanshu Nie, a research scientist at NASA Goddard and lead author of the paper.
      “This may no longer hold true for some regions,” Nie said. “We hope that this research will serve as a guide map for improving how we assess water resources variability and plan for sustainable resource management, especially in areas where these changes are most significant.”
      One example of the human impacts on the water cycle is in North China, which is experiencing an ongoing drought. But vegetation in many areas continues to thrive, partially because producers continue to irrigate their land by pumping more water from groundwater storage, Kumar said. Such interrelated human interventions often lead to complex effects on other water cycle variables, such as evapotranspiration and runoff.
      Nie and her colleagues focused on three different kinds of shifts or changes in the cycle: first, a trend, such as a decrease in water in a groundwater reservoir; second, a shift in seasonality, like the typical growing season starting earlier in the year, or an earlier snowmelt; and third a change in extreme events, like “100-year floods” happening more frequently.
      The scientists gathered remote sensing data from 2003 to 2020 from several different NASA satellite sources: the Global Precipitation Measurement mission satellite for precipitation data, a soil moisture dataset from the European Space Agency’s Climate Change Initiative, and the Gravity Recovery and Climate Experiment satellites for terrestrial water storage data. They also used products from the Moderate Resolution Imaging Spectroradiometer satellite instrument to provide information on vegetation health.
      “This paper combines several years of our team’s effort in developing capabilities on satellite data analysis, allowing us to precisely simulate continental water fluxes and storages across the planet,” said Augusto Getirana, a research scientist at NASA Goddard and a co-author of the paper.
      The study results suggest that Earth system models used to simulate the future global water cycle should evolve to integrate the ongoing effects of human activities. With more data and improved models, producers and water resource managers could understand and effectively plan for what the “new normal” of their local water situation looks like, Nie said.
      By Erica McNamee
      NASA’s Goddard Space Flight Center, Greenbelt, Maryland
      Share
      Details
      Last Updated Jan 16, 2025 EditorKate D. RamsayerContactKate D. Ramsayerkate.d.ramsayer@nasa.gov Related Terms
      Earth Global Precipitation Measurement (GPM) Goddard Space Flight Center Moderate Resolution Imaging Spectroradiometer (MODIS) Water & Energy Cycle Explore More
      4 min read NASA’s Global Precipitation Measurement Mission: 10 years, 10 stories
      From peering into hurricanes to tracking El Niño-related floods and droughts to aiding in disaster…
      Article 11 months ago 4 min read NASA Satellites Find Snow Didn’t Offset Southwest US Groundwater Loss
      Article 7 months ago 4 min read NASA Satellites Reveal Abrupt Drop in Global Freshwater Levels
      Earth’s total amount of freshwater dropped abruptly starting in May 2014 and has remained low…
      Article 2 months ago View the full article
    • By NASA
      International teams of astronomers monitoring a supermassive black hole in the heart of a distant galaxy have detected features never seen before using data from NASA missions and other facilities. The features include the launch of a plasma jet moving at nearly one-third the speed of light and unusual, rapid X-ray fluctuations likely arising from near the very edge of the black hole.
      Radio images of 1ES 1927+654 reveal emerging structures that appear to be jets of plasma erupting from both sides of the galaxy’s central black hole following a strong radio flare. The first image, taken in June 2023, shows no sign of the jet, possibly because hot gas screened it from view. Then, starting in February 2024, the features emerge and expand away from the galaxy’s center, covering a total distance of about half a light-year as measured from the center of each structure. NSF/AUI/NSF NRAO/Meyer at al. 2025 The source is 1ES 1927+654, a galaxy located about 270 million light-years away in the constellation Draco. It harbors a central black hole with a mass equivalent to about 1.4 million Suns.
      “In 2018, the black hole began changing its properties right before our eyes, with a major optical, ultraviolet, and X-ray outburst,” said Eileen Meyer, an associate professor at UMBC (University of Maryland Baltimore County). “Many teams have been keeping a close eye on it ever since.”
      She presented her team’s findings at the 245th meeting of the American Astronomical Society in National Harbor, Maryland. A paper led by Meyer describing the radio results was published Jan. 13 in The Astrophysical Journal Letters.
      After the outburst, the black hole appeared to return to a quiet state, with a lull in activity for nearly a year. But by April 2023, a team led by Sibasish Laha at UMBC and NASA’s Goddard Space Flight Center in Greenbelt, Maryland, had noted a steady, months-long increase in low-energy X-rays in measurements by NASA’s Neil Gehrels Swift Observatory and NICER (Neutron star Interior Composition Explorer) telescope on the International Space Station. This monitoring program, which also includes observations from NASA’s NuSTAR (Nuclear Spectroscopic Telescope Array) and ESA’s (European Space Agency) XMM-Newton mission, continues.
      The increase in X-rays triggered the UMBC team to make new radio observations, which indicated a strong and highly unusual radio flare was underway. The scientists then began intensive observations using the NRAO’s (National Radio Astronomy Observatory) VLBA (Very Long Baseline Array) and other facilities. The VLBA, a network of radio telescopes spread across the U.S., combines signals from individual dishes to create what amounts to a powerful, high-resolution radio camera. This allows the VLBA to detect features less than a light-year across at 1ES 1927+654’s distance.
      Active galaxy 1ES 1927+654, circled, has exhibited extraordinary changes since 2018, when a major outburst occurred in visible, ultraviolet, and X-ray light. The galaxy harbors a central black hole weighing about 1.4 million solar masses and is located 270 million light-years away. Pan-STARRS Radio data from February, April, and May 2024 reveals what appear to be jets of ionized gas, or plasma, extending from either side of the black hole, with a total size of about half a light-year. Astronomers have long puzzled over why only a fraction of monster black holes produce powerful plasma jets, and these observations may provide critical clues.
      “The launch of a black hole jet has never been observed before in real time,” Meyer noted. “We think the outflow began earlier, when the X-rays increased prior to the radio flare, and the jet was screened from our view by hot gas until it broke out early last year.”
      A paper exploring that possibility, led by Laha, is under review at The Astrophysical Journal. Both Meyer and Megan Masterson, a doctoral candidate at the Massachusetts Institute of Technology in Cambridge who also presented at the meeting, are co-authors.
      Using XMM-Newton observations, Masterson found that the black hole exhibited extremely rapid X-ray variations between July 2022 and March 2024. During this period, the X-ray brightness repeatedly rose and fell by 10% every few minutes. Such changes, called millihertz quasiperiodic oscillations, are difficult to detect around supermassive black holes and have been observed in only a handful of systems to date. 
      “One way to produce these oscillations is with an object orbiting within the black hole’s accretion disk. In this scenario, each rise and fall of the X-rays represents one orbital cycle,” Masterson said.  
      If the fluctuations were caused by an orbiting mass, then the period would shorten as the object fell ever closer to the black hole’s event horizon, the point of no return. Orbiting masses generate ripples in space-time called gravitational waves. These waves drain away orbital energy, bringing the object closer to the black hole, increasing its speed, and shortening its orbital period.
      Over two years, the fluctuation period dropped from 18 minutes to just 7 — the first-ever measurement of its kind around a supermassive black hole. If this represented an orbiting object, it was now moving at half the speed of light. Then something unexpected happened — the fluctuation period stabilized.
      In this artist’s concept, matter is stripped from a white dwarf (sphere at lower right) orbiting within the innermost accretion disk surrounding 1ES 1927+654’s supermassive black hole. Astronomers developed this scenario to explain the evolution of rapid X-ray oscillations detected by ESA’s (European Space Agency) XMM-Newton satellite. ESA’s LISA (Laser Interferometer Space Antenna) mission, due to launch in the next decade, should be able to confirm the presence of an orbiting white dwarf by detecting the gravitational waves it produces. NASA/Aurore Simonnet, Sonoma State University “We were shocked by this at first,” Masterson explained. “But we realized that as the object moved closer to the black hole, its strong gravitational pull could begin to strip matter from the companion. This mass loss could offset the energy removed by gravitational waves, halting the companion’s inward motion.”
      So what could this companion be? A small black hole would plunge straight in, and a normal star would quickly be torn apart by the tidal forces near the monster black hole. But the team found that a low-mass white dwarf — a stellar remnant about as large as Earth — could remain intact close to the black hole’s event horizon while shedding some of its matter. A paper led by Masterson summarizing these results will appear in the Feb. 13 edition of the journal Nature.
      This model makes a key prediction, Masterson notes. If the black hole does have a white dwarf companion, the gravitational waves it produces will be detectable by LISA (Laser Interferometer Space Antenna), an ESA mission in partnership with NASA that is expected to launch in the next decade.

      Download high-resolution images from NASA’s Scientific Visualization Studio

      By Francis Reddy
      NASA’s Goddard Space Flight Center, Greenbelt, Md.
      Media Contacts:
      Claire Andreoli
      301-286-1940
      claire.andreoli@nasa.gov
      NASA’s Goddard Space Flight Center, Greenbelt, Md.
      Jill Malusky
      304-456-2236
      jmalusky@nrao.edu
      National Radio Astronomy Observatory, Charlottesville, Va.
      Facebook logo @NASAUniverse @NASAUniverse Instagram logo @NASAUniverse Share








      Details
      Last Updated Jan 13, 2025 Related Terms
      Active Galaxies Astrophysics Black Holes Galaxies, Stars, & Black Holes Goddard Space Flight Center Jet Propulsion Laboratory Neil Gehrels Swift Observatory NICER (Neutron star Interior Composition Explorer) NuSTAR (Nuclear Spectroscopic Telescope Array) Radio Astronomy Supermassive Black Holes The Universe White Dwarfs X-ray Astronomy XMM-Newton (X-ray Multi-Mirror Newton) View the full article
    • By USH
      A video taken by an airline passenger reportedly during a commercial flight over the UK shows what seem to be two figures standing on a layer of clouds. 

      The intriguing footage has sparked a wave of speculation online. While some viewers suggest the figures could be supernatural beings, closer analysis of the footage reveals additional shapes emerging through the clouds as the camera pans from left to right, image below.

      This has led others to theorize that the "figures" might actually be exhaust stacks or other tall structures releasing steam, breaking through a fog layer and creating an illusion of human-like forms. 
      Rather than supernatural entities, the phenomenon is more likely an example of pareidolia, a psychological tendency to perceive familiar shapes, such as faces or figures, in random patterns.
        View the full article
    • By NASA
      5 Min Read NASA’s Parker Solar Probe Makes History With Closest Pass to Sun
      An artist’s concept showing Parker Solar Probe. Credits:
      NASA/APL Operations teams have confirmed NASA’s mission to “touch” the Sun survived its record-breaking closest approach to the solar surface on Dec. 24, 2024.
      Breaking its previous record by flying just 3.8 million miles above the surface of the Sun, NASA’s Parker Solar Probe hurtled through the solar atmosphere at a blazing 430,000 miles per hour — faster than any human-made object has ever moved. A beacon tone received late on Dec. 26 confirmed the spacecraft had made it through the encounter safely and is operating normally.
      This pass, the first of more to come at this distance, allows the spacecraft to conduct unrivaled scientific measurements with the potential to change our understanding of the Sun.
      Flying this close to the Sun is a historic moment in humanity’s first mission to a star.
      Nicky fox
      NASA Associate Administrator, Science Mission Directorate
      “Flying this close to the Sun is a historic moment in humanity’s first mission to a star,” said Nicky Fox, who leads the Science Mission Directorate at NASA Headquarters in Washington. “By studying the Sun up close, we can better understand its impacts throughout our solar system, including on the technology we use daily on Earth and in space, as well as learn about the workings of stars across the universe to aid in our search for habitable worlds beyond our home planet.”
      NASA’s Parker Solar Probe survived its record-breaking closest approach to the solar surface on Dec. 24, 2024. Breaking its previous record by flying just 3.8 million miles above the surface of the Sun, the spacecraft hurtled through the solar atmosphere at a blazing 430,000 miles per hour — faster than any human-made object has ever moved.
      Credits: NASA This video can be freely shared and downloaded at https://svs.gsfc.nasa.gov/14741.
      Parker Solar Probe has spent the last six years setting up for this moment. Launched in 2018, the spacecraft used seven flybys of Venus to gravitationally direct it ever closer to the Sun. With its last Venus flyby on Nov. 6, 2024, the spacecraft reached its optimal orbit. This oval-shaped orbit brings the spacecraft an ideal distance from the Sun every three months — close enough to study our Sun’s mysterious processes but not too close to become overwhelmed by the Sun’s heat and damaging radiation. The spacecraft will remain in this orbit for the remainder of its primary mission.
      “Parker Solar Probe is braving one of the most extreme environments in space and exceeding all expectations,” said Nour Rawafi, the project scientist for Parker Solar Probe at the Johns Hopkins Applied Physics Laboratory (APL), which designed, built, and operates the spacecraft from its campus in Laurel, Maryland. “This mission is ushering a new golden era of space exploration, bringing us closer than ever to unlocking the Sun’s deepest and most enduring mysteries.”
      Close to the Sun, the spacecraft relies on a carbon foam shield to protect it from the extreme heat in the upper solar atmosphere called the corona, which can exceed 1 million degrees Fahrenheit. The shield was designed to reach temperatures of 2,600 degrees Fahrenheit — hot enough to melt steel — while keeping the instruments behind it shaded at a comfortable room temperature. In the hot but low-density corona, the spacecraft’s shield is expected to warm to 1,800 degrees Fahrenheit.
      The spacecraft’s record close distance of 3.8 million miles may sound far, but on cosmic scales it’s incredibly close. If the solar system was scaled down with the distance between the Sun and Earth the length of a football field, Parker Solar Probe would be just four yards from the end zone — close enough to pass within the tenuous outer atmosphere of the Sun known as the corona. NASA/APL “It’s monumental to be able to get a spacecraft this close to the Sun,” said John Wirzburger, the Parker Solar Probe mission systems engineer at APL. “This is a challenge the space science community has wanted to tackle since 1958 and had spent decades advancing the technology to make it possible.”
      By flying through the solar corona, Parker Solar Probe can take measurements that help scientists better understand how the region gets so hot, trace the origin of the solar wind (a constant flow of material escaping the Sun), and discover how energetic particles are accelerated to half the speed of light.
      “The data is so important for the science community because it gives us another vantage point,” said Kelly Korreck, a program scientist at NASA Headquarters and heliophysicist who worked on one of the mission’s instruments. “By getting firsthand accounts of what’s happening in the solar atmosphere, Parker Solar Probe has revolutionized our understanding of the Sun.”
      Previous passes have already aided scientists’ understanding of the Sun. When the spacecraft first passed into the solar atmosphere in 2021, it found the outer boundary of the corona is wrinkled with spikes and valleys, contrary to what was expected. Parker Solar Probe also pinpointed the origin of important zig-zag-shaped structures in the solar wind, called switchbacks, at the visible surface of the Sun — the photosphere.
      Since that initial pass into the Sun, the spacecraft has been spending more time in the corona, where most of the critical physical processes occur.
      This conceptual image shows Parker Solar Probe about to enter the solar corona. NASA/Johns Hopkins APL/Ben Smith “We now understand the solar wind and its acceleration away from the Sun,” said Adam Szabo, the Parker Solar Probe mission scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “This close approach will give us more data to understand how it’s accelerated closer in.”
      Parker Solar Probe has also made discoveries across the inner solar system. Observations showed how giant solar explosions called coronal mass ejections vacuum up dust as they sweep across the solar system, and other observations revealed unexpected findings about solar energetic particles. Flybys of Venus have documented the planet’s natural radio emissions from its atmosphere, as well as the first complete image of its orbital dust ring.
      So far, the spacecraft has only transmitted that it’s safe, but soon it will be in a location that will allow it to downlink the data it collected on this latest solar pass.
      The data that will come down from the spacecraft will be fresh information about a place that we, as humanity, have never been.
      Joe Westlake
      Heliophysics Division Director, NASA Headquarters
      “The data that will come down from the spacecraft will be fresh information about a place that we, as humanity, have never been,” said Joe Westlake, the director of the Heliophysics Division at NASA Headquarters. “It’s an amazing accomplishment.”
      The spacecraft’s next planned close solar passes come on March 22, 2025, and June 19, 2025.
      By Mara Johnson-Groh
      NASA’s Goddard Space Flight Center, Greenbelt, Md.
      Media Contact: Sarah Frazier
      Share








      Details
      Last Updated Dec 27, 2024 Editor Abbey Interrante Related Terms
      Goddard Space Flight Center Heliophysics Heliophysics Division Parker Solar Probe (PSP) Science & Research Science Mission Directorate Solar Flares Solar Wind Space Weather The Sun The Sun & Solar Physics Explore More
      1 min read NASA’s Parker Solar Probe Touches The Sun For The First Time


      Article


      3 years ago
      4 min read Final Venus Flyby for NASA’s Parker Solar Probe Queues Closest Sun Pass


      Article


      2 months ago
      6 min read 10 Things to Know About Parker Solar Probe
      On Aug. 12, 2018, NASA launched Parker Solar Probe to the Sun, where it will…


      Article


      6 years ago
      Keep Exploring Discover More Topics From NASA
      Missions



      Humans in Space



      Climate Change



      Solar System


      View the full article
  • Similar Videos

  • Check out these Videos

×
×
  • Create New...