News Feeds

As the most volcanic object in the Solar System, Jupiter’s moon Io attracts a lot of attention. NASA’s Juno spacecraft arrived at the Jovian system in July 2016, and in recent months, it’s been paying closer attention to Io.

Though Io’s internal workings have been mostly inscrutable, images and data from Juno are starting to provide a fuller picture of the strange moon’s volcanic inner life.

Io’s extreme volcanic activity stems from tidal heating caused by massive Jupiter and its powerful gravity. Some of the moon’s volcanoes spew out plumes of sulphur and sulphur dioxide as high as 500 km (300 miles) above its surface. Sulphur is also ever-present in its lava flows, which colour the moon’s surface in various shades of yellow, red, white, green, and black. Some of the lava flows extend up to 500 km (300 miles) along its surface. These features entice scientists to study the moon more thoroughly.

One of Juno’s instruments is an imager and spectrometer that operates in the infrared. It’s called JIRAM (Jovian Infrared Auroral Mapper.) It was designed to, obviously, map Jupiter’s aurorae. But as Juno’s orbits have brought it progressively closer to Io, JIRAM is delivering high-quality images and data from the volcanic moon.

“The observations show fascinating new information on Io’s volcanic processes.”

Scott Bolton, Principal Investigator for Juno, SwRI

In new research in Nature Communications Earth and Environment, a team of scientists present some new insights into the moon and its vigorous volcanic activity. The title is “Hot rings on Io observed by Juno/JIRAM.” The lead author is Alessandro Mura from the National Institute of Astrophysics—Institute of Space Astrophysics and Planetology, Rome, Italy. Italy provided the JIRAM instrument for the Juno mission.

“We are just starting to wade into the JIRAM results from the close flybys of Io in December 2023 and February 2024,” said Scott Bolton, principal investigator for Juno at the Southwest Research Institute in San Antonio. “The observations show fascinating new information on Io’s volcanic processes. Combining these new results with Juno’s longer-term campaign to monitor and map the volcanoes on Io’s never-before-seen north and south poles, JIRAM is turning out to be one of the most valuable tools to learn how this tortured world works.”

Io has many of what planetary scientists call ‘paterae.’ Paterae are irregular craters or complex craters with scalloped edges. They’re usually broad and shallow, and scientists have wondered if they hold lava lakes. Older observations of Io from NASA’s Galileo spacecraft were inconclusive, but new images from Juno and JIRAM have much higher resolution.

In 2023, Juno came to within 13,000 km (8,100 miles) of Io’s surface, allowing JIRAM to capture greater detail. These images show more detail for a greater number of paterae, and the features the images reveal suggest that many of the craters have active lava lakes. “This new Juno/JIRAM data suggests that hot rings around paterae are a common phenomenon, and that they are indicative of active lava lakes,” the authors write in their paper.

This graphic shows the infrared radiance of Chors Patera, a lava lake on Jupiter’s moon Io. The white ring is the hottest part of the patera, between 232 and 732 Celsius, where lava from the moon’s interior is exposed. The red/green inside the ring is likely a thick crust of molten material that’s -43 Celsius. Outside the patera, the temperature is about -143 Celsius. Image Credit: NASA/JPL-Caltech/SwRI/ASI/INAF/JIRAM/MSSS

“The high spatial resolution of JIRAM’s infrared images, combined with the favorable position of Juno during the flybys, revealed that the whole surface of Io is covered by lava lakes contained in caldera-like features,” said Alessandro Mura, the paper’s lead author. “In the region of Io’s surface in which we have the most complete data, we estimate about 3% of it is covered by one of these molten lava lakes.”

Outstanding questions remain about the nature of Io’s volcanic activity and what happens underground. These new images help provide answers.

The lava lakes have only a thin ring of exposed lava. There are no lava flows beyond the rim or inside the rim, which indicates a balance between the magma that erupted into the lake and the magma that flowed back underground.

This figure from the research shows infrared radiance maps for six different paterae on Io. Each one has a lava ring inside the patera’s rim. Image Credit: Mura et al. 2024.

“We now have an idea of what is the most frequent type of volcanism on Io: enormous lakes of lava where magma goes up and down,” said Mura. “The lava crust is forced to break against the walls of the lake, forming the typical lava ring seen in Hawaiian lava lakes. The walls are likely hundreds of meters high, which explains why magma is generally not observed spilling out of the paterae and moving across the moon’s surface.”

The researchers proposed two different geologic models to explain the lava lakes in Io’s paterae: one they call a “central upwelling model” and the other a “piston motion” model.

The central upwelling model explains that the insulating crust “spreads radially via convection processes in the lake and then sinks at the edges, exposing lava,” the authors explain in their research. Basically, heat rises in the patera’s center, pushes outward radially, and hot lava founders at the edge and is exposed.

The problem with that model is the uniformity of the magma crust. JIRAM’s images show uniform heat across the magma crust, meaning it would have to be the same thickness. How could it maintain the same thickness while radiating horizontally?

The piston motion is slightly different. In that model, “a simple up-and-down ‘piston-type’ movement of the entire lake surface may cause disruption of the lava lake crust against the patera walls to reveal hotter material,” the authors explain. There’s no radiating horizontal motion like the central upwelling; rather, the entire lake moves up and down.

That model has problems, too. “For the piston-type lake model, the consistency between individual patera as well as the uniform brightness around the lake perimeter also poses geological challenges,” the authors explain. For all of the ten patera in the study to have hot rings of exposed lava, the vertical motion must be ongoing at all sites. At some sites, JIRAM should’ve detected changes in the depths of the patera. “No such depth changes at a specific patera have been reported,” the authors note, while also writing that the images may lack the temporal and spatial resolution to detect depth changes.

This figure from the research shows the two models the researchers are proposing. On the left in A and B is the central upwelling model. On the right in C and D is the piston motion model. Image Credit: Mura et al. 2024.

Activity at the rim where the lava is hottest may hold the eventual answer. “The observation of activity at the borders of the lake raises the question of whether some type of thermal or mechanical erosion between the lake surface and the patera walls might be taking place,” the authors write. Paterae might grow larger over time, but only by as much as a few hundred meters each year. No changes have been noted between visits by Voyager, Galileo, and Juno. It’s still possible, but the data is inconclusive.

The Juno spacecraft may still be able to provide deeper answers to Io’s volcanic activity. It’s already completed closer flybys of Io, and that data will be available in the future.

“Once the last Juno data are acquired, examining visible images of inactive patera for signs of former lava lake activity would be instructive,” the authors write in their conclusion.

The post Volcanic Plumes Rise Above Lava Lakes on Io in this Juno Image appeared first on Universe Today.

Researchers have sent data at a record rate of 402 terabits per second using commercially available optical fiber. This beats their previous record, announced in March 2024, of 301 terabits or 301,000,000 megabits per second using a single, standard optical fiber.

Researchers have sent data at a record rate of 402 terabits per second using commercially available optical fiber. This beats their previous record, announced in March 2024, of 301 terabits or 301,000,000 megabits per second using a single, standard optical fiber.

A new computational microscopy technique solves for true high-resolution images without the guesswork that has limited the precision of other techniques.

A new computational microscopy technique solves for true high-resolution images without the guesswork that has limited the precision of other techniques.

Protecting the astronauts of the Artemis program is one of NASA’s highest priorities. The agency intends to have a long-term presence on the Moon, which means long-term exposure to dangerous radiation levels. As part of the development of the Artemis program, NASA also set limits to the radiation exposure that astronauts can suffer. Other hazards abound on the lunar surface, including a potential micrometeoroid strike, which could cause catastrophic damage to mission equipment or personnel. NASA built a team to design and develop a “Lunar Safe Haven” to protect from these hazards. Their working paper was released in 2022 but still stands as NASA’s best approach to long-term living on the lunar surface.

The two hazards mentioned above provided the primary impetus for the design, but there are some nuances to them—in particular, radiation. Astronauts will experience two main types of hazardous radiation on the lunar surface: cosmic rays and solar eruptions. 

Cosmic rays are the more insidious of the two. They have a high energy range, so a shielding material that might work well for higher-energy particles might not do so for lower-energy ones. Moreover, some high-energy particles can interact with shielding, causing even more damaging radiation further down its path. Essentially, this increases the radiation risk inside the shielding compared to outside. The order in which the radiative particles are dealt with is one of the critical design considerations for dealing with this dangerous phenomenon. 

Lunar regolith can be hard to deal with, as Fraser discusses with Dr. Kevin Cannon.

However, solar particle events (SPEs) are the more overtly dangerous of the two types of radiation. While rare, they can cause acute radiation sickness. Current astronauts must shelter in place inside a protected chamber on the ISS when these happen, and building something equivalent on the surface of the Moon is a necessity to ensure that astronauts don’t simply die of acute radiation poisoning within the first six months of arrival.

With the problems to solve firmly in hand, the design team moved on to other considerations—like what the habitat inside the LSH would actually look like and how it would be built. Consideration of the habitat shape focused on one primary distinction—should the habitat be horizontal or vertical? The answer is vertical based on modeling the risk of radiation and micrometeoroid strikes.

So, how do you build a structure around a vertical habitat on the Moon? You employ robots and remotely operated construction equipment. Other groups at NASA had been working on solutions like the Lightweight Surface Manipulation System (LSMS), essentially a large crane that can be constructed in lunar gravity, and the Lunar Attachment Node for Construction and Excavation (LANCE) – a bulldozer module designed to attach to the front of NASA’s Chariot exploration vehicle. Utilizing these ideas and other construction ideas, it’s possible to construct a protective dome of lunar regolith around a long-term habitat for the Artemis missions. 

Fraser overviews the Artemis mission that LSH will attempt to help.

Such a protective habitat has significant advantages over digging one into the ground, which requires moving a massive amount of regolith or utilizing lava tubes with indeterminate structural integrity. But that means the LSH must have an above-ground design. The team developed two separate design ideas – a parabolic arch and a “Round Cake” design using polyethylene. The first is self-explanatory, but the second looks more like a typical cylinder with the radiation and micrometeoroid-blocking polyethylene stored in “beans” at the top of the structure. This could be made of waste materials from the mission, such as discarded food packaging.

Each design has advantages and disadvantages, and the team didn’t pick a final one as part of the paper. However, they did come up with a five-phase development process, from preparing the site in advance to living in interconnected habitats surrounded by regolith and protective shielding. Depending on the amount of automation involved and some real luck, those development phases could take anywhere from a few years to a few decades. 

It remains to be seen if this system will be adopted as an official part of the Artemis program. But it serves a need of critical importance to humanity’s long-term existence on the Moon. If that is indeed NASA’s goal for the end of the 2030s, it would be good to consider how to start making the LSH a reality.

Learn More:
Wok et al. – Design Analysis for Lunar Safe Haven Concepts
Moses & Grande – Lunar Safe Haven Seedling Study
UT – What Could We Build With Lunar Regolith?
UT – There are Four Ways to Build with Regolith on the Moon

Lead Image:
Artist’s depiction of the Parabolic Arc LSH in cutaway.
Credit – Wok et al.

The post Could A Mound of Dust and Rock Protect Astronauts from Deadly Radiation? appeared first on Universe Today.

Here, just posted, is a speech Biden gave today, after last night’s debate debacle.  It’s terrific, passionate, and not doddering at all.  Are there two Joe Bidens? Does he have a Doppelgänger?

Maybe he was nervous last night.

With lunar exploration ramping up, NASA has been tasked with defining a time zone for the moon. New calculations show that time is ever so slightly faster on the lunar surface, which can affect navigation

Two major US healthcare organisations have offered contradictory advice about the use of weight loss drugs in adolescents with obesity, underscoring just how little we know about the effects of these medications

A recent discovery by NASA's James Webb Space Telescope (JWST) confirmed that luminous, very red objects previously detected in the early universe upend conventional thinking about the origins and evolution of galaxies and their supermassive black holes.

A team of researchers has developed a soft, stretchy electronic device capable of simulating the feeling of pressure or vibration when worn on the skin. This device represents a step towards creating haptic technologies that can reproduce a more varied and realistic range of touch sensations for applications such as virtual reality, medical prosthetics and wearable technology.

A team of researchers has developed a soft, stretchy electronic device capable of simulating the feeling of pressure or vibration when worn on the skin. This device represents a step towards creating haptic technologies that can reproduce a more varied and realistic range of touch sensations for applications such as virtual reality, medical prosthetics and wearable technology.

Researchers have developed a novel deep learning algorithm that outperformed existing computer-based osteoporosis risk prediction methods, potentially leading to earlier diagnoses and better outcomes for patients with osteoporosis risk.

Researchers developed a new wireless receiver that can block strong interference signals at the earliest opportunity, which could improve the performance of a mobile device.

Researchers developed a new wireless receiver that can block strong interference signals at the earliest opportunity, which could improve the performance of a mobile device.

Researchers have found that artificial intelligence models that are most accurate at predicting race and gender from X-ray images also show the biggest 'fairness gaps' -- that is, discrepancies in their ability to accurately diagnose images of people of different races or genders.

Computer scientists have written a network flow algorithm that computes almost as fast as is mathematically possible. This algorithm computes the maximum traffic flow with minimum transport costs for any type of network. It thus solves a key question in theoretical computer science. The superfast algorithm also lays the foundation for efficiently computing very large and dynamically changing networks in the future.

Bringing us one step closer to solving the 'missing satellites problem,' researchers have discovered two new satellite galaxies.

Researchers have made a significant breakthrough by discovering that the drug 4-OI can enhance the effectiveness of a cancer-fighting viral agent. This may lead to treatment of cancers that are otherwise resistant to therapies.

An international team of researchers combine orbital imagery with seismological data from NASA's Mars InSight lander to derive a new impact rate for meteorite strikes on Mars. Seismology also offers a new tool for determining the density of Mars' craters and the age of different regions of a planet.