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By NASA
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Preparations for Next Moonwalk Simulations Underway (and Underwater)
JunoCam, the visible light imager aboard NASA’s Juno, captured this enhanced-color view of Ju-piter’s northern high latitudes from an altitude of about 36,000 miles (58,000 kilometers) above the giant planet’s cloud tops during the spacecraft’s 69th flyby on Jan. 28, 2025. Image data: NASA/JPL-Caltech/SwRI/MSSS Image processing: Jackie Branc (CC BY) New data from the agency’s Jovian orbiter sheds light on the fierce winds and cyclones of the gas giant’s northern reaches and volcanic action on its fiery moon.
NASA’s Juno mission has gathered new findings after peering below Jupiter’s cloud-covered atmosphere and the surface of its fiery moon, Io. Not only has the data helped develop a new model to better understand the fast-moving jet stream that encircles Jupiter’s cyclone-festooned north pole, it’s also revealed for the first time the subsurface temperature profile of Io, providing insights into the moon’s inner structure and volcanic activity.
Team members presented the findings during a news briefing in Vienna on Tuesday, April 29, at the European Geosciences Union General Assembly.
“Everything about Jupiter is extreme. The planet is home to gigantic polar cyclones bigger than Australia, fierce jet streams, the most volcanic body in our solar system, the most powerful aurora, and the harshest radiation belts,” said Scott Bolton, principal investigator of Juno at the Southwest Research Institute in San Antonio. “As Juno’s orbit takes us to new regions of Jupiter’s complex system, we’re getting a closer look at the immensity of energy this gas giant wields.”
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Made with data from the JIRAM instrument aboard NASA’s Juno, this animation shows the south polar region of Jupiter’s moon Io during a Dec. 27, 2024, flyby. The bright spots are locations with higher temperatures caused by volcanic activity; the gray areas resulted when Io left the field of view.NASA/JPL/SwRI/ASI – JIRAM Team (A.M.) Lunar Radiator
While Juno’s microwave radiometer (MWR) was designed to peer beneath Jupiter’s cloud tops, the team has also trained the instrument on Io, combining its data with Jovian Infrared Auroral Mapper (JIRAM) data for deeper insights.
“The Juno science team loves to combine very different datasets from very different instruments and see what we can learn,” said Shannon Brown, a Juno scientist at NASA’s Jet Propulsion Laboratory in Southern California. “When we incorporated the MWR data with JIRAM’s infrared imagery, we were surprised by what we saw: evidence of still-warm magma that hasn’t yet solidified below Io’s cooled crust. At every latitude and longitude, there were cooling lava flows.”
The data suggests that about 10% of the moon’s surface has these remnants of slowly cooling lava just below the surface. The result may help provide insight into how the moon renews its surface so quickly as well as how as well as how heat moves from its deep interior to the surface.
“Io’s volcanos, lava fields, and subterranean lava flows act like a car radiator,” said Brown, “efficiently moving heat from the interior to the surface, cooling itself down in the vacuum of space.”
Looking at JIRAM data alone, the team also determined that the most energetic eruption in Io’s history (first identified by the infrared imager during Juno’s Dec. 27, 2024, Io flyby) was still spewing lava and ash as recently as March 2. Juno mission scientists believe it remains active today and expect more observations on May 6, when the solar-powered spacecraft flies by the fiery moon at a distance of about 55,300 miles (89,000 kilometers).
This composite image, derived from data collected in 2017 by the JIRAM instrument aboard NASA’s Juno, shows the central cyclone at Jupiter’s north pole and the eight cy-clones that encircle it. Data from the mission indicates these storms are enduring fea-tures.NASA/JPL-Caltech/SwRI/ASI/INAF/JIRAM Colder Climes
On its 53rd orbit (Feb 18, 2023), Juno began radio occultation experiments to explore the gas giant’s atmospheric temperature structure. With this technique, a radio signal is transmitted from Earth to Juno and back, passing through Jupiter’s atmosphere on both legs of the journey. As the planet’s atmospheric layers bend the radio waves, scientists can precisely measure the effects of this refraction to derive detailed information about the temperature and density of the atmosphere.
So far, Juno has completed 26 radio occultation soundings. Among the most compelling discoveries: the first-ever temperature measurement of Jupiter’s north polar stratospheric cap reveals the region is about 11 degrees Celsius cooler than its surroundings and is encircled by winds exceeding 100 mph (161 kph).
Polar Cyclones
The team’s recent findings also focus on the cyclones that haunt Jupiter’s north. Years of data from the JunoCam visible light imager and JIRAM have allowed Juno scientists to observe the long-term movement of Jupiter’s massive northern polar cyclone and the eight cyclones that encircle it. Unlike hurricanes on Earth, which typically occur in isolation and at lower latitudes, Jupiter’s are confined to the polar region.
By tracking the cyclones’ movements across multiple orbits, the scientists observed that each storm gradually drifts toward the pole due to a process called “beta drift” (the interaction between the Coriolis force and the cyclone’s circular wind pattern). This is similar to how hurricanes on our planet migrate, but Earthly cyclones break up before reaching the pole due to the lack of warm, moist air needed to fuel them, as well as the weakening of the Coriolis force near the poles. What’s more, Jupiter’s cyclones cluster together while approaching the pole, and their motion slows as they begin interacting with neighboring cyclones.
“These competing forces result in the cyclones ‘bouncing’ off one another in a manner reminiscent of springs in a mechanical system,” said Yohai Kaspi, a Juno co-investigator from the Weizmann Institute of Science in Israel. “This interaction not only stabilizes the entire configuration, but also causes the cyclones to oscillate around their central positions, as they slowly drift westward, clockwise, around the pole.”
The new atmospheric model helps explain the motion of cyclones not only on Jupiter, but potentially on other planets, including Earth.
“One of the great things about Juno is its orbit is ever-changing, which means we get a new vantage point each time as we perform a science flyby,” said Bolton. “In the extended mission, that means we’re continuing to go where no spacecraft has gone before, including spending more time in the strongest planetary radiation belts in the solar system. It’s a little scary, but we’ve built Juno like a tank and are learning more about this intense environment each time we go through it.”
More About Juno
NASA’s Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Juno mission for the principal investigator, Scott Bolton, of the Southwest Research Institute in San Antonio. Juno is part of NASA’s New Frontiers Program, which is managed at NASA’s Marshall Space Flight Center in Huntsville, Alabama, for the agency’s Science Mission Directorate in Washington. The Italian Space Agency funded the Jovian InfraRed Auroral Mapper. Lockheed Martin Space in Denver built and operates the spacecraft. Various other institutions around the U.S. provided several of the other scientific instruments on Juno.
More information about Juno is at: https://www.nasa.gov/juno
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By European Space Agency
Video: 00:02:01 ESA’s state-of-the-art Biomass satellite has launched aboard a Vega-C rocket from Europe’s Spaceport in French Guiana. The rocket lifted off on 29 April 2025 at 11:15 CEST (06:15 local time).
In orbit, this latest Earth Explorer mission will provide vital insights into the health and dynamics of the world’s forests, revealing how they are changing over time and, critically, enhancing our understanding of their role in the global carbon cycle. It is the first satellite to carry a fully polarimetric P-band synthetic aperture radar for interferometric imaging. Thanks to the long wavelength of P-band, around 70 cm, the radar signal can slice through the whole forest layer to measure the ‘biomass’, meaning the woody trunks, branches and stems, which is where trees store most of their carbon.
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By NASA
NASA’s Nancy Grace Roman Space Telescope team shared Thursday the designs for the three core surveys the mission will conduct after launch. These observation programs are designed to investigate some of the most profound mysteries in astrophysics while enabling expansive cosmic exploration that will revolutionize our understanding of the universe.
“Roman’s setting out to do wide, deep surveys of the universe in a way that will help us answer questions about how dark energy and dark matter govern cosmic evolution, and the demographics of worlds beyond our solar system,” said Gail Zasowski, an associate professor at the University of Utah and co-chair of the ROTAC (Roman Observations Time Allocation Committee). “But the overarching goal is that the surveys have broad appeal and numerous science applications. They were designed by and for the astronomical community to maximize the science they’ll enable.”
NASA’s Nancy Grace Roman Space Telescope’s three main observing programs, highlighted in this infographic, can enable astronomers to view the universe as never before, revealing billions of cosmic objects strewn across enormous swaths of space-time.Credit: NASA’s Goddard Space Flight Center Roman’s crisp, panoramic view of space and fast survey speeds provide the opportunity for astronomers to study the universe as never before. The Roman team asked the science community to detail the topics they’d like to study through each of Roman’s surveys and selected committees of scientists across many organizations to evaluate the range of possibilities and formulate three compelling options for each.
In April, the Roman team received the recommendations and has now determined the survey designs. These observations account for no more than 75 percent of Roman’s surveys during its five-year primary mission, with the remainder allocated to additional observations that will be proposed and developed by the science community in later opportunities.
“These survey designs are the culmination of two years of input from more than 1,000 scientists from over 350 institutions across the globe,” said Julie McEnery, Roman’s senior project scientist at NASA Goddard. “We’re thrilled that we’ve been able to hear from so many of the people who’ll use the data after launch to investigate everything from objects in our outer solar system, planets across our galaxy, dark matter and dark energy, to exploding stars, growing black holes, galaxies by the billions, and so much more.”
With all major hardware now delivered, Roman has entered its final phase of preparation for launch, undergoing integration and key environmental testing at NASA Goddard. Roman is targeted to launch by May 2027, with the team working toward a potential launch window that opens in October 2026.
This infographic describes the High-Latitude Wide-Area Survey that will be conducted by NASA’s Nancy Grace Roman Space Telescope. This observation program has three components, covering more than 5,000 square degrees (about 12 percent of the sky) altogether in just under a year and a half. The main part covers about 2,500 square degrees, doing both spectroscopy (splitting light into individual colors to study patterns that reveal detailed information) and imaging in multiple filters (which allow astronomers to select specific wavelengths of light) to provide the rich dataset needed for precise studies of our universe. A wider component spans more than twice the area using a single filter, specifically covering a large area that can be viewed by ground-based telescopes located in both the northern and southern hemispheres. The final component focuses on a smaller region to provide a deeper view that will help astronomers study faint, distant galaxies.Credit: NASA’s Goddard Space Flight Center High-Latitude Wide-Area Survey
Roman’s largest survey, the High-Latitude Wide-Area Survey, combines the powers of imaging and spectroscopy to unveil more than a billion galaxies strewn across a wide swath of cosmic time. Roman can look far from the dusty plane of our Milky Way galaxy (that’s what the “high-latitude” part of the survey name means), looking up and out of the galaxy rather than through it to get the clearest view of the distant cosmos.
The distribution and shapes of galaxies in Roman’s enormous, deep images can help us understand the nature of dark energy — a pressure that seems to be speeding up the universe’s expansion — and how invisible dark matter, which Roman will detect by its gravitational effects, influences the evolution of structure in our universe.
For the last two years, researchers have been discussing ways to expand the range of scientific topics that can be studied using the same dataset. That includes studying galaxy evolution, star formation, cosmic voids, the matter between galaxies, and much more.
This infographic describes the High-Latitude Time-Domain Survey that will be conducted by NASA’s Nancy Grace Roman Space Telescope. The survey’s main component covers over 18 square degrees — a region of sky as large as 90 full moons — and sees supernovae that occurred up to about 8 billion years ago. Smaller areas within the survey can pierce even farther, potentially back to when the universe was around a billion years old. The survey is split between the northern and southern hemispheres, located in regions of the sky that will be continuously visible to Roman. The bulk of the survey consists of 30-hour observations every five days for two years in the middle of Roman’s five-year primary mission.Credit: NASA’s Goddard Space Flight Center High-Latitude Time-Domain Survey
Roman’s High-Latitude Time-Domain Survey can probe our dynamic universe by observing the same region of the cosmos repeatedly. Stitching these observations together to create movies can allow scientists to study how celestial objects and phenomena change over time periods of days to years.
This survey can probe dark energy by finding and studying many thousands of a special type of exploding star called type Ia supernovae. These stellar cataclysms allow scientists to measure cosmic distances and trace the universe’s expansion.
“Staring at a large volume of the sky for so long will also reveal black holes being born as neutron stars merge, and tidal disruption events –– flares released by stars falling into black holes,” said Saurabh Jha, a professor at Rutgers University in New Brunswick, New Jersey, and ROTAC co-chair. “It will also allow astronomers to explore variable objects, like active galaxies and binary systems. And it enables more open-ended cosmic exploration than most other space telescopes can do, offering a chance to answer questions we haven’t yet thought to ask.”
This infographic describes the Galactic Bulge Time-Domain Survey that will be conducted by NASA’s Nancy Grace Roman Space Telescope. The smallest of Roman’s core surveys, this observation program consists of repeat visits to six fields covering 1.7 square degrees total. One field pierces the very center of the galaxy, and the others are nearby — all in a region of the sky that will be visible to Roman for two 72-day stretches each spring and fall. The survey mainly consists of six seasons (three early on, and three toward the end of Roman’s primary mission), during which Roman views each field every 12 minutes. Roman also views the six fields with less intensity at other times throughout the mission, allowing astronomers to detect microlensing events that can last for years, signaling the presence of isolated, stellar-mass black holes.Credit: NASA’s Goddard Space Flight Center Galactic Bulge Time-Domain Survey
Unlike the high-latitude surveys, Roman’s Galactic Bulge Time-Domain Survey will look inward to provide one of the deepest views ever of the heart of our Milky Way galaxy. Roman’s crisp resolution and infrared view can allow astronomers to watch hundreds of millions of stars in search of microlensing signals — gravitational boosts of a background star’s light that occur when an intervening object passes nearly in front of it. While astronomers have mainly discovered star-hugging worlds, Roman’s microlensing observations can find planets in the habitable zone of their star and farther out, including analogs of every planet in our solar system except Mercury.
The same set of observations can reveal “rogue” planets that drift through the galaxy unbound to any star, brown dwarfs (“failed stars” too lightweight to power themselves by fusion the way stars do), and stellar corpses like neutron stars and white dwarfs. And scientists could discover 100,000 new worlds by seeing stars periodically get dimmer as an orbiting planet passes in front of them, events called transits. Scientists can also study the stars themselves, detecting “starquakes” on a million giant stars, the result of sound waves reverberating through their interiors that can reveal information about their structures, ages, and other properties.
Data from all of Roman’s surveys will be made public as soon as it is processed, with no periods of exclusive access.
“Roman’s unprecedented data will offer practically limitless opportunities for astronomers to explore all kinds of cosmic topics,” McEnery said. “We stand to learn a tremendous amount of new information about the universe very rapidly after the mission launches.”
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By Ashley Balzer
NASA’s Goddard Space Flight Center, Greenbelt, Md.
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Last Updated Apr 24, 2025 EditorAshley BalzerContactAshley Balzerashley.m.balzer@nasa.govLocationNASA Goddard Space Flight Center Related Terms
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By NASA
Explore Hubble Hubble Home Overview About Hubble The History of Hubble Hubble Timeline Why Have a Telescope in Space? Hubble by the Numbers At the Museum FAQs Impact & Benefits Hubble’s Impact & Benefits Science Impacts Cultural Impact Technology Benefits Impact on Human Spaceflight Astro Community Impacts Science Hubble Science Science Themes Science Highlights Science Behind Discoveries Hubble’s Partners in Science Universe Uncovered Explore the Night Sky Observatory Hubble Observatory Hubble Design Mission Operations Missions to Hubble Hubble vs Webb Team Hubble Team Career Aspirations Hubble Astronauts News Hubble News Social Media Media Resources Multimedia Multimedia Images Videos Sonifications Podcasts e-Books Online Activities Lithographs Fact Sheets Posters Hubble on the NASA App Glossary More 35th Anniversary Online Activities 5 Min Read NASA’s Hubble Tracks a Roaming Magnetar of Unknown Origin
This is an artist’s impression of a magnetar, a special type of neutron star with an incredibly strong magnetic field. Credits:
ESA Researchers using NASA’s Hubble Space Telescope have discovered the magnetar called SGR 0501+4516 is traversing our galaxy from an unknown place of origin. Researchers say that this runaway magnetar is the likeliest candidate in our Milky Way galaxy for a magnetar that was not born in a supernova explosion as initially predicted. It is so strange it might even offer clues to the mechanism behind events known as fast radio bursts.
“Magnetars are neutron stars — the dead remnants of stars — composed entirely of neutrons. What makes magnetars unique is their extreme magnetic fields,” said Ashley Chrimes, lead author of the discovery paper published in the April 15 journal Astronomy & Astrophysics. Chrimes is a European Space Agency Research Fellow at the European Space Research and Technology Center in the Netherlands.
Magnetars have comic-book-hero superpowers. A magnetar has a magnetic field about a trillion times more powerful than Earth’s magnetosphere. If a magnetar flew by Earth at half the Moon’s distance, its intense field would wipe out every credit card on our planet. If a human got within 600 miles, the magnetar would become a proverbial sci-fi death-ray, ripping apart every atom inside the body.
The magnetar’s strangeness was identified with the help of Hubble’s sensitive instruments as well as precise benchmarks from ESA’s (European Space Agency) Gaia spacecraft.
Initially, the mysterious magnetar was discovered in 2008 when NASA’s Swift Observatory spotted brief, intense flashes of gamma rays from the outskirts of the Milky Way. The source, which turned out to be one of only about 30 known magnetars in the Milky Way, was dubbed SGR 0501+4516.
This is an artist’s impression of a magnetar, which is a special type of neutron star with an incredibly strong magnetic field. Neutron stars are some of the most compact and extreme objects in the universe. These stars typically pack more than the mass of the Sun into a sphere of neutrons about 12 miles across. The neutron star is depicted as a white-blueish sphere. The magnetic field is shown as filaments streaming out from its polar regions. Illustration: ESA Because magnetars are neutron stars, the natural explanation for their formation is that they are born in supernovae, when a star explodes and can collapse down to an ultra-dense neutron star. This appeared to be the case for SGR 0501+4516, which is located close to a supernova remnant called HB9. The separation between the magnetar and the center of the supernova remnant on the sky is just 80 arcminutes, or slightly wider than your pinky finger when viewed at the end of your outstretched arm.
But a decade-long study with Hubble cast doubt on the magnetar’s birthplace. After initial observations with ground-based telescopes shortly after SGR 0501+4516’s discovery, researchers used Hubble’s exquisite sensitivity and steady pointing to spot the magnetar’s faint infrared glow in 2010, 2012, and 2020. Each of these images was aligned to a reference frame defined by observations from the Gaia spacecraft, which has crafted an extraordinarily precise three-dimensional map of nearly two billion stars in the Milky Way. This method revealed the subtle motion of the magnetar as it traversed the sky.
“All of this movement we measure is smaller than a single pixel of a Hubble image,” said co-investigator Joe Lyman of the University of Warwick, United Kingdom. “Being able to robustly perform such measurements really is a testament to the long-term stability of Hubble.”
By tracking the magnetar’s position, the team was able to measure the object’s apparent motion across the sky. Both the speed and direction of SGR 0501+4516’s movement showed that the magnetar could not be associated with the nearby supernova remnant. Tracing the magnetar’s trajectory thousands of years into the past showed that there were no other supernova remnants or massive star clusters with which it could be associated.
If SGR 0501+4516 was not born in a supernova, the magnetar must either be older than its estimated 20,000-year age, or it may have formed in another way. Magnetars may also be able to form through the merger of two lower-mass neutron stars or through a process called accretion-induced collapse. Accretion-induced collapse requires a binary star system containing a white dwarf: the core of a dead Sun-like star. If the white dwarf pulls in gas from its companion, it can grow too massive to support itself, leading to an explosion — or possibly the creation of a magnetar.
“Normally, this scenario leads to the ignition of nuclear reactions, and the white dwarf exploding, leaving nothing behind. But it has been theorized that under certain conditions, the white dwarf can instead collapse into a neutron star. We think this might be how SGR 0501 was born,” added Andrew Levan of Radboud University in the Netherlands and the University of Warwick in the United Kingdom.
Understanding Fast Radio Bursts
SGR 0501+4516 is currently the best candidate for a magnetar in our galaxy that may have formed through a merger or accretion-induced collapse. Magnetars that form through accretion-induced collapse could provide an explanation for some of the mysterious fast radio bursts, which are brief but powerful flashes of radio waves. In particular, this scenario may explain the origin of fast radio bursts that emerge from stellar populations too ancient to have recently birthed stars massive enough to explode as supernovae.
“Magnetar birth rates and formation scenarios are among the most pressing questions in high-energy astrophysics, with implications for many of the universe’s most powerful transient events, such as gamma-ray bursts, super-luminous supernovae, and fast radio bursts,” said Nanda Rea of the Institute of Space Sciences in Barcelona, Spain.
The research team has further Hubble observations planned to study the origins of other magnetars in the Milky Way, helping to understand how these extreme magnetic objects form.
The Hubble Space Telescope has been operating for over three decades and continues to make ground-breaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and mission operations. Lockheed Martin Space, based in Denver, also supports mission operations at Goddard. The Space Telescope Science Institute in Baltimore, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.
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This is an artist’s impression of a magnetar, which is a special type of neutron star with an incredibly strong magnetic field.
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Last Updated Apr 15, 2025 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center Contact Media Claire Andreoli
NASA’s Goddard Space Flight Center
Greenbelt, Maryland
claire.andreoli@nasa.gov
Bethany Downer
ESA/Hubble
bethany.downer@esahubble.org
Garching, Germany
Ray Villard
Space Telescope Science Institute
Baltimore, Maryland
Science Ashley Chrimes
ESA-ESTEC/Radboud University
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