Astro Blog

By Robert Sanders , UC Berkeley News.  Excerpt: Jupiter, the most massive planet in our solar system, has correspondingly humongous storms.... Some of these storms also generate terrific bolts of lightning, according to a new study by University of California, Berkeley scientists. Some flashes are 100 times more powerful than lightning on Earth — and possibly much stronger. The results come from analysis of data from NASA’s Juno spacecraft, which has been orbiting the planet since 2016 and scanning the atmosphere with its microwave radiometer, which can detect radio emissions from lightning similar to the radio interference created by lightning on Earth. ...lead author Michael Wong, a planetary scientist at UC Berkeley’s Space Sciences Laboratory...  study  was published March 20 in the journal  AGU Advances ....  Full article at https://news.berkeley.edu/2026/03/23/lightning-bolts-on-jupiter-pack-more-than-100-times-the-power-of-earths-flashes/ .  See also...

By Sarah Stanley , Eos/AGU.  Excerpt: Trapped in a gravitational push and pull between Jupiter and other Jovian moons, Io is constantly being  stretched and compressed . Heat generated by these contortions has melted  pockets  of the moon’s interior so much that Io is our solar system’s most volcanically active body. The  James Webb Space Telescope (JWST)  recently opened up new opportunities to get to know Io. Using data from its Near Infrared Spectrograph—which sees wavelengths corresponding to  different compositions and temperatures — de Pater et al.  have made new discoveries about Io’s volcanoes and atmosphere. The researchers first looked at Io  in November 2022  and found an extremely energetic volcanic eruption in the vicinity of the lava flow field Kanehekili Fluctus. These observations revealed, for the first time, that some volcanoes on Io emit an excited form of sulfur monoxide gas, confirming the team’s 2-decade-old hypoth...

By Sarah Stanley , Eos/AGU.  Excerpt: Spectacular aurorae dance and shimmer nearly continuously at Jupiter’s poles. ...Sometimes, Jupiter’s aurorae grow much brighter for hours or days at a time. ... clarifying the solar wind’s role  in any one brightening event would require taking simultaneous measurements of Jupiter’s magnetosphere and aurorae and their relationship with the solar wind—a difficult undertaking. ...NASA’s  Juno mission  has made such simultaneous measurements possible.  Giles et al.  used data... from two of Juno’s onboard instruments...as Juno neared Jupiter in its elliptical orbit on 6 December, the spacecraft was overtaken by the outer edge of the shrinking magnetosphere before later reentering it closer to Jupiter. ...Another of Juno’s instruments, its ultraviolet spectrograph, measured the aurora’s peak power at this time to be 12 terawatts—6 times its baseline power level. ...the researchers concluded that the powerful auroral d...

By Sarah Stanley , Eos/AGU.  Excerpt: A closer look at previously disregarded observations reveals stronger evidence that a deep ocean lies beneath Callisto’s icy surface. ... Cochrane et al.  have revisited the Galileo data in more detail. Unlike in prior studies, this team incorporated all available magnetic measurements from Galileo’s eight close flybys of Callisto. Their expanded analysis much more strongly suggests that Callisto hosts a subsurface ocean....  Full article at https://eos.org/research-spotlights/jupiters-moon-callisto-is-very-likely-an-ocean-world . 

By Robin George Andrews , Science.  Excerpt: ...Jupiter’s moon Europa ...NASA hopes will greet its Europa Clipper spacecraft, which will begin its journey to the Jupiter system next month. ...Something extraordinary is concealed beneath the ice: a liquid saltwater ocean, potentially as clement and welcoming to life as Earth’s. ...Equipped with a battery of nine science instruments, Clipper will swoop past Europa in a series of nearly 50 ice-skimming flybys, remotely probing the ocean in hopes of finding a chemistry that could support life. ...“We’re not a life search mission. We’re a habitability mission,” says Robert Pappalardo, Clipper’s project scientist at the Jet Propulsion Laboratory (JPL), which manages the mission. But even Pappalardo, a cautious scientist who is constitutionally averse to hyperbole, says finding a hint of life is “not out of the question.”...  Full article at https://www.science.org/content/article/nasa-spacecraft-probe-possibility-life-europa-s-salty...

https://www.mercury-messenger.org/history-culture/galileo-telescope By Shanil Virani, Astronomical Society of the Pacific - Mercury online Excerpt: Between January 7 and January 13, 1610, a series of observations was made that would forever change how we would view the cosmos. The observer detailed in this log book a discovery made using a relatively new invention at that time. The observer had discovered four small, point sources of light very close to the (giant) planet Jupiter. On January 10, one of them disappeared for a short period. The observer attributed the disappearance of the object as being hidden behind Jupiter. Given his extensive observations, he was now forced to conclude that these four points of light were orbiting Jupiter and not Earth. The observer, Galileo Galilei, and his two small pieces of glass would usher in a scientific revolution that reverberates to this day. Until this discovery, and for some 1,500 years prior to Galileo, our ancestors accepted the m...

https://news.berkeley.edu/2023/10/19/webb-telescope-discovers-intense-jet-stream-in-jupiters-atmosphere By Robert Sanders , UC Berkeley News. Excerpt: NASA’s James Webb Space Telescope has discovered a fast-moving jet stream in Jupiter’s atmosphere that is blowing twice as fast as the visible cloud layers below it, creating wind shears that far exceed anything seen on Earth. The high-speed jet stream, which is traveling at 320 miles per hour (515 kilometers per hour) and is more than 3,000 miles (4,800 kilometers) wide, sits over Jupiter’s equator, 15 to 30 miles (25 to 50 kilometers) above the main cloud deck familiar from optical photos. ...winds in the visible cloud layer blow at about 180 mph (250 km/hour). This means that for every kilometer above these visible clouds, the wind speed increases by 7 to 10 kilometers per hour, according to Ricardo Hueso, lead author of a paper describing the findings published today in the journal  Nature Astronomy ....

https://www.nytimes.com/2023/09/15/science/jupiter-comet-flashes.html By Katrina Miller , The New York Times.  Excerpt: Ko Arimatsu, an astronomer at Kyoto University in Japan, received an intriguing email... An amateur astronomer in his country had spotted a bright flash in Jupiter’s atmosphere. Dr. Arimatsu, who runs an  observation program  to study the outer solar system using backyard astronomy equipment, put out a call for more information. Six more reports of the Aug. 28 flash — which, according to Dr. Arimatsu, is one of the brightest ever recorded on the giant gas planet — came in from Japanese skywatchers. Flashes like these are caused by asteroids or comets from the edges of our solar system that impact Jupiter’s atmosphere. “Direct observation of these bodies is virtually impossible, ...,” Dr. Arimatsu wrote.... But Jupiter’s gravity lures in these objects, which eventually slam into the planet, “making it a unique and invaluable tool for studying them directl...

https://www.nytimes.com/2023/05/12/science/saturn-moons-jupiter.html By Jonathan O’Callaghan , The New York Times.  Excerpt: This month, the International Astronomical Union is set to recognize 62 additional  moons of Saturn  based on a batch of objects discovered by astronomers. The small objects will give Saturn 145 moons — eclipsing Jupiter’s total of 95. ...The growing number of moons also highlights potential debates over what constitutes a moon. “The simple definition of a moon is that it’s an object that orbits a planet,” Dr. Sheppard said. An object’s size, for the moment, doesn’t matter. ...In March, Dr. Sheppard was also responsible for finding  12 new moons of Jupiter , which took it temporarily above Saturn in the scuffle to be the biggest hoarder of moons. That record was short-lived, it seems....

https://www.nytimes.com/2023/02/16/science/auroras-jupiter-moons.html By Robin George Andrews , The New York Times.  Excerpt: New research shows auroras can also be seen on the Galilean moons of Jupiter:  hypervolcanic Io ,  icy Europa , quirky Callisto and  gigantic Ganymede . ...other than  Ganymede , the big moons of Jupiter lack magnetic bubbles. Instead, their auroras owe their existence to Io. Its noxious atmosphere — partly supplied by the moon’s  epic volcanic eruptions  — regularly sheds into space. The castoffs mingle with sunlight and become electrically excited. Plenty gets captured by  Jupiter’s colossal magnetic bubble , but some of it slams back into Io’s atmosphere, or into the other three moons’ gassy sheaths. Those impacts are what ignite the moons’ auroral lights....

https://skyandtelescope.org/astronomy-news/astronomers-find-a-dozen-more-moons-for-jupiter/ By Jeff Hecht, Sky & Telescope.  Excerpt: The biggest planet in the solar system now has the largest family of moons. Since December 20th, the Minor Planet Center (MPC) has published orbits for 12 previously unreported moons of Jupiter. More publications are expected, says Scott Sheppard (Carnegie Institute for Science), who recently submitted observations of the Jovian system taken between 2021 and 2022. The discoveries bring the list of Jovian moons to 92, a hefty 15% increase from the previous tally of 80. ...The new finds put Jupiter’s lunar family count well ahead of Saturn’s 83 confirmed moons. However, while Jupiter may have the most moons for now, Saturn might catch up. A search for objects with sizes down to about 3 kilometers across that are moving along with the gas giants  found three times more near Saturn than near Jupiter .... 

https://www.scientificamerican.com/article/the-best-of-jwsts-cosmic-portraits/ By Clara Moskowitz , Scientific American.  Excerpt: [Images Jupiter, Neptune and their rings as well as the phantom galaxy, M74.]

https://www.nytimes.com/2022/09/30/science/europa-nasa-juno-photos.html By  Kenneth Chang , The New York Times.  Excerpt: Juno, a NASA spacecraft that has been orbiting Jupiter since 2016, zipped within 219 miles of Europa’s surface early on Thursday, speeding by at more than 30,000 miles per hour. Less than 12 hours later, the four images taken during the flyby, the closest observations of the moon since January 2000, were back on Earth. “They’re stunning, actually,” said Candice J. Hansen-Koharcheck, a scientist at the Planetary Science Institute in Tucson, Ariz., who is responsible for the operation of the spacecraft’s primary camera,  JunoCam . ...All four images were available  on Juno’s website .… 

https://blogs.nasa.gov/webb/2022/08/22/webbs-jupiter-images-showcase-auroras-hazes/ By Alise Fisher , NASA Webb Space Telescope.  Excerpt: ...NASA’s James Webb Space Telescope has captured new images of [Jupiter].  ...“We hadn’t really expected it to be this good, to be honest,” said planetary astronomer Imke de Pater, professor emerita of the University of California, Berkeley. ...“It’s really remarkable that we can see details on Jupiter together with its rings, tiny satellites, and even galaxies in one image,” she said. The two images come from the observatory’s Near-Infrared Camera (NIRCam), which has three specialized infrared filters that showcase details of the planet. Since infrared light is invisible to the human eye, the light has been mapped onto the visible spectrum. Generally, the longest wavelengths appear redder and the shortest wavelengths are shown as more blue. Scientists collaborated with citizen scientist Judy Schmidt to translate ...

https://news.berkeley.edu/story_jump/jupiters-annual-portrait-is-a-beaut/ Source:   By Robert Sanders, UC Berkeley News. Excerpt: Just as families record the changing faces of their kids as they grow older, the Hubble Space Telescope each year captures the changing faces of the solar system’s four colorful gas-giant planets. The newest photo in that yearbook is a portrait of Jupiter taken June 27 that reveals clouds swirling in the planet’s turbulent atmosphere that are painted with a color palette more intense than seen in previous years. Mike Wong, an associate researcher in UC Berkeley’s Department of Astronomy and one of three members of the Hubble team taking the photos, was most intrigued by a mysterious color change around Jupiter’s equator: The formerly white equatorial belt has become orangish. And, surprisingly, Red Spot Jr., a planet that was red the last time it was photographed, has turned white. It is now back to the way it looked at its formation in 2000, before ...

• comparison image between Pioneer’s visit(s) and a more recent ground-based image - http://www.unmannedspaceflight.com/index.php?act=attach&type=post&id=21649 • HST images - http://hubblesite.org/image/3368/news/20-jupiter • animation of GRS shrunk another 20% or so - http://spaceweather.com/archive.php?view=1&day=08&month=06&year=2019 • Christopher Go - http://astro.christone.net/jupiter/ • Anthony Wesley (see 2019 Apr) - http://www.acquerra.com.au/astro/gallery/jupiter/ • Damian Peach (2019) - http://www.damianpeach.com/jupiter.htm

https://apnews.com/5604f183641342f1ad7f99f2ce665181 Source:   By Emiliano Rodriguez Mega, Associated Press. Excerpt: Astronomers are still finding moons at Jupiter, 400 years after Galileo used his spyglass to spot the first ones. The latest discovery of a dozen small moons brings the total to 79, the most of any planet in our solar system. Scientists were looking for objects on the fringes of the solar system last year when they pointed their telescopes close to Jupiter’s backyard, according to Scott Sheppard of the Carnegie Institute for Science in Washington. They saw a new group of objects moving around the giant gas planet but didn’t know whether they were moons or asteroids passing near Jupiter. ...The team is calling one of the new moons an ‘oddball’ because of its unusual orbit. Sheppard’s girlfriend came up with a name for it: Valetudo, the great-granddaughter of the Roman god Jupiter. Valetudo is in Jupiter’s distant, outer swarm of moons that circles in the opposite ...

http://www.sciencemag.org/news/2018/03/jupiter-s-chaotic-storms-have-roots-deep-beneath-its-surface Source:   By Paul Voosen, Science. Excerpt: The gaseous veil of Jupiter’s surface has long cast a pall over scientists’ quest to understand the giant planet’s depths. In particular, researchers have debated whether the bands of east-west winds ...extend deeper into the planet, or are merely superficial. Now, a series of papers from NASA’s Juno spacecraft, published today in Nature, has revealed that the roots of Jupiter’s winds indeed run deep. ...Juno’s scientists discovered an asymmetry in Jupiter’s north-south gravitational field that reflected shifting masses driven by rising winds from 3000 kilometers deep within the planet. These flows of hydrogen and helium, the team shows, are driven up by energy lost from the planet’s deeper interior, which rotates like a solid because of crushing high pressures....    See also Scientific American article: https://www.scientifi...

Source:   By Kenneth Chang, The New York Times 2017-07-12. . . For GSS A Changing Cosmos chapter 7. Excerpt: NASA’s Juno spacecraft has been making repeated swoops just above the cloud tops of Jupiter. During the latest flyby, on Monday, the spacecraft passed about 5,600 miles over the Great Red Spot, a 10,000-mile-wide storm that has swirled for at least 350 years. NASA posted images from the flyby on the web on Wednesday. ...“The more we zoom into the Great Red Spot, the more turbulent it seems to be,” said James O’Donoghue, another scientist at NASA Goddard. “In some of the processed images we can clearly see anticlockwise rotating cells within the giant storm itself — storms within storms.”.... https://www.nytimes.com/2017/07/12/science/jupiter-great-red-spot-nasa-juno.html

Source:   By Kenneth Chang, The New York Times Excerpt: The top and bottom of Jupiter are pockmarked with a chaotic mélange of swirls that are immense storms hundreds of miles across. The planet’s interior core appears bigger than expected, and swirling electric currents are generating surprisingly strong magnetic fields. Auroral lights shining in Jupiter’s polar regions seem to operate in a reverse way to those on Earth. And a belt of ammonia may be rising around the planet’s equator. Those are some early findings of scientists working on NASA’s Juno mission, an orbiter that arrived at Jupiter last July. Juno takes 53 days to loop around Jupiter in a highly elliptical orbit, but most of the data gathering occurs in two-hour bursts when it accelerates to 129,000 miles an hour and dives to within about 2,600 miles of the cloud tops. The spacecraft’s instruments peer far beneath, giving glimpses of the inside of the planet, the solar system’s largest. ...Planetary scientists had w...