CHEOPS detects a new planetary "disorder"

Artist impression of the planetary system around the star LHS 1903
Image Credit: © ESA

Scientific Frontline: "At a Glance" Summary

• Main Discovery: Identification of LHS 1903 e, a rocky planet located beyond gas giants in the LHS 1903 system, contradicting the standard inner-rocky/outer-gas planetary hierarchy.
• Methodology: Utilized high-precision photometry from the ESA CHEOPS satellite to detect the planet, followed by planetary formation simulations to confirm an "inside-out" formation sequence and exclude migration or collision hypotheses.
• Key Data: Located 116 light-years from Earth around an M-type red dwarf; the fourth planet shares a similar mass with the inner third planet (a gas giant) yet possesses a rocky composition.
• Significance: Provides observational evidence for the inside-out planet formation theory, indicating that planets can form sequentially after the dissipation of protoplanetary disk gas rather than simultaneously.
• Future Application: Refinement of planetary accretion simulations to incorporate asynchronous formation timelines and better characterization of atypical planetary system architectures.
• Branch of Science: Astrophysics and Exoplanetology
• Additional Detail: Analysis indicates LHS 1903 e formed significantly later than its gas giant siblings, occurring only after the protoplanetary disk had been depleted of gas.

Hydrogen sulfide detected in distant gas giant exoplanets for the first time

This animation shows the four giant planets orbiting HR 8799, located 133 light-years from Earth. The movie combines real images captured at the W.M. Keck Observatory between 2009 and 2021, with the planets’ orbital motion smoothed by modeling their orbital paths around the star.
Image Credit: W. Thompson (NRC-HAA), C. Marois (NRC-HAA), Q. Konopacky (UCSD) 

Scientific Frontline: "At a Glance" Summary

• Main Discovery: Astronomers detected hydrogen sulfide molecules for the first time in the atmospheres of four massive gas giant exoplanets orbiting the star HR 8799.
• Methodology: Researchers utilized spectral data from the James Webb Space Telescope (JWST), applying new data analysis algorithms to suppress starlight and creating specialized atmospheric models to identify the unique light absorption signatures of sulfur.
• Key Data: The target system is located 133 light-years away in the constellation Pegasus, with the observed planets ranging from 5 to 10 times the mass of Jupiter and orbiting at distances greater than 15 astronomical units from their host star.
• Significance: The presence of sulfur indicates these bodies formed by accreting solid particles from a protoplanetary disk rather than collapsing directly from gas, definitively classifying them as planets rather than brown dwarfs.
• Future Application: The signal processing techniques developed for this study establish a viable method for characterizing the atmospheres of smaller, rocky worlds and searching for biosignatures on Earth-like exoplanets in the future.
• Branch of Science: Astronomy, Astrophysics and Planetary Science.
• Additional Detail: The study reveals that these distant giants share a heavy element enrichment pattern similar to Jupiter and Saturn, suggesting a universal formation mechanism for gas giants across different stellar systems.

NASA’s Juno spacecraft measures thickness of Europa’s ice shell

NASA’s Juno mission, led by an SwRI scientist, recently provided the first resolved subsurface measurements of the ice-encased Jovian moon Europa. This cutaway illustration shows an 18-mile-thick shell with a shallow layer containing small imperfections — cracks, pores and voids. The icy moon is thought to harbor a vast ocean beneath its icy exterior that could contain the ingredients for life.
Image Credit: NASA/JPL-Caltech/SwRI/K. Kuramura

Scientific Frontline: "At a Glance" Summary

• Main Discovery: Data from NASA’s Juno spacecraft reveals that the rigid, conductive outer ice shell of Jupiter’s moon Europa is approximately 29 kilometers thick.
• Methodology: Researchers utilized the Microwave Radiometer (MWR) instrument aboard Juno to measure thermal emissions and probe the ice shell at varying depths during a close flyby in September 2022.
• Key Data: The estimated thickness of the conductive ice layer is 29 ± 10 kilometers, though this figure could be reduced by approximately 5 kilometers if the ice contains significant salt levels.
• Significance: A shell of this thickness creates a substantial barrier to the transport of oxidants and nutrients from the surface to the subsurface ocean, potentially limiting the moon's habitability.
• Future Application: These findings characterize the ice shell properties to refine observation strategies for the upcoming Europa Clipper mission, particularly for calibrating its ice-penetrating radar.
• Branch of Science: Planetary Science and Astrobiology.
• Additional Detail: The MWR instrument detected shallow structural irregularities such as cracks and voids within the top hundreds of meters, but these features likely do not extend deep enough to serve as conduits for material exchange.Scientific Frontline: "At a Glance" Summary

Streaks on Mercury show: Mercury is not a "dead planet"

Image of the streaks or ‘lineae’ on the slopes of a crater wall on Mercury and the bright hollows from which the streaks originate. The image was taken by MESSENGER on April 10, 2014.
Image Credit: © NASA/JHUAPL/Carnegie Institution of Washington

Scientific Frontline: "At a Glance" Summary

• Main Discovery: A systematic analysis has identified approximately 400 bright slope streaks, or "lineae," on Mercury, indicating the planet is currently geologically active through the outgassing of subsurface volatiles.
• Methodology: Researchers employed a deep learning algorithm to automatically screen and analyze over 100,000 high-resolution images captured by NASA's MESSENGER spacecraft during its 2011–2015 orbital mission.
• Key Data: The study produced the first comprehensive census of roughly 400 streaks—compared to only a handful previously known—revealing a distinct accumulation on the sun-facing slopes of young impact craters.
• Significance: These findings overturn the prevailing assumption that Mercury is a "dead" and static world, suggesting a continuous, solar-driven release of elements like sulfur into space.
• Future Application: This inventory will serve as a baseline for the ESA/JAXA BepiColombo mission to re-image these regions, allowing scientists to detect new streak formation and quantify the planet's volatile budget.
• Branch of Science: Planetary Geology and Remote Sensing.
• Additional Detail: The formation of these streaks is attributed to solar radiation mobilizing volatiles through crack networks created by impact events, often originating from bright, shallow depressions known as hollows.

International astronomical survey captures remarkable images of the “teenage years” of new worlds

This ARKS gallery of faint debris disks reveals details about their shape: belts with multiple rings, wide smooth halos, sharp edges, and unexpected arcs and clumps, which hint at the presence of planets shaping these disks; and chemical make-up: the amber colors highlight the location and abundance of the dust in the 24 disks surveyed, while the blue their carbon monoxide gas location and abundance in the six gas-rich disks.
Image Credit: Sebastian Marino, Sorcha Mac Manamon, and the ARKS collaboration

Scientific Frontline: Extended "At a Glance" Summary

The Core Concept: The ARKS (ALMA survey to Resolve exoKuiper belt Substructures) program is an international astronomical survey that has captured the first high-resolution images of debris disks, which represent the chaotic "teenage" phase of planetary system evolution.

Key Distinction/Mechanism: Unlike the bright, gas-rich disks of newborn planets ("baby pictures"), these "teenage" systems are fainter dusty belts that exist after planets have formed but before the system settles into adulthood; the survey utilizes the Atacama Large Millimeter/submillimeter Array (ALMA) to resolve minute details like dust grains and carbon monoxide gas, revealing complex substructures rather than simple, uniform rings.

Origin/History: The survey team, led by the University of Exeter, secured approximately 300 hours of observation time at the ALMA observatory between October 2022 and July 2024, with findings published in a series of papers in Astronomy & Astrophysics.

Polar weather on Jupiter and Saturn hints at the planets’ interior details

This infrared 3D image of Jupiter's north pole shows a ring of 8 vortices surrounding a central cyclone. MIT researchers have now identified a mechanism that determines whether a gas giant evolves one versus multiple polar vortices.
Image Credit: NASA/JPL-Caltech/SwRI/ASI/INAF/JIRAM
(CC BY-NC-ND 4.0)

Scientific Frontline: "At a Glance" Summary

• Main Discovery: MIT researchers determined that the divergence in polar vortex patterns between Jupiter and Saturn—multiple smaller vortices versus a single massive one—is governed by the "softness" of the vortex's base, a property directly linked to the planet's interior composition.
• Methodology: The team utilized a two-dimensional model of surface fluid dynamics, adapting equations used for Earth's midlatitude cyclones to gas giant polar regions; they simulated vortex evolution from random fluid noise under varying parameters of size, rotation, heating, and fluid softness.
• Key Data: Simulations indicate that "softer" bases limit vortex growth, resulting in Jupiter's cluster of 3,000-mile-wide vortices, whereas "harder" bases allow expansion into a single, planetary-scale system like Saturn's 18,000-mile-wide hexagonal vortex.
• Significance: This study establishes a novel theoretical link between observable surface atmospheric patterns and hidden interior properties, suggesting Saturn possesses a denser, more metal-enriched interior compared to Jupiter's lighter, less stratified composition.
• Future Application: These findings provide a non-invasive framework for astrophysicists to infer the internal stratification and composition of gas giants solely by analyzing their surface fluid dynamics.
• Branch of Science: Planetary Science and Atmospheric Physics.
• Additional Detail: The researchers successfully reduced a complex 3D dynamical problem to a 2D model because the rapid rotation of gas giants enforces uniform fluid motion along the rotating axis.

Hidden magma oceans could shield rocky exoplanets from harmful radiation

UNDER ARMOR?
Deep layers of molten rock inside some super-earths could generate powerful magnetic fields—potentially stronger than Earth’s—and help shield these exoplanets from harmful radiation.
Illustration Credit: University of Rochester Laboratory for Laser Energetics  / Michael Franchot

Scientific Frontline: "At a Glance" Summary

• Main Discovery: Deep layers of molten rock known as basal magma oceans (BMOs) within super-earths become electrically conductive under extreme pressure, creating a dynamo capable of generating magnetic fields.
• Methodology: Researchers utilized laser shock compression experiments to replicate high-pressure planetary interiors, integrated with quantum mechanical calculations and planetary thermal evolution models.
• Key Data: Super-earths exceeding three to six times Earth's size can sustain these silicate-based dynamos for billions of years, potentially producing magnetic fields stronger than Earth's.
• Significance: This finding challenges the assumption that planetary magnetic fields require liquid metal cores, thereby expanding the definition of habitable zones to include massive rocky worlds previously thought to be unshielded from cosmic radiation.
• Future Application: Astronomers can apply these models to interpret future observations of exoplanet magnetic fields and atmospheric retention, refining the selection of targets for biosignature searches.
• Branch of Science: Planetary Science and High-Energy Density Physics

Tiny Mars’ big impact on Earth’s climate

Differences in the way Earth and Mars orbit the sun.
Image Credit: NASA

Scientific Frontline: "At a Glance" Summary

• Main Discovery: New simulations reveal that Mars exerts a definitive gravitational influence on Earth’s long-term climate patterns and ice ages, significantly shaping the orbital cycles that drive glacial periods.
• Methodology: Researchers utilized advanced computer models to simulate solar system dynamics over millions of years, isolating Mars' specific impact by observing Earth's orbital variations (Milankovitch cycles) with the Red Planet both present and theoretically removed.
• Specific Data: While the 430,000-year cycle driven by Venus and Jupiter remained stable in Mars-free simulations, the 100,000-year and 2.3 million-year climate cycles disappeared entirely without Mars' gravitational pull.
• Mechanism & Dynamics: The study demonstrated that increasing the mass of Mars in simulations stabilized Earth's axial tilt (obliquity) by reducing its rate of change, while simultaneously shortening the duration of specific orbital cycles.
• Implication for Exoplanets: These findings suggest that small, outer-orbit planets may be critical for maintaining the climatic stability of Earth-sized worlds in the habitable zones of other solar systems.

Mars was half covered by an ocean

The delta deposits that appeared on the images of Mars with the coastline.
Image Credit: © ESA/ExoMars – TGO/CaSSIS/Ignatius Argadestya

Scientific Frontline: "At a Glance" Summary

• Main Discovery: Analysis of geomorphologic structures in the Valles Marineris region confirms Mars hosted a vast ocean approximately three billion years ago.
• Specific Detail: Researchers identified "scarp-fronted deposits" in the southeast Coprates Chasma that function as fan deltas, marking the precise locations where ancient rivers deposited sediment into a standing body of water.
• Key Statistic: Reconstructed sea levels indicate this ancient ocean was at least as large as Earth's Arctic Ocean and extended across the planet's northern hemisphere.
• Methodology: The study utilized high-resolution imagery from the CaSSIS camera on the ExoMars Trace Gas Orbiter to map terrain features and apply terrestrial sedimentological models to Martian geology.
• Significance: The confirmation of extensive river deltas and a stable coastline provides strong evidence for a humid, "blue planet" environment that could have supported the emergence of life.
• Context: Although the delta structures are currently covered by wind-sculpted dunes, their preserved morphologies remain distinct enough to validate the presence of a historic coastline.

This exotic form of ice just got weirder

Researchers paired ultrafast X-rays with specialized instruments to study the atomic stacking structures of superionic water – a hot, black and strangely conductive form of ice that is believed to exist in the center of giant ice planets like Neptune and Uranus.
Illustration Credit: Greg Stewart/SLAC National Accelerator Laboratory

Researchers hoped to clarify the boundaries between different types of superionic water – the hot, black ice believed to exist at the core of giant ice planets. Instead, they found multiple atomic stacking patterns coexisting in overlapping configurations never seen before in this phase of water. 

Superionic water – the hot, black and strangely conductive form of ice that exists in the center of distant planets – was predicted in the 1980s and first recreated in a laboratory in 2018. With each closer look, it continues to surprise researchers.

In a recent study published in Nature Communications, a team including researchers at the Department of Energy’s SLAC National Accelerator Laboratory made a surprising discovery: Multiple atomic packing structures can coexist under identical conditions in superionic water.

We finally know how the most common types of planets are created

Astronomers have now witnessed four baby planets in the V1298 Tau system in the process of becoming super-Earths and sub-Neptunes.
Image Credit: Astrobiology Center, NINS  

Thanks to the discovery of thousands of exoplanets to date, we know that planets bigger than Earth but smaller than Neptune orbit most stars. Oddly, our sun lacks such a planet. That’s been a source of frustration for planetary scientists, who can’t study them in as much detail as they’d like, leaving one big question: How did these planets form? 

Now we know the answer. 

An international team of astrophysicists from UCLA and elsewhere has witnessed four baby planets in the V1298 Tau system in the process of becoming super-Earths and sub-Neptunes. The findings are published in the journal Nature. 

“I’m reminded of the famous ‘Lucy’ fossil, one of our hominid ancestors that lived 3 million years ago and was one of the ‘missing links’ between apes and humans,” said UCLA professor of physics and astronomy and second author Erik Petigura. “V1298 Tau is a critical link between the star- and planet-forming nebulae we see all over the sky, and the mature planetary systems that we have now discovered by the thousands.”

A new study finds Jupiter’s moon Europa’s quiet seafloor may still hold keys for life

A “black smoker” at the Piccard hydrothermal field, 5,000 meters below the surface, on the Mid-Cayman Rise.
Photo Credit: Chris German / ROV Jason, ©WHOI, 2012

The giant planet Jupiter has nearly 100 known moons, but none have captured the imagination of scientists quite like Europa. Scientists suspect Europa has a salty ocean beneath its icy crust, holding twice as much water as all of Earth's oceans combined. For decades, scientists have wondered whether that ocean could harbor the right conditions for life, placing Europa near the top of the list of solar system bodies to explore.

A new study,  led by Washington University and involving Woods Hole Oceanographic Institution (WHOI), indicates it may lack modern-day tectonic activity at the seafloor that sheds new light on this topic. Using models that account for Europa’s size, rocky core, and Jupiter’s gravity, the team concludes that the moon likely lacks the tectonic activity, or seafloor volcanism, that gives rise to dramatic “black smoker” hot springs on Earth.

Planetary Science: In-Depth Description

Image Credit: Scientific Frontline / AI generated (Gemini)

Planetary Science is the cross-disciplinary scientific study of planets, moons, and planetary systems—including our Solar System and those orbiting other stars—aiming to understand their formation, evolution, and current physical and chemical states. By integrating principles from astronomy, geology, atmospheric science, and physics, planetary science seeks to decipher the history of matter in the solar neighborhood and determine the potential for habitability beyond Earth.

SwRI may have solved a mystery surrounding Uranus’ radiation belts

SwRI scientists compared space weather impacts of a fast solar wind structure (first panel) driving an intense solar storm at Earth in 2019 (second panel) with conditions observed at Uranus by Voyager 2 in 1986 (third panel) to potentially solve a 39-year-old mystery about the extreme radiation belts found. The "chorus wave" is a type of electromagnetic emission that may accelerate electrons and could have resulted from the solar storm.
Image Credit: Southwest Research Institute

Southwest Research Institute (SwRI) scientists believe they may have resolved a 39-year-old mystery about the radiation belts around Uranus. 

In 1986, when Voyager 2 made the first and only flyby of Uranus, it measured a surprisingly strong electron radiation belt at significantly higher levels than anticipated. Based on extrapolations from other planetary systems, Uranus’ electron radiation belt was off the charts. Since then, scientists have wondered how the Uranian system could support such an intense trapped electron radiation belt, at a planet unlike anything else in the solar system. 

Findings suggest red planet was warmer, wetter millions of years ago

Purdue University research into scattered kaolinite rocks on Mars’ surface shows the dry, dusty planet could have featured a rain-heavy climate billions of years ago.
Photo Credit: NASA

Rocks that stood out as light-colored dots on the reddish-orange surface of Mars now are the latest evidence that areas of the small planet may have once supported wet oases with humid climates and heavy rainfall comparable to tropical climates on Earth.

The rocks discovered by NASA’s Perseverance Mars rover are white, aluminum-rich kaolinite clay, which forms on Earth after rocks and sediment are leached of all other minerals by millions of years of a wet, rainy climate.

These findings were published in the peer-reviewed scientific journal Communications Earth & Environment by lead author Adrian Broz, a Purdue University postdoctoral research associate in the lab of Briony Horgan, a long-term planner on NASA’s Mars Perseverance rover mission and professor of planetary science in the Department of Earth, Atmospheric, and Planetary Sciences in Purdue’s College of Science.

New SwRI laboratory to study the origins of planetary systems

Southwest Research Institute (SwRI) has created a new space science laboratory, the Nebular Origins of the Universe Research (NOUR) Laboratory. Led by SwRI Senior Research Scientist Dr. Danna Qasim, the NOUR laboratory aims to bridge pre-planetary and planetary science to create a better understanding of the origins of our universe.
Photo Credit: Southwest Research Institute

The laboratory will trace the chemical origins of planetary systems. Qasim aims to establish a robust astrochemistry program within SwRI’s Space Science Division, connecting early cosmic chemistry to planetary evolution. The SwRI lab will give particular focus on the chemistry of interstellar clouds, vast regions of ice, gas and dust between stars representing a largely unexplored area of astrochemistry.

“We are examining the chemistry of ice, gas and dust that have existed since before our solar system formed, connecting the dots to determine how materials in those clouds ultimately evolve into planets,” Qasim said. “By simulating the physico-chemical conditions of these pre-planetary environments, we can fill key data gaps, providing insights that future NASA missions need to accomplish their goals.”

Helium leak on the exoplanet WASP-107b

Artist's view of WASP-107b. The planet’s low density and the intense irradiation from its star allow helium to escape the planet and form an asymmetric extended and diffuse envelope around it.
Image Credit: © University of Geneva/NCCR PlanetS/Thibaut Roger

An international team including UNIGE observed with the JWST huge clouds of helium escaping from the exoplanet Wasp-107b. 

An international team, including astronomers from the University of Geneva (UNIGE) and the National Centre of Competence in Research PlanetS, has observed giant clouds of helium escaping from the exoplanet WASP-107b. Obtained with the James Webb Space Telescope, these observations were modeled using tools developed at UNIGE. Their analysis, published in the journal Nature Astronomy, provides valuable clues for understanding this atmospheric escape phenomenon, which influences the evolution of exoplanets and shapes some of their characteristics. 

Sometimes a planet’s atmosphere escapes into space. This is the case for Earth, which irreversibly loses a little over 3 kg of matter (mainly hydrogen) every second. This process, called ‘‘atmospheric escape’’, is of particular interest to astronomers for the study of exoplanets located very close to their star, which, heated to extreme temperatures, are precisely subject to this phenomenon. It plays a major role in their evolution. 

New observations suggest Mars’ south pole lacks lake beneath the ice

An artist's concept of NASA’s Mars Reconnaissance Orbiter, which has been orbiting the Red Planet since 2006. The antenna is part of SHARAD, a radar that peers below the Martian surface.
Image Credit: NASA/JPL-Caltech

A new study published in Geophysical Research Letters casts doubt on a 2018 discovery of a briny lake potentially lurking beneath Mars’ south polar cap.

SHARAD, the Shallow Radar sounder on NASA’s Mars Reconnaissance Orbiter (MRO), performed a maneuver that allowed it to peer deeper beneath the polar ice than ever before. It recorded only a faint signal where MARSIS (Mars Advanced Radar for Subsurface and Ionosphere Sounding), the low-frequency radar on the European Space Agency’s Mars Express spacecraft, found a highly radar-reflective surface under the ice in 2018, which that team interpreted to be due to the presence of liquid water.

“The existence of liquid water under the south pole is really compelling and exciting, but if it is there, SHARAD should also see a very bright reflectance spot, and we don’t,” said study lead author Gareth Morgan, a SHARAD co-investigator and Planetary Science Institute senior scientist.

Destination: Mars. First Stop: Iceland?

This picturesque vista is the watershed in southwest Iceland, where researchers collected mars rock analog samples.
Image Credit: Michael Thorpe/NASA Goddard

To say that a trip from Earth to Mars is merely a long one would be a massive understatement. On July 30, 2020, when the National Aeronautics and Space Administration (NASA) sent its Mars rover “Perseverance” atop an Atlas V rocket to the red planet to collect rock samples, it took the rover nearly seven months to reach its destination. This was only one step in a complex process that will take at least a decade to bring home these samples from Mars. While this is an unusually long wait for a sample shipment, it gives scientists ample time to find the best approach to study these rare and precious rocks.

In preparation, an international collaboration of scientists has started investigating sedimentary rock samples found in Iceland, a country whose terrain shares some compositional similarities and whose climate may be similar to ancient climates in certain Martian regions. Their results, published today in American Mineralogist, shed light on how high-resolution analyses of these complex, natural minerals can give scientists a deeper understanding of their geological history, both at home on Earth and 194 million miles away on Mars, though this requires careful interpretation. This collaboration is made up of researchers from the University of Maryland, NASA Goddard, Johnson Space Center, University of Göttingen, Chungbuk National University, and the National Synchrotron Light Source II (NSLS-II), a U.S. Department of Energy (DOE) Office of Science user facility at DOE’s Brookhaven National Laboratory.

McGill-led team maps ‘weather’ on a nearby brown dwarf in unprecedented detail

Study reveals patchy clouds and shifting atmospheric layers on a free-floating planetary-mass object just 20 light-years away, offering potential insights into planet and star formation
Image Credit: Anastasiia Nahurna.

Researchers at McGill University and collaborating institutions have mapped the atmospheric features of a planetary-mass brown dwarf, a type of space object that is neither a star nor a planet, existing in a category in-between. This particular brown dwarf’s mass, however, is just at the threshold between being a Jupiter-like planet and a brown dwarf. It has thus also been called a free-floating, or rogue, planet, not bound to a star. Using the James Webb Space Telescope (JWST), the team captured subtle changes in light from SIMP 0136, revealing complex, evolving weather patterns across its surface.

“Despite the fact that right now we cannot directly image habitable planets around other stars, we can develop methods of learning about the meteorology and atmospheric composition on very similar worlds,” said Roman Akhmetshyn, a McGill MSc student in physics and the study's lead author.