Exploration of the gas giants

[weatheriscool]

Astronomers Found Something Cold and Wet Near Uranus
The icy moon Miranda is the latest satellite in our solar system to spark hope in the search for life beyond Earth.
By Isaac Schultz Published October 30, 2024 | Comments (0)
https://gizmodo.com/astronomers-found-s ... 2000518316

The Uranian moon Miranda may contain a liquid water ocean, according to a team of researchers that recently mapped the satellite’s surface and modeled tidal stress on it.

The team published its study earlier this month in The Planetary Science Journal, suggesting the “plausible existence” of an ocean at least 100 kilometers (62 miles) thick on Miranda within the past 100 to 500 million years. Though the researchers don’t think such a deep water body is still present, liquid water may remain under the moon’s surface, as one researcher told the Johns Hopkins Applied Physics Laboratory. If Miranda had frozen completely, the team believes there would be certain cracks on the moon’s surface—evidence of the frozen ocean’s expansion within. No such cracks are present, based on the researchers’ review of the available imagery.

[wjfox]

Astronomers Found Something Cold and Wet Near Uranus

[wjfox]

[weatheriscool]

Astronomers discover a new dense sub-Saturn exoplanet
https://phys.org/news/2025-01-astronome ... lanet.html
by Tomasz Nowakowski , Phys.org

An international team of astronomers has reported the detection of a new exoplanet orbiting a bright late F-type star. The newfound alien world, designated TOI-6038 A b, is about six times larger and nearly 80 times more massive than Earth. The finding is detailed in a paper published Jan. 4 on the arXiv preprint server .

NASA's Transiting Exoplanet Survey Satellite (TESS) is conducting a survey of about 200,000 of the brightest stars near the sun with the aim of searching for transiting exoplanets. So far, it has identified nearly 7,400 candidate exoplanets (TESS Objects of Interest, or TOI), of which 591 have been confirmed so far.

Now, a group of astronomers led by Sanjay Baliwal of the Physical Research Laboratory (PRL) in Ahmedabad, India, reports the confirmation of another planet monitored by TESS. Baliwal's team has identified a transit signal in the light curve of TOI-6038 A—a late F-type star about 578 light-years away. The planetary nature of this signal was validated by follow-up observations using the 2.5m telescope at the PRL Observatory in India.

"TOI-6038 A (TIC 194736418) was observed by TESS in Sectors 18 and 58. The Sector 18 (S18) observations were conducted between November 3 and November 27, 2019, while the Sector 58 (S58) observations took place from October 29 to November 26, 2022," the paper reads.

[weatheriscool]

Juno Probe Spots Largest Known Volcanic Event on Io
The Jovian moon Io has more than 400 active volcanoes, but the latest discovery is the largest of them all.
By Ryan Whitwam January 30, 2025
https://www.extremetech.com/science/jun ... vent-on-io

NASA's Juno spacecraft has been orbiting Jupiter for more than eight years, probing the solar system's largest planet with its suite of specialized instruments. The mission's extended mission has seen NASA turn its attention to Jupiter's moons, including the tumultuous world of Io, the most volcanically active location in the solar system. Even with that distinction, the team was shocked by the scale of Juno's latest discovery, which appears to be the most powerful volcanic event ever recorded.
Since completing its primary science objectives in orbit of Jupiter, Juno has been conducting flybys of the Jovian moons Io, Europa, Ganymede, and Callisto. The spacecraft completed two very close flybys in 2023 and 2024, passing within 930 miles (1,500 kilometers) of Io's surface. Its more recent visits have been at a much higher altitude of 46,200 miles (74,400 kilometers), but you don't need to be terribly close to see Io's megavolcano.

[wjfox]

[wjfox]

Astronomers discover 128 new moons orbiting Saturn

Tue 11 Mar 2025 20.27 GMT

Astronomers have discovered 128 new moons orbiting Saturn, giving it an insurmountable lead in the running tally of moons in the solar system.

Until recently, the “moon king” title was held by Jupiter, but Saturn now has a total of 274 moons, almost twice as many as all the other planets combined. The team behind the discoveries had previously identified 62 Saturnian moons using the Canada France Hawaii telescope and, having seen faint hints that there were more out there, made further observations in 2023.

“Sure enough, we found 128 new moons,” said the lead researcher, Dr Edward Ashton, a postdoctoral fellow in the Institute for Astronomy and Astrophysics at the Academia Sincia in Taiwan. “Based on our projections, I don’t think Jupiter will ever catch up.”

https://www.theguardian.com/science/202 ... ing-saturn

[weatheriscool]

[weatheriscool]

NASA's Nuclear-Powered 'Dragonfly' Rotorcraft Clears Critical Checkpoint
The trailblazing spacecraft is on track to fly to Saturn's moon Titan in 2028.
By Adrianna Nine April 29, 2025

Dragonfly, NASA's nuclear-powered rotorcraft-in-progress, has cleared a pivotal checkpoint, the agency announced Thursday. Dragonfly's critical design review—required for all of NASA's unmanned missions—involved a close inspection of the mission's design, fabrication, integration, and test plans, all of which were reportedly approved. Construction can now begin on the $3.35 billion project.

Dragonfly will explore a world largely untouched by Earthly science: Titan, Saturn's largest moon. The second-largest moon in the solar system (after Jupiter's Ganymede), Titan possesses a thick, stormy atmosphere, pools of liquid water, and even a key organic molecule, leading scientists to wonder whether it harbors simple forms of life. Because the Earth-like moon is so far away, however, only one spacecraft has ever landed on its surface. In 2005, the Huygens probe—part of NASA's Cassini-Huygens mission—touched down near Titan's Adiri region, which scientists think is covered with grains of sand made of ice.

https://www.extremetech.com/science/nas ... checkpoint

[weatheriscool]

Juno mission gets under Jupiter's and Io's surface
https://phys.org/news/2025-04-juno-miss ... rface.html
by DC Agle, Karen Fox, Molly Wasser and Deb Schmid, NASAthe spacecraft’s 69th flyby on Jan. 28, 2025.

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."

[wjfox]

Two new moons of Jupiter have been reported by the Minor Planet Center:

S/2017 J 10
S/2017 J 11

So its total count is now 97. Long way to go before it catches up with Saturn, though (which is currently at 274).

[weatheriscool]

[weatheriscool]

Saturn's Moon Titan Glows in Cloud-Bound Webb Images
The images are the first to capture the process of cloud convection on Titan, rather than the 'before' and 'after.'
By Adrianna Nine May 16, 2025

Titan, Saturn's largest moon and the second-largest in the solar system, is a strange place. Like Earth, it has lakes and seas; unlike on Earth, those bodies are filled with liquid methane. Titan also has seasonal weather—something all of us are familiar with here on Earth—tied to its surprisingly complex atmosphere. How the atmosphere shapes these weather patterns, though, has been a mystery since the atmosphere itself was discovered.

In an effort to untangle its meteorology, an international team of researchers pointed NASA's James Webb Space Telescope and WM Keck Observatory's twin telescopes at Titan in November 2022 and July 2023. The observations led not only to a series of mesmerizing images but also to a surprising discovery regarding Titan's atmosphere.

https://www.extremetech.com/science/sat ... ebb-images

[weatheriscool]

Jupiter Was Once Double Its Current Size
And far more magnetic, too.
By Adrianna Nine May 23, 2025

We humans might grow larger as we move from early life to adulthood, but Jupiter has done the opposite. New research offers a snapshot of what the gas giant would have looked like at the beginning, and it turns out Jupiter was once far larger—and more magnetic—than it is today.

Understanding how planets have evolved is key to projecting how the solar system, the galaxy, and the entire universe might morph over the next several million years. Scientists have a good idea of what early Mars was like, plus a smattering of details about the other planets in our celestial neighborhood. But as the first and biggest planet in our solar system, Jupiter has played a major role in shaping this little corner of space. Its gravitational pull is widely thought to have sculpted other planets' orbital paths, and it might have even helped sweep together the dust and gas necessary to form those planets in the first place.
An illustration of Jupiter with magnetic field lines emitting from its poles.

https://www.extremetech.com/science/jup ... rrent-size

[weatheriscool]

Jupiter's moon Europa has constantly changing ice surface, experiments suggest
https://phys.org/news/2025-05-jupiter-m ... y-ice.html
by Southwest Research Institute

A series of experiments led by Southwest Research Institute's Dr. Ujjwal Raut support spectral data recently collected by the James Webb Space Telescope (JWST) that found evidence that the icy surface of Jupiter's moon Europa is constantly changing. Europa's surface ice is crystallizing at different rates in different places, which could point to a complex mix of external processes and geologic activity affecting the surface.

Water ice can be divided into two broad categories based on its structure. On Earth, crystalline ice occurs when water molecules arrange into a hexagonal pattern during the freezing process. But on the surface of Europa, exposed water ice is constantly bombarded by charged particles that disrupt the crystalline structure, forming what is referred to as amorphous ice.

Raut, a program manager in SwRI's Planetary Science Section, co-wrote a paper outlining the findings from extensive laboratory experiments conducted by his team to understand Europa's icy surface. The paper is published in The Planetary Science Journal.

The experiments proved critical to constrain the time scales for the amorphization and recrystallization of ice on Europa, particularly in the chaos terrains where features such as ridges, cracks and plains are jumbled and enmeshed with one another. Combined with the new data collected by JWST, Raut said they are seeing increasing evidence for a liquid ocean beneath the icy surface.

[weatheriscool]

Shelved Europa Lander mission concept could be used to explore Enceladus instead

by Bob Yirka, Phys.org
https://phys.org/news/2025-06-shelved-e ... ncept.html
edited by Lisa Lock, reviewed by Robert Egan
Editors' notes

A team of engineers at NASA's Jet Propulsion Laboratory has outlined the decade-long development and testing of what was originally known as the Europa Lander prototype—a partially autonomous robot designed to find out if Jupiter's moon Europa harbors life beneath its icy surface.

In their paper published in the journal Science Robotics, the group describes the criteria they used in designing their robot, which would walk around on the surface of the moon, rather than roll, and drill down through its icy crust. They also share how it performed during testing in Alaska.

For many years, scientists at NASA have been investigating the possibility of sending a lander of some type to either Enceladus or Europa—both have icy crusts that cover a liquid-water ocean. The existence of water suggests the possibility of life.

But this would present some very steep challenges. They are much farther away than other places landers have been sent, which means it would take much longer to get there, as would communication signals. Also, they both are more highly exposed to radiation than Mars, though Europa is much more so than Enceladus—and both are extremely cold.

[caltrek]

"Potential Impact on Saturn": Astronomers Appeal for Help as Video Appears to Show Object Hitting the Gas Giant
By James Felton
July 7, 2025

Introduction:

(IFL Science) Astronomers at the Planetary Virtual Observatory and Laboratory (PVOL) are appealing for help, after an image taken by NASA's Mario Rana appears to show an object slamming into Saturn.

Saturn, like Jupiter, is a gas giant. With their impressive masses, you would expect these giants to attract their share of asteroid impacts. Unlike terrestrial planets, which are usually left with an obvious crater after impact, on gas giants, it is not entirely obvious. With outer layers primarily composed of hydrogen and helium, any trace of an impact can disappear.

Astronomers have attempted to model how many impacts take place on the gas giant. One recent study put the number of impacts by objects over 1 kilometer at around 3.2 × 10−3 yr−1 ( 0.0032 per year, or 1 every 3,125 years). Smaller impacts are thought to be more common, with Cassini data showing that impacts can leave telltale ripples in Saturn's rings.

"These new results imply the current-day impact rates for small particles at Saturn are about the same as those at Earth – two very different neighborhoods in our Solar System – and this is exciting to see," Linda Spilker, Cassini project scientist at NASA's Jet Propulsion Laboratory, explained in 2013. "It took Saturn's rings acting like a giant meteoroid detector – 100 times the surface area of the Earth – and Cassini's long-term tour of the Saturn system to address this question."

Despite these impacts being relatively common – around 8,000 meteorites impact Earth every year – we have never observed an object hitting Saturn. Until, just maybe, now. On Saturday, July 5, NASA's Mario Rana captured a potential impact, which has now been reported to the Planetary Virtual Observatory & Laboratory (PVOL).

Read more here: https://www.iflscience.com/potential-i ... nt-79901

[weatheriscool]

[weatheriscool]

Titan’s Hydrocarbon Seas Could Have the Conditions for Protocells, Study Shows
It’s not proof of life, but it is evidence that environments unlike Earth's could also give rise to life.
By Graham Templeton July 17, 2025

A new study conducted by NASA researchers proposes a novel mechanism of formation for protocell (thought to be the precursors to modern cells) constructs called vesicles.

Forming not in the water-seas of Earth but the hydrocarbon seas of Saturn's moon Titan, these vesicles would be just the first component in a possible first Titanian replicator—but other aspects of Titan’s environment could provide the rest.
Vesicles and Abiogenesis

A vesicle is just a membrane-bound sac. That’s it. Living animal and plant cells here on Earth use vesicles internally to transport materials, remove waste, and more; sometimes, they even eject vesicles to transfer materials between cells. On their own, vesicles are not that useful—but they could also be seen as the most primitive possible form of a cell membrane.

https://www.extremetech.com/science/tit ... ells-study

[weatheriscool]