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A seismic wave detected shortly before the Hunga Tonga-Hunga Ha’apai eruption in January 2022 could help scientists predict future volcanic activity in remote ocean areas. A study published by the American Geophysical Union suggests that the seismic wave, detected 750 kilometres from the volcano, was likely triggered by a rupture in the oceanic crust. This break allowed seawater to interact with magma near the volcano’s magma chamber, leading to the eruption. The research offers insight into early eruption indicators, which could be crucial for tsunami warning systems.

Precursor Signals Could Improve Tsunami Alerts

As per the study published, a Rayleigh wave was recorded at two distant seismic stations in Fiji and Futuna fifteen minutes before the January 15 eruption. It raised interest among researchers studying volcanic triggers. According to volcanologist Mie Ichihara from the University of Tokyo, the seismic activity likely indicated a significant fracture in the crust beneath the caldera. This allowed seawater and magma to mix, triggering a violent eruption. The event underlines the need for effective early-warning mechanisms for island nations vulnerable to volcanic eruptions and the tsunamis they can cause.

Analysing Seismic Activity for Predictive Insights

Takuro Horiuchi, the study’s lead author and a graduate researcher in volcanology at the University of Tokyo, notes that seismic waves often accompany volcanic eruptions, but these signals are typically subtle and limited to the immediate vicinity of the volcano. However, this particular seismic wave travelled hundreds of kilometres, indicating a major geological event prior to the eruption. Horiuchi and Ichihara believe the fracture process may have triggered extensive movement within the crust, ultimately leading to the explosive eruption.

Learning from Rare Caldera-forming Eruptions

The Hunga Tonga-Hunga Ha’apai eruption was unusual due to its underwater location and immense energy release. Ichihara points out that understanding the mechanisms behind such events is challenging because there are few documented instances of caldera-forming eruptions, particularly in oceanic environments. The seismic wave preceding the eruption presents one possible sequence of events, although Ichihara cautions that different processes may be involved in other cases.

Future Application in Disaster Preparedness

Ichihara suggests that detecting seismic signals from volcanic eruptions could give local observatories valuable preparation time. If future eruptions produce similar seismic signals, tsunami-prone regions may have more time to respond, providing a significant advantage for disaster preparedness in vulnerable areas.

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Webb Telescope Spots Possible Jellyfish Galaxy 12 Billion Light-Years Away

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Webb Telescope Spots Possible Jellyfish Galaxy 12 Billion Light-Years Away

Astronomers have discovered a new “jellyfish” galaxy about 12 billion light-years away using the James Webb Space Telescope. It appears to have tentacle-like streams of gas and stars trailing off one side, a signature feature of jellyfish galaxies. These galaxies develop such trails via ram pressure stripping as they move through dense cluster environments, triggering star formation in the stripped gas. The find was made by Ian Roberts of Waterloo University, and details are described in a preprint on arXiv. More analysis is needed to confirm the classification, but early signs strongly suggest this object is indeed a jellyfish galaxy.

What Are Jellyfish Galaxies?

According to NASA, jellyfish galaxies are so named because of the long, trailing streams of gas and young stars that extend from one side of the galaxy. This phenomenon occurs when a galaxy moves rapidly through the hot, dense gas in a cluster, and ram pressure strips material away. The stripped gas forms a wake behind the galaxy, and this wake often lights up with bursts of new star formation. At the same time, the process can deprive the galaxy’s core of gas, potentially slowing star formation in the galaxy’s center.

Because the jellyfish stage is short-lived on cosmic timescales, astronomers rarely catch galaxies in this act. Studying jellyfish galaxies gives scientists insight into how dense environments affect galaxy evolution and star formation.

Discovery and Future Research

The researchers caution that the galaxy’s apparent “tentacles” may partly be an artifact of the imaging method. If confirmed, this object (COSMOS2020-635829) would be the most distant known jellyfish galaxy, offering a rare glimpse of how ram pressure stripping and cluster-driven quenching operated in the early cosmos. As the study authors note, finding a jellyfish at z>1 reinforces the idea that these environmental effects were already at work near the peak of cosmic star formation.

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Mars Dust Devils May Spark Lightning, Might Pose Risks to Rovers: Study

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Mars Dust Devils May Spark Lightning, Might Pose Risks to Rovers: Study

Dust devils on Mars – swirling columns of dust and air that often scour the Red Planet’s surface – may be crackling with electricity, a new computer-modeling study suggests. Researchers led by Varun Sheel simulated how Mars’s dry atmosphere and frictional dust collisions charge up grains inside a vortex. They found these fields could grow so strong that brief lightning-like discharges might occur. This electrification is a concern for surface missions, since charged dust could cling to rover wheels, solar panels and antennas, blocking sunlight and interfering with communications.

Formation and Features of Martian Dust Devils

According to the study, dust devils form when the Sun heats Mars’s surface, causing warm air to rise and spin into vortices. Colder air rushes inward along the ground, stretching the rising column upward and whipping dust high into the sky. Because Mars has lower gravity and a thinner atmosphere than Earth, its dust devils can tower much higher, three times larger than storms on Earth. NASA’s Viking mission first detected Martian dust devils; later rovers like Curiosity and Perseverance have filmed them sweeping across the dusty plains. These whirlwinds clean off solar panels – as happened with Spirit in 2005 – but more often they stir up fine dust that can coat instruments.

Electrification and Risks to Rovers

Dust grains in Martian whirlwinds can pick up charge through collisions (a triboelectric effect). Sheel’s models predict that this charge separation can create strong electric fields inside a dust devil. These fields could even exceed Mars’s atmospheric breakdown threshold (around 25 kV/m), enough to spark lightning in the vortex. NASA’s Perseverance rover recorded what appears to be a small triboelectric discharge when a dust devil passed overhead.

Even without lightning, any static buildup is problematic. As planetary scientist Yoav Yair notes, “Electrified dust will adhere to conducting surfaces such as wheels, solar panels and antennas,” potentially reducing sunlight reaching panels and jamming communications. Rovers may need new design features or procedures to handle this unusual Martian weather.

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NASA’s Perseverance Grinds Into ‘Weird’ Martian Rock to Uncover Signs of Ancient Habitability

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NASA's Perseverance Grinds Into ‘Weird’ Martian Rock to Uncover Signs of Ancient Habitability

NASA’s Perseverance rover has begun drilling into a rock on Mars as it tries to collect more information about the Red Planet’s ancient environment. The Rover could help in finding the answers to the most-asked question: Mars was previously habitable. Previously, the rover abraded a spot called “Kenmore”, a rocky outcrop in Jezero Crater. The rover took away the outer layer, which exposed the unadulterated material below. This method, which involves mechanical grinding and puffs of nitrogen gas, allowed scientists to study rock interiors that have been protected from wind, radiation, and dust for billions of years. The mission represents a move from reconnoitering to examining, applying advanced technologies to detect stones of a bygone era, past water, and possibly life.

Perseverance Uncovers Water-Rich Minerals in Stubborn Mars Rock, Aiding Future Exploration Plans

As per a NASA report, the Kenmore rock proved unexpectedly difficult. “It vibrated all over the place, and small chunks broke off,” stated Ken Farley, Perseverance’s deputy project scientist. Despite the challenge, the team managed to expose enough of the surface for analysis. Instruments like WATSON and SuperCam revealed clay minerals—hydrated compounds containing iron and magnesium, suggesting prolonged water exposure. These findings align with Jezero Crater’s history as a river delta and lakebed, making it a prime site for biosignature exploration.

Additional SHERLOC and PIXL measurements verified the presence of feldspar and atomically dispersed manganese – a first for the Martian samples. Why they were important: They grew in water-rich environments, a hint that the red planet had a more watery past. The rover’s instruments will also be used to assess whether such rocks could be exploited in future human missions, extracting fuel or constructing habitats. “The data we’re getting now is what we’ll use to position ourselves so that future missions don’t land on uncooperative rocks,” Farley mentioned.

Kenmore is the 30th rock that Perseverance has examined up close, and the rover continues to drill and seal core samples that might someday be brought back to Earth. Yet the future of Mars Sample Return (MSR) overall is uncertain, with a proposed NASA budget for Fiscal Year (FY) 2026 under the Trump Administration cutting the campaign. All the same, the present mission still is serving up important bits of Mars’s geologic and possibly habitable past.

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