Jump to content

Recommended Posts

Posted
low_keystone.png

A team of astronomers led by the University of Arizona has directly imaged with the SPHERE instrument on ESO's Very Large Telescope the first planet ever found in a wide orbit inside a triple-star system. The orbit of such a planet had been expected to be unstable, probably resulting in the planet being quickly ejected from the system. But somehow this one survives. This observation of the HD 131399 system suggests that such systems may actually be more common than previously thought. The results will be published online in the journal Science on July 7, 2016. The artist's impression shows a view of the triple-star system HD 131399 from the giant planet orbiting the system. The planet is HD 131399Ab and appears at the lower left of the picture.

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
      In about 5 billion years, our Sun will run out of fuel and expand, possibly engulfing Earth. These end stages of a star’s life can be utterly beautiful – as is the case with this planetary nebula called the Helix Nebula. Astronomers study these objects by looking at all kinds of light.X-ray: NASA/CXC/SAO/Univ Mexico/S. Estrada-Dorado et al.; Ultraviolet: NASA/JPL; Optical: NASA/ESA/STScI (M. Meixner)/NRAO (T.A. Rector); Infrared: ESO/VISTA/J. Emerson; Image Processing: NASA/CXC/SAO/K. Arcand This image of the Helix Nebula, released on March 4, 2025, shows a potentially destructive white dwarf at the nebula’s center: this star may have destroyed a planet. This has never been seen before – and could explain a mysterious X-ray signal that astronomers have detected from the nebula for over 40 years.
      This view combines X-rays from NASA’s Chandra X-ray Observatory (magenta), optical light data from NASA’s Hubble Space Telescope (orange, light blue), infrared data from the European Southern Observatory VISTA telescope (gold, dark blue), and ultraviolet data from GALEX (purple) of the Helix Nebula. Data from Chandra indicates that this white dwarf has destroyed a very closely orbiting planet.
      Image credit: X-ray: NASA/CXC/SAO/Univ Mexico/S. Estrada-Dorado et al.; Ultraviolet: NASA/JPL; Optical: NASA/ESA/STScI (M. Meixner)/NRAO (T.A. Rector); Infrared: ESO/VISTA/J. Emerson; Image Processing: NASA/CXC/SAO/K. Arcand
      View the full article
    • By NASA
      4 min read
      NASA to Launch Three Rockets from Alaska in Single Aurora Experiment
      Three NASA-funded rockets are set to launch from Poker Flat Research Range in Fairbanks, Alaska, in an experiment that seeks to reveal how auroral substorms affect the behavior and composition of Earth’s far upper atmosphere. 
      The experiment’s outcome could upend a long-held theory about the aurora’s interaction with the thermosphere. It may also improve space weather forecasting, critical as the world becomes increasingly reliant on satellite-based devices such as GPS units in everyday life.
      Colorful ribbons of aurora sway with geomagnetic activity above the launch pads of Poker Flat Research Range. NASA/Rachel Lense The University of Alaska Fairbanks (UAF) Geophysical Institute owns Poker Flat, located 20 miles north of Fairbanks, and operates it under a contract with NASA’s Wallops Flight Facility in Virginia, which is part of NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
      The experiment, titled Auroral Waves Excited by Substorm Onset Magnetic Events, or AWESOME, features one four-stage rocket and two two-stage rockets all launching in an approximately three-hour period.
      Colorful vapor tracers from the largest of the three rockets should be visible across much of northern Alaska. The launch window is March 24 through April 6.
      The mission, led by Mark Conde, a space physics professor at UAF, involves about a dozen UAF graduate student researchers at several ground monitoring sites in Alaska at Utqiagvik, Kaktovik, Toolik Lake, Eagle, and Venetie, as well as Poker Flat.  NASA delivers, assembles, tests, and launches the rockets.
      “Our experiment asks the question, when the aurora goes berserk and dumps a bunch of heat in the atmosphere, how much of that heat is spent transporting the air upward in a continuous convective plume and how much of that heat results in not only vertical but also horizontal oscillations in the atmosphere?” Conde said.
      Confirming which process is dominant will reveal the breadth of the mixing and the related changes in the thin air’s characteristics.
      “Change in composition of the atmosphere has consequences,” Conde said. “And we need to know the extent of those consequences.”
      Most of the thermosphere, which reaches from about 50 to 350 miles above the surface, is what scientists call “convectively stable.” That means minimal vertical motion of air, because the warmer air is already at the top, due to absorption of solar radiation.
      A technician with NASA’s Wallops Flight Facility sounding rocket office works on one of the payload sections of the rocket that will launch for the AWESOME campaign. NASA/Lee Wingfield When auroral substorms inject energy and momentum into the middle and lower thermosphere (roughly 60 to 125 miles up), it upsets that stability. That leads to one prevailing theory — that the substorms’ heat is what causes the vertical-motion churn of the thermosphere.
      Conde believes instead that acoustic-buoyancy waves are the dominant mixing force and that vertical convection has a much lesser role. Because acoustic-buoyancy waves travel vertically and horizontally from where the aurora hits, the aurora-caused atmospheric changes could be occurring over a much broader area than currently believed.
      Better prediction of impacts from those changes is the AWESOME mission’s practical goal.
      “I believe our experiment will lead to a simpler and more accurate method of space weather prediction,” Conde said.
      Two two-stage, 42-foot Terrier-Improved Malemute rockets are planned to respectively launch about 15 minutes and an hour after an auroral substorm begins. A four-stage, 70-foot Black Brant XII rocket is planned to launch about five minutes after the second rocket. 
      The first two rockets will release tracers at altitudes of 50 and 110 miles to detect wind movement and wave oscillations. The third rocket will release tracers at five altitudes from 68 to 155 miles.
      Pink, blue, and white vapor traces should be visible from the third rocket for 10 to 20 minutes. Launches must occur in the dawn hours, with sunlight hitting the upper altitudes to activate the vapor tracers from the first rocket but darkness at the surface so ground cameras can photograph the tracers’ response to air movement.
      By Rod Boyce
      University of Alaska Fairbanks Geophysical Institute 
      NASA Media Contact: Sarah Frazier 
      Share








      Details
      Last Updated Mar 21, 2025 Related Terms
      Sounding Rockets Goddard Space Flight Center Heliophysics Heliophysics Division Heliophysics Research Program Science & Research Science Mission Directorate Sounding Rockets Program Uncategorized Wallops Flight Facility Explore More
      2 min read Hubble Captures a Neighbor’s Colorful Clouds


      Article


      7 hours ago
      11 min read The Earth Observer Editor’s Corner: January–March 2025


      Article


      24 hours ago
      5 min read Celebrating 25 Years of Terra


      Article


      24 hours ago
      Keep Exploring Discover Related Topics
      Missions



      Humans in Space



      Climate Change



      Solar System


      View the full article
    • By NASA
      3 min read
      Preparations for Next Moonwalk Simulations Underway (and Underwater)
      NASA / Lillian Gipson NASA has selected three university teams to help solve 21st century aviation challenges that could transform the skies above our communities. 
      As part of NASA’s University Leadership Initiative (ULI), both graduate and undergraduate students on faculty-led university teams will contribute directly to real-world flight research while gaining hands-on experience working with partners from other universities and industry. 
      By combining faculty expertise, student innovation, and industry experience, these three teams will advance NASA’s vision for the future of 21st century aviation.
      koushik datta
      NASA Project Manager
      This is NASA’s eighth round of annual ULI awards. Research topics include: 
      New aviation systems for safer, more efficient flight operations   Improved communications frequency usage for more effective and reliable information transfer  Autonomous flight capabilities that could advance research in areas such as NASA’s Advanced Air Mobility mission  “By combining faculty expertise, student innovation, and industry experience, these three teams will advance NASA’s vision for the future of 21st century aviation,” said Koushik Datta, NASA University Innovation project manager at the Agency’s Ames Research Center in California. 
      This eighth round of annual ULI selections would lead to awards totaling up to $20.7 million for the three teams during the next three years. For each team, the proposing university will serve as lead. The new ULI selections are: 
      Florida Institute of Technology, Melbourne, Florida 
      The team will create a framework for developing trustworthy increasingly autonomous aviation safety systems, such as those that could potentially employ artificial intelligence and machine learning.  
      Team members include: The Pennsylvania State University in University Park; North Carolina Agricultural and Technical State University in Greensboro; University of Florida in Gainesville; Stanford University in California; Santa Fe Community College in New Mexico; and the companies Collins Aerospace of Charlotte in North Carolina; and ResilienX of Syracuse, New York. 
      University of Colorado Boulder 
      This team will investigate tools for understanding and leveraging the complex communications environment of collaborative, autonomous airspace systems.  
      Team members include: Massachusetts Institute of Technology in Cambridge; The University of Texas at El Paso; University of Colorado in Colorado Springs; Stanford University in California; University of Minnesota Twin Cities in Minneapolis, North Carolina State University in Raleigh; University of California inSanta Barbara; El Paso Community College in Texas; Durham Technical Community College in North Carolina; the Center for Autonomous Air Mobility and Sensing research partnership; the company Aurora Flight Sciences, a Boeing Company, in Manassas, Virginia; and the nonprofit Charles Stark Draper Laboratory in Cambridge, Massachusetts. 
      Embry-Riddle Aeronautical University, Daytona Beach, Florida 
      This team will research continuously updating, self-diagnostic vehicle health management to enhance the safety and reliability of Advanced Air Mobility vehicles.  
      Team members include: Georgia Institute of Technology in Atlanta; The University of Texas at Arlington; University of Southern California in Los Angeles; the company Collins Aerospace of Charlotte, North Carolina; and the Argonne National Laboratory. 
      NASA’s ULI is managed by the agency’s University Innovation project, which also includes the University Student Research Challenge and the Gateways to Blue Skies competition.
      Watch the NASA Aeronautics solicitations page for the announcement of when the next opportunity will be to submit a proposal for consideration during the next round of ULI selections. 
      About the Author
      John Gould
      Aeronautics Research Mission DirectorateJohn Gould is a member of NASA Aeronautics' Strategic Communications team at NASA Headquarters in Washington, DC. He is dedicated to public service and NASA’s leading role in scientific exploration. Prior to working for NASA Aeronautics, he was a spaceflight historian and writer, having a lifelong passion for space and aviation.
      Facebook logo @NASA@NASAaero@NASA_es @NASA@NASAaero@NASA_es Instagram logo @NASA@NASAaero@NASA_es Linkedin logo @NASA Explore More
      2 min read NASA Marks 110 Years Since Founding of Predecessor Organization
      Article 1 week ago 3 min read NASA’s X-59 Completes Electromagnetic Testing
      Article 2 weeks ago 4 min read NASA University Research Program Makes First Award to a Community College Project
      Article 2 weeks ago Keep Exploring Discover More Topics From NASA
      Missions
      Artemis
      Aeronautics STEM
      Explore NASA’s History
      Share
      Details
      Last Updated Mar 10, 2025 EditorJim BankeContactSteven Holzsteven.m.holz@nasa.gov Related Terms
      University Leadership Initiative Aeronautics Flight Innovation Transformative Aeronautics Concepts Program University Innovation View the full article
    • By NASA
      X-ray: NASA/CXC/SAO/Univ Mexico/S. Estrada-Dorado et al.; Ultraviolet: NASA/JPL; Optical: NASA/ESA/STScI (M. Meixner)/NRAO (T.A. Rector); Infrared: ESO/VISTA/J. Emerson; Image Processing: NASA/CXC/SAO/K. Arcand; A planet may have been destroyed by a white dwarf at the center of a planetary nebula — the first time this has been seen. As described in our latest press release, this would explain a mysterious X-ray signal that astronomers have detected from the Helix Nebula for over 40 years. The Helix is a planetary nebula, a late-stage star like our Sun that has shed its outer layers leaving a small dim star at its center called a white dwarf.
      This composite image contains X-rays from Chandra (magenta), optical light data from Hubble (orange, light blue), infrared data from ESO (gold, dark blue), and ultraviolet data from GALEX (purple) of the Helix Nebula. Data from Chandra indicates that this white dwarf has destroyed a very closely orbiting planet.
      This artist’s impression shows a planet (left) that has approached too close to a white dwarf (right) and been torn apart by tidal forces from the star. The white dwarf is in the center of a planetary nebula depicted by the blue gas in the background. The planet is part of a planetary system, which includes one planet in the upper left and another in the lower right. The besieged planet could have initially been a considerable distance from the white dwarf but then migrated inwards by interacting with the gravity of other planets in the system.CXC/SAO/M.Weiss An artist’s concept shows a planet (left) that has approached too close to a white dwarf (right) and is being torn apart by tidal forces from the star. The white dwarf is in the center of a planetary nebula depicted by the blue gas in the background. The planet is part of a planetary system, which includes one planet in the upper left and another in the lower right. The besieged planet could have initially been a considerable distance from the white dwarf but then migrated inwards by interacting with the gravity of the other planets in the system.
      Eventually debris from the planet will form a disk around the white dwarf and fall onto the star’s surface, creating the mysterious signal in X-rays that astronomers have detected for decades.
      Dating back to 1980, X-ray missions, such as the Einstein Observatory and ROSAT telescope, have picked up an unusual reading from the center of the Helix Nebula. They detected highly energetic X-rays coming from the white dwarf at the center of the Helix Nebula named WD 2226-210, located only 650 light-years from Earth. White dwarfs like WD 2226-210 do not typically give off strong X-rays.
      In about 5 billion years, our Sun will run out of fuel and expand, possibly engulfing Earth. These end stages of a star’s life can be utterly beautiful as is the case with this planetary nebula called the Helix Nebula.X-ray: NASA/CXC/SAO/Univ Mexico/S. Estrada-Dorado et al.; Ultraviolet: NASA/JPL; Optical: NASA/ESA/STScI (M. Meixner)/NRAO (T.A. Rector); Infrared: ESO/VISTA/J. Emerson; Image Processing: NASA/CXC/SAO/K. Arcand; A new study featuring the data from Chandra and XMM-Newton may finally have settled the question of what is causing these X-rays from WD 2226-210: this X-ray signal could be the debris from a destroyed planet being pulled onto the white dwarf. If confirmed, this would be the first case of a planet seen to be destroyed by the central star in a planetary nebula.
      Observations by ROSAT, Chandra, and XMM-Newton between 1992 and 2002 show that the X-ray signal from the white dwarf has remained approximately constant in brightness during that time. The data, however, suggest there may be a subtle, regular change in the X-ray signal every 2.9 hours, providing evidence for the remains of a planet exceptionally close to the white dwarf.
      Previously scientists determined that a Neptune-sized planet is in a very close orbit around the white dwarf — completing one revolution in less than three days. The researchers in this latest study conclude that there could have been a planet like Jupiter even closer to the star. The besieged planet could have initially been a considerable distance from the white dwarf but then migrated inwards by interacting with the gravity of other planets in the system. Once it approached close enough to the white dwarf the gravity of the star would have partially or completely torn the planet apart.
      WD 2226-210 has some similarities in X-ray behavior to two other white dwarfs that are not inside planetary nebulas. One is possibly pulling material away from a planet companion, but in a more sedate fashion without the planet being quickly destroyed. The other white dwarf is likely dragging material from the vestiges of a planet onto its surface. These three white dwarfs may constitute a new class of variable, or changing, object.
      A paper describing these results appears in The Monthly Notices of the Royal Astronomical Society and is available online. The authors of the paper are Sandino Estrada-Dorado (National Autonomous University of Mexico), Martin Guerrero (The Institute of Astrophysics of Andalusia in Spain), Jesús Toala (National Autonomous University of Mexico), Ricardo Maldonado (National Autonomous University of Mexico), Veronica Lora (National Autonomous University of Mexico), Diego Alejandro Vasquez-Torres (National Autonomous University of Mexico), and You-Hua Chu (Academia Sinica in Taiwan).
      NASA’s Marshall Space Flight Center manages the Chandra program. The Smithsonian Astrophysical Observatory’s Chandra X-ray Center controls science operations from Cambridge, Massachusetts, and flight operations from Burlington, Massachusetts.
      Read more from NASA’s Chandra X-ray Observatory.
      Learn more about the Chandra X-ray Observatory and its mission here:
      https://www.nasa.gov/chandra
      https://chandra.si.edu
      Visual Description
      This release features two images; a composite image of the Helix Nebula, and an artist’s rendering of a planet’s destruction, which may be occurring in the nebula’s core.
      The Helix Nebula is a cloud of gas ejected by a dying star, known as a white dwarf. In the composite image, the cloud of gas strongly resembles a creature’s eye. Here, a hazy blue cloud is surrounded by misty, concentric rings of pale yellow, rose pink, and blood orange. Each ring appears dusted with flecks of gold, particularly the outer edges of the eye-shape.
      The entire image is speckled with glowing dots in blues, whites, yellows, and purples. At the center of the hazy blue gas cloud, a box has been drawn around some of these dots including a bright white dot with a pink outer ring, and a smaller white dot. The scene which may be unfolding inside this box has been magnified in the artist’s rendering.
      The artist’s digital rendering shows a possible cause of the large white dot with the pink outer ring. A brilliant white circle near our upper right shows a white dwarf, the ember of a dying star. At our lower left, in the relative foreground of the rendering, is what remains of a planet. Here, the planet resembles a giant boulder shedding thousands of smaller rocks. These rocks flow off the planet’s surface, pulled back toward the white dwarf in a long, swooping tail. Glowing orange fault lines mar the surface of the crumbling planet. In our upper left and lower right, inside the hazy blue clouds which blanket the rendering, are two other, more distant planets. After the rocks from the planet start striking the surface of the white dwarf, X-rays should be produced.
      News Media Contact
      Megan Watzke
      Chandra X-ray Center
      Cambridge, Mass.
      617-496-7998
      mwatzke@cfa.harvard.edu
      Lane Figueroa
      Marshall Space Flight Center, Huntsville, Alabama
      256-544-0034
      lane.e.figueroa@nasa.gov
      Explore More
      6 min read NASA’s Hubble Finds Kuiper Belt Duo May Be Trio
      The puzzle of predicting how three gravitationally bound bodies move in space has challenged mathematicians…
      Article 12 mins ago 6 min read NASA’s Webb Exposes Complex Atmosphere of Starless Super-Jupiter
      An international team of researchers has discovered that previously observed variations in brightness of a…
      Article 1 day ago 1 min read Hubble Captures New View of Colorful Veil
      In this NASA/ESA Hubble Space Telescope image, Hubble once again lifts the veil on a…
      Article 4 days ago Keep Exploring Discover More Topics From NASA
      Missions
      Humans in Space
      Climate Change
      Solar System
      View the full article
    • By NASA
      5 Min Read Planetary Alignments and Planet Parades
      A sky chart showing Mars, Jupiter, Saturn, and Venus in a “planet parade.” Credits:
      NASA/JPL-Caltech On most nights, weather permitting, you can spot at least one bright planet in the night sky. While two or three planets are commonly visible in the hours around sunset, occasionally four or five bright planets can be seen simultaneously with the naked eye. These events, often called “planet parades” or “planetary alignments,” can generate significant public interest. Though not exceedingly rare, they’re worth observing since they don’t happen every year.
      Why Planets Appear Along a Line in The Sky
      “Planet parade” isn’t a technical term in astronomy, and “planetary alignment” can refer to several different phenomena. As the planets of our solar system orbit the Sun, they occasionally line up in space in events called oppositions and conjunctions. A planetary alignment can also refer to apparent lineups in our sky with other planets, the Moon, or bright stars.
      The planets of our solar system always appear along a line on the sky. This line, referred to as the ecliptic, represents the plane in which the planets orbit, seen from our position within the plane itself. NASA/Preston Dyches When it comes to this second type of planetary alignment, it’s important to understand that planets always appear along a line or arc across the sky. This occurs because the planets orbit our Sun in a relatively flat, disc-shaped plane. From Earth, we’re looking into that solar system plane from within. We see the racetrack of the planets from the perspective of one of the racers ourselves. When viewed edge-on, this disc appears as a line, which we call the ecliptic or ecliptic plane.
      So, while planet alignment itself isn’t unusual, what makes these events special is the opportunity to observe multiple planets simultaneously with the naked eye.
      Will the Planets Actually be Visible?
      Before preparing to observe a planet parade, we have to consider how high the planets will appear above the horizon. For most observers to see a planet with the naked eye, it needs to be at least a few degrees above the horizon, and10 degrees or higher is best. This is crucial because Earth’s atmosphere near the ground dims celestial objects as they rise or set. Even bright planets become difficult or impossible to spot when they’re too low, as their light gets scattered and absorbed on its path to your eye. Buildings, trees, and other obstructions often block the view near the horizon as well.
      This visibility challenge is particularly notable after sunset or before sunrise, where the sky is still glowing. If a planet appears very low within the sunset glow, it is very difficult to observe.
      The Planets You Can See, and Those You Can’t
      Five planets are visible without optical aid: Mercury, Venus, Mars, Jupiter, and Saturn. Ancient civilizations recognized these worlds as bright lights that wandered across the starscape, while the background stars remained fixed in place. In fact, the word “planet” comes to us from the Greek word for “wanderer.”
      The solar system includes two additional major planets, Uranus and Neptune, plus numerous dwarf planets like Pluto and Ceres. Uranus and Neptune orbit in the dim, cold depths of the outer solar system. Neptune absolutely requires a telescope to observe. While Uranus is technically bright enough to detect with good eyesight, it’s quite faint and requires dark skies and precise knowledge of its location among similarly faint stars, so a telescope is recommended. As we’ll discuss in the next section, planet parades necessarily must be observed in twilight before dawn or after sunset, and this is not a good time to try observing extremely faint objects like Uranus and Neptune.
      Thus, claims about rare six- or seven-planet alignments which include Uranus and Neptune should be viewed with the understanding that these two distant planets will not be visible to the unaided eye.
      What Makes Multi-Planet Lineups Special
      Lineups of four or five planet naked-eye planets with optimal visibility typically occur every few years. Mars, Jupiter, and Saturn are frequently seen in the night sky, but the addition of Venus and Mercury make four- and five-planet lineups particularly noteworthy. Both orbit closer to the Sun than Earth, with smaller, faster orbits than the other planets. Venus is visible for only a couple of months at a time when it reaches its greatest separation from the Sun (called elongation), appearing just after sunset or before sunrise. Mercury, completing its orbit in just 88 days, is visible for only a couple of weeks (or even a few days) at a time just after sunset or just before sunrise.
      Planet parades aren’t single-day events, as the planets move too slowly for that. Generally, multi-planet viewing opportunities last for weeks to a month or more. Even five-planet events last for several days as Mercury briefly emerges from and returns to the Sun’s glare.
      In summary, while they aren’t once-in-a-lifetime events, planetary parades afford an uncommon opportunity to look up and appreciate our place in our solar system, with diverse worlds arrayed across the sky before our very eyes.
      Other Planet Lineups
      Other recent and near-future multi-planet viewing opportunities:
      January 2016 – Four planets visible at once before sunrise Late April to Late August 2022 – Four planets visible at once before sunrise Mid-June to Early July 2022 – Five planets visible at once before sunrise January to mid-February 2025 – Four planets visible at once after sunset Late August 2025 – Four planets visible at once before sunrise Late October 2028 – Five planets visible at once before sunrise Late February 2034 – Five planets visible at once after sunset (Venus and Mercury challenging to observe) About the January/February 2025 Planet Parade
      The current four-planet lineup concludes by mid-February, as Saturn sinks increasingly lower in the sky each night after sunset. By mid-to-late February, Saturn appears less than 10 degrees above the horizon as sunset fades, making it difficult to observe for most people. While Mercury briefly joins Saturn in the post-sunset glow at the end of February, both planets will be too low and faint for most observers to spot.
      Keep Exploring Discover More Topics From NASA
      Skywatching



      Planets



      Solar System Exploration



      Moons


      View the full article
  • Similar Videos

  • Check out these Videos

×
×
  • Create New...