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  • NASA Announces “Realignment” Toward Human Spaceflight Kimberly M. S. Cartier
    Research & Developments is a blog for brief updates that provide context for the flurry of news regarding law and policy changes that impact science and scientists today. Today, NASA announced an agencywide realignment that includes combining related mission directorates to sharpen the agency’s focus on human spaceflight. “This initiative reflects NASA’s extreme focus on executing the mission in direct support of the National Space Policy,” NASA Administrator Jared Isaacman said i
     

NASA Announces “Realignment” Toward Human Spaceflight

22 May 2026 at 17:37
A photo of the Orion spacecraft in front of a crescent of the farside of the Moon, which is in front of a crescent of the Earth in the distance

Research & Developments is a blog for brief updates that provide context for the flurry of news regarding law and policy changes that impact science and scientists today.

Today, NASA announced an agencywide realignment that includes combining related mission directorates to sharpen the agency’s focus on human spaceflight.

“This initiative reflects NASA’s extreme focus on executing the mission in direct support of the National Space Policy,” NASA Administrator Jared Isaacman said in a press release about the realignment.

The National Space Policy refers to Executive Order 14369: Ensuring American Space Superiority, which was released by the Trump administration in December 2025. The order sets national priorities of returning Americans to the Moon, establishing a lunar base, developing a nuclear reactor in space, developing the commercial space economy, and enhancing the United States’ national security space architecture.

A dark Moon haloed by eclipsed sunlight, with several stars dotted all around.
NASA’s Artemis II crew captured this image of the Moon eclipsing the Sun during their flyby of the Moon on 6 April 2026. Credit: NASA

NASA’s six existing mission directorates will be slimmed down to four. Exploration Systems Development and Space Operations will be combined into a new Human Spaceflight Mission Directorate and will facilitate human spaceflight in low-Earth and lunar space environments. Aeronautics Research and Space Technology will be folded into a new Research and Technology Mission Directorate, tasked with researching and developing nuclear power and propulsion. The structure of the Science Mission Directorate (SMD) and Mission Support Directorate remain unchanged at the time of publication. All directorate leaders will now report directly to the NASA Administrator (Isaacman) to ensure that each remains focused on their directorate’s new mission.

“There will be no reduction in force, no program cancellations, no closures, but we will achieve cost savings through more efficient execution and taking an active role in delivering the outcomes the world has been waiting for from NASA,” Isaacman said.

More Efficient?

At first glance, it is hard to see how combining four mission directorates into two, refocusing the missions of each, and pushing for increased efficiency and cost reduction will not result in some loss of talent either through positions being eliminated or individuals finding themselves in jobs they do not want to hold.

In a letter to NASA employees, Isaacman went into more detail about the specifics of this realignment and described how it will shift the agency’s internal bureaucratic authority away from directorates and toward NASA’s field centers. Prior to this, centers like Goddard Space Flight Center in Greenbelt, Md., and Johnson Space Center in Houston would need to compete for funding that had been appropriated to directorates based on the programs or missions they were tasked with.

A NASA source based in Houston told Ars Technica that the competition for funding “has been an absolute disaster.”

This new realignment “will adjust the funding distribution, so Centers have the financial support needed to sustain the baseline critical capabilities independent of near-term mission assignment,” Isaacman stated. “This shift will allow Center Directors to focus on maintaining the infrastructure, workforce, and capabilities required for current and future missions.”

Isaacman was unclear about when these changes will take effect, and policy analysts are unsure whether the realignment will be recognized by Congress through its appropriations process. The most recent Fiscal Year 2027 appropriations bill for NASA, which advanced out of the House Committee on Commerce, Justice, and Science on 13 May, allocates funding for six mission directorates, not four. The Senate appropriations committee is expected to release its proposed budget for NASA in the coming weeks, and the two bills must still undergo a lengthy reconciliation process.

In fiscal year 2026, Congress broke with the president’s budgetary priorities for NASA and passed a budget that ignored several of the administration’s proposed financial and mission cuts. Whether Congress will do the same this year and maintain the prior breakdown of directorates will become clear in the coming months.

—Kimberly M. S. Cartier (@astrokimcartier.bsky.social), Staff Writer

These updates are made possible through information from the scientific community. Do you have a story about how changes in law or policy are affecting scientists or research? Send us a tip at eos@agu.org.

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  • Undulations in Auroral Arcs at Plasmaspheric Plume Boundary Andrew Yau
    Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: AGU Advances Most auroras appear in the “auroral oval” at high latitudes surrounding the magnetic poles. However, some can appear as a detached auroral arc from the auroral oval, at lower latitudes in mid-afternoon and connected to the oval only at a tip or two. Such a detached arc is believed to be linked to the “plasmaspheric plume,” the tongue-shaped extension of the plasmasphere during the recovery ph
     

Undulations in Auroral Arcs at Plasmaspheric Plume Boundary

21 May 2026 at 13:26
Photo of aurora taken from the International Space Station.
Editors’ Highlights are summaries of recent papers by AGU’s journal editors.
Source: AGU Advances

Most auroras appear in the “auroral oval” at high latitudes surrounding the magnetic poles. However, some can appear as a detached auroral arc from the auroral oval, at lower latitudes in mid-afternoon and connected to the oval only at a tip or two. Such a detached arc is believed to be linked to the “plasmaspheric plume,” the tongue-shaped extension of the plasmasphere during the recovery phase of a geomagnetic storm. (The plasmasphere is the torus-shaped region of cold, dense plasma above the low- and mid-latitude ionosphere.) The surface waves at the plume boundary cause it to ripple and modulate the various plasma waves in the plume.

Based on observations from multiple satellites and ground stations, Feng et al. [2026] find sawtooth-like undulations along the equatorward boundary of a detached auroral arc in the ultraviolet that was produced by energetic (>keV) electrons and accompanied by energetic (>10 keV) ions. The authors attribute the undulations to Electromagnetic Ion Cyclotron (EMIC) waves that are modulated by the surface waves and resonating with the energetic ions. The study unravels the fine-scale structures of detached auroral arcs and sheds important light on the dynamics underlying their formation.

Schematic illustration of the formation mechanism for the sawtooth-like undulations of a detached auroral arc. The surface waves modulate the Electromagnetic Ion Cyclotron (EMIC) waves in the plasmaspheric plume, causing the energetic ions to precipitate into the ionosphere and resulting in the formation of an afternoon detached auroral arc with sawtooth-like undulations. Credit: Feng et al. [2026], Figure 4

Citation: Feng, H., Wang, D., Hao, Y., Miyoshi, Y., Fu, H., Jun, C.-W., et al. (2026). First observation of sawtooth-like undulations in afternoon detached auroral arcs modulated by surface waves at the plasmaspheric plume boundary. AGU Advances, 7, e2025AV002234. https://doi.org/10.1029/2025AV002234

—Andrew Yau, Editor, AGU Advances

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  • Astronomers Find 10,000 Potential New Exoplanets Kimberly M. S. Cartier
    Research & Developments is a blog for brief updates that provide context for the flurry of news that impacts science and scientists today. To date, astronomers have confirmed the existence of just under 6,300 exoplanets. New research could more than double that number, adding a potential 10,000 new planets in one fell swoop. Yes, that’s right. A 1 with 4 zeros. The T16 project has announced the discovery of 10,091 exoplanet candidates observed by NASA’s Transiting Exoplanet Sur
     

Astronomers Find 10,000 Potential New Exoplanets

13 May 2026 at 14:45
An artist’s illustration of an array of exoplanets with a 9 by 12 grid of colorful planets in a gibbous phase. A second grid of shadowed planets sits behind it.

Research & Developments is a blog for brief updates that provide context for the flurry of news that impacts science and scientists today.

To date, astronomers have confirmed the existence of just under 6,300 exoplanets. New research could more than double that number, adding a potential 10,000 new planets in one fell swoop.

Yes, that’s right. A 1 with 4 zeros.

The T16 project has announced the discovery of 10,091 exoplanet candidates observed by NASA’s Transiting Exoplanet Survey Satellite (TESS). Since 2018, the all-sky survey has been monitoring more than 200,000 nearby stars using the transit method, which detects the faint dip in a star’s light when a planet crosses in front of it. Astronomers typically require 3 dips to be sure that what they’re seeing is actually a planet and not a one-off event such as an asteroid or comet in that distant star system.

The T16 project analyzed the light curves of more than 54 million stars observed during the first year of the TESS mission. The project’s analysis technique allowed it to search for planets around stars up to 16 times fainter than TESS typically searches, drastically increasing the field of discovery.

That’s more than were detected in the entirety of NASA’s Kepler mission and its follow-on K2.

Their pipeline detected 11,554 planet candidates. Of those, 1,052 of those had been detected previously and 411 only had one transit—not enough to confirm a planet.

That leaves 10,091 potential new planets. That’s more than were detected in the entirety of NASA’s Kepler mission and its follow-on K2 and more than double the existing planet candidates from TESS that await confirmation. These discoveries will be published in the Astrophysical Journal Supplement.

All of the new planet candidates orbit their stars quickly, with orbital periods between 12 hours and 27 days. Although most of the stars that TESS observes are smaller and cooler than the Sun, those close orbits likely mean that most of those planets are far too hot to be habitable.

 
Learn More

•  Read the paper: The T16 Planet Hunt
•  More context from The Bad Astronomer
 

The T16 project team confirmed the planet-hood of one of their candidates not using the transit method, but a different method that measures the gravitational tug a planet exerts on its host star. That planet, TIC 183374187, is hot and slightly larger than Jupiter.

The remaining 10,090 newly discovered planet candidates require additional verification to determine whether they truly are planets or not. But given the rigor of the team’s analysis and the requirement of at least 3 transits to even make this list, it’s likely that most of the new discoveries are indeed planets.

“Astronomers are a bit conservative when it comes to claims like this, and want to be sure they pass a bunch of tests to make sure everything was done correctly and these planets actually exist,” astronomer Phil Plait wrote in his Bad Astronomy Newsletter. “Having said that, the process the astronomers went through looks legit to me, and I would bet the majority of these new candidates are real. That’s amazing.”

—Kimberly M. S. Cartier (@astrokimcartier.bsky.social), Staff Writer

These updates are made possible through information from the scientific community. Do you have a story about science or scientists? Send us a tip at eos@agu.org.

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  • Interstellar Comet Was Born in a Very Cold Place Kimberly M. S. Cartier
    In late 2025, astronomers spotted an interstellar comet making a quick trip through the solar system. 3I/ATLAS was discovered in July when it was just inside Jupiter’s orbit. It’s now about halfway between Jupiter and Saturn and getting farther away every day. The European Space Agency’s Jupiter Icy Moons Explorer (ESA JUICE) mission, on its way to Jupiter, imaged 3I/ATLAS on 5 November 2025 when the comet was 64 million kilometers from the spacecraft. Credit: ESA/Juice/JANUS, CC BY-SA 3.0 I
     

Interstellar Comet Was Born in a Very Cold Place

7 May 2026 at 13:11
A bright white point is surrounded by a large, soft blue glow that fades gradually into a dark background. Thin, faint streaks appear diagonally across the image, suggesting motion or stars in the distance. The overall effect is of a luminous object in space, radiating light against a deep, dark backdrop.

In late 2025, astronomers spotted an interstellar comet making a quick trip through the solar system. 3I/ATLAS was discovered in July when it was just inside Jupiter’s orbit. It’s now about halfway between Jupiter and Saturn and getting farther away every day.

A bright, oval shape glows near the center of a black, star-filled sky as it moves diagonally toward the top right of the frame. It has a soft halo around it and a faint, wispy tail stretching downward. Countless tiny white stars dot the background.
The European Space Agency’s Jupiter Icy Moons Explorer (ESA JUICE) mission, on its way to Jupiter, imaged 3I/ATLAS on 5 November 2025 when the comet was 64 million kilometers from the spacecraft. Credit: ESA/Juice/JANUS, CC BY-SA 3.0 IGO

Astronomers have been observing 3I/ATLAS throughout its journey inward toward the Sun and back out again, compiling the most comprehensive and detailed view thus far of an interstellar object, including the chemistry of the gases that sublimated from its surface and formed its coma and tail.

In a first-of-its-kind observation of an interstellar object (ISO), researchers have discovered that the ratio of deuterium to hydrogen in 3I/ATLAS’s outgassed water is 30–40 times higher than in solar system objects. That suggests that the comet formed in a much colder environment than our own solar system did.

“It is always hard to really pinpoint where these objects form,” said Luis E. Salazar Manzano, the lead researcher on these observations and a doctoral student at the University of Michigan in Ann Arbor. “We know that they were formed in different parts of the galaxy, but it’s hard to connect what we measure with how they were formed. These types of measurements, such as the relative abundance of deuterium to hydrogen in water, are one of the best ways we have to actually [learn] about their forming conditions and their evolution.”

Coming In from the Cold

Water appears to be ubiquitous throughout the universe, sprinkled within distant galaxies and in star-forming nebulae. But there are different flavors of water: heavy, semiheavy, and plain old H2O. In the molecular clouds where stars form, the cold environment favors a chemical reaction that increases the amount of gaseous deuterium (D), an isotope of hydrogen, relative to regular hydrogen atoms. That deuterium then bonds with hydrogen and oxygen atoms to create semiheavy water, or HDO.

By measuring the quantity of semiheavy water relative to regular water in an object, scientists can infer the object’s ratio of deuterium to hydrogen, or D/H, and decode the physical conditions in which that water formed. Astronomers have made such measurements for baby stars, planet-forming disks, solar system comets, and meteorites, as well as Earth’s ocean.

“What is fundamentally important about ISOs is that they are physical leftovers of the process of forming another planetary system and they can give us clues to that process,” said Karen Meech, an astrobiologist at the University of Hawaiʻi at Mānoa who was not involved with this research.

“The conditions in the stellar system in which 3I/ATLAS formed may have been quite different from the one in the solar system.”

The team observed 3I/ATLAS with the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile on November 2025 when the comet was 335 million kilometers (208 million miles) from Earth. It had just passed its closest approach to the Sun and was as bright as it was ever going to be. This timing was critical for the measurements the team wanted to make because the signal for HDO is very subtle, especially when it has to compete with the much more abundant H2O in the comet and within Earth’s atmosphere, Salazar Manzano explained.

Those measurements showed that for every 1,000 hydrogen atoms in 3I/ATLAS, there were about 5–7 deuterium atoms. While that’s not a lot, the ratio is still at least 40 times more than what’s found in ocean water and at least 30 times the average value in solar system comets.

“The conditions in the stellar system in which 3I/ATLAS formed may have been quite different from the one in the solar system,” said Paul Hartogh, a physicist and atmospheric science researcher at the Max Planck Institute for Solar System Research in Göttingen, Germany.

The first interstellar object, 1I/ʻOumuamua, did not outgas any material, and although the second object, 2I/Borisov, did, it was not bright enough to detect deuterium. 3I/ATLAS was the first opportunity astronomers had to measure the D/H ratio of an interstellar comet. Those measurements suggest that 3I/ATLAS formed in a much colder galactic environment than the solar system did, less than 30°C above absolute zero. The team published these results in Nature Astronomy in April.

Planning for the Next Interstellar Visitor

Hartogh, who was not involved with this research, said that on the one hand, 3I/ATLAS’s high deuterium enrichment is surprising because it is higher than that of any known comet. On the other hand, he added, some scientists predicted such high values for cometary water several decades ago.

Meech said she found these results “really interesting.” She never expected all other solar systems to have formed just like ours, and 3I/ATLAS fits with that idea.

“This gives us an intriguing look into the processes of planetary system formation—and that there are differences from our own solar system,” Meech said. “It is too early to tell what this implies for the formation of planets or habitable worlds. We are just at the beginning of an exciting story.”

“The fact that we were able to make this measurement with 3I will allow us to better prepare what to expect with the next generation of interstellar objects.”

3I/ATLAS is getting harder to see with telescopes, but astronomers still have a lot of data from when it was much brighter to go through, Salazar Manzano said. Teams around the world are working on creating a holistic picture of the comet’s chemistry and evolution.

What’s more, “the fact that we were able to make this measurement with 3I will allow us to better prepare what to expect with the next generation of interstellar objects,” Salazar Manzano said.

Scientists expect that the Vera C. Rubin Observatory could discover between 6 and 51 interstellar objects within the next 10 years. If objects are detected early enough in their journey through the solar system, “there may be enough time to coordinate observations with ground-based and spaceborne telescopes, taking advantage of the recent experience gained by the multiple 3I/ATLAS observations,” Hartogh said.

“These are rare opportunities to study another planetary nursery up close, and we have to take advantage of each new ISO to learn as much as we can,” Meech said. “It may be harder for a large number of individual teams to get all the data they want, so I think coordination and collaboration is needed more than ever.”

—Kimberly M. S. Cartier (@astrokimcartier.bsky.social), Staff Writer

Citation: Cartier, K. M. S. (2026), Interstellar comet was born in a very cold place, Eos, 107, https://doi.org/10.1029/2026EO260141. Published on 7 May 2026.
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  • 通往真正可持续太空供水系统的路径 Faith Ishii
    Source: Water Resources Research This is an authorized translation of an Eos article. 本文是Eos文章的授权翻译。 如果人类想要在太空生活,无论是在航天器里还是在火星上,首先要解决的一个问题就是如何获取水,来满足饮用、卫生需求以及为维持生命所需的植物提供水分。即便只是将水运送到近地轨道上的国际空间站(ISS),也需要花费数万美元。因此,找到在太空中高效、持久且可靠地获取和再利用水资源的方法,对于长期在太空居住至关重要。 目前的系统,比如国际空间站上的环境控制与生命支持系统(ECLSS),为闭合式水回收提供了蓝图,但它们还需要改进才能适应未来的应用。与此同时,近期的技术和科学进步正为在严苛环境下寻找、净化和管理水资源开辟新的途径。在一篇新的综述中,Olawade等人概述了地外水资源管理的现状,以及该领域的前景和挑战。 作者指出,太空水系统需要具备闭环、高效和持久耐用的特性,同时还要满足低能耗的要求。目前,ECLSS能耗过高,其效率可能也不足以满足长期任务的需求。未来建议采用的过
     

通往真正可持续太空供水系统的路径

21 April 2026 at 12:39
国际空间站上的宇航员Kayla Barron将一个银色的金属圆筒(大小和汽水罐差不多)举到镜头前。
Source: Water Resources Research

This is an authorized translation of an Eos article. 本文是Eos文章的授权翻译。

如果人类想要在太空生活,无论是在航天器里还是在火星上,首先要解决的一个问题就是如何获取水,来满足饮用、卫生需求以及为维持生命所需的植物提供水分。即便只是将水运送到近地轨道上的国际空间站(ISS),也需要花费数万美元。因此,找到在太空中高效、持久且可靠地获取和再利用水资源的方法,对于长期在太空居住至关重要。

目前的系统,比如国际空间站上的环境控制与生命支持系统(ECLSS),为闭合式水回收提供了蓝图,但它们还需要改进才能适应未来的应用。与此同时,近期的技术和科学进步正为在严苛环境下寻找、净化和管理水资源开辟新的途径。在一篇新的综述中,Olawade等人概述了地外水资源管理的现状,以及该领域的前景和挑战。

作者指出,太空水系统需要具备闭环、高效和持久耐用的特性,同时还要满足低能耗的要求。目前,ECLSS能耗过高,其效率可能也不足以满足长期任务的需求。未来建议采用的过滤和回收方法包括:利用光催化技术通过光线净化水,利用生物反应器过滤尿液和废水,利用离子交换系统去除提取水中的溶解盐和重金属,以及利用紫外线臭氧消毒杀灭病原体。每种方法各有优缺点:例如,生物反应器中的微生物燃料电池可以发电,而光催化净化则能耗较低。

在月球或火星这样的地方获取水,要么需要从风化层中提取水,要么需要钻探冰体。如何为水回收系统提供足够的能源也是一个问题,因此开发节能系统是需要优先考虑的事项。水系统的耐久性也很重要,既要保护宇航员的安全,又要能减少繁重的维护工作。

新兴技术有望应对其中许多挑战。作者们指出两个具有巨大应用前景的领域,一是纳米技术的发展,它可用于制造定制化程度更高、过滤效果更佳且耐污染的膜材料,二是人工智能(AI)技术在水系统自主管理中的应用。(Water Resources Research, https://doi.org/10.1029/2025WR041273, 2026)

—科学撰稿人Nathaniel Scharping (@nathanielscharp)

This translation was made by Wiley. 本文翻译由Wiley提供。

Read this article on WeChat. 在微信上阅读本文。

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  • Taking the Pulse of Atmospheric Drag to Predict Satellite Trajectory Alberto Montanari
    Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: AGU Advances In low Earth orbit (typically below about 700 kilometers altitude), atmospheric drag is the primary source of uncertainty when predicting the trajectories of satellites. These prediction errors largely arise from limitations and inaccuracies in the models used to estimate the density of the upper atmosphere, particularly within the thermosphere. Mutschler et al. [2026] introduce a new met
     

Taking the Pulse of Atmospheric Drag to Predict Satellite Trajectory

6 May 2026 at 12:00
Illustration of a satellite orbiting Earth.
Editors’ Highlights are summaries of recent papers by AGU’s journal editors.
Source: AGU Advances

In low Earth orbit (typically below about 700 kilometers altitude), atmospheric drag is the primary source of uncertainty when predicting the trajectories of satellites. These prediction errors largely arise from limitations and inaccuracies in the models used to estimate the density of the upper atmosphere, particularly within the thermosphere.

Mutschler et al. [2026] introduce a new method for estimating atmospheric density along the path of an individual satellite by using Energy Dissipation Rates (EDRs). The derived single-satellite density measurements provide valuable insight into variations in thermospheric density and can help characterize how the upper atmosphere responds to disturbances such as geomagnetic storms. Incorporating these observations can contribute to ultimately improving the accuracy of satellite orbit predictions.

Effective density and Space Force effective density estimated by the Kosmos 1508 satellite (plotted on the right-hand y axes) compared to estimates from satellites Swarm-A and Swarm-C (plotted on the left-hand y-axes). Credit: Mutschler et al. [2026], Figure 17a

Citation: Mutschler, S., Pilinski, M., Zesta, E., Oliveira, D. M., Delano, K., Garcia-Sage, K., & Tobiska, W. K. (2026). First results of a new inversion tool for thermospheric neutral mass density computations during severe geomagnetic storms. AGU Advances, 7, e2025AV002079. https://doi.org/10.1029/2025AV002079

—Alberto Montanari, Editor-in-Chief, AGU Advances

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  • What Winds Whip Up Otherworldly Waves? Kimberly M. S. Cartier
    Wind-driven waves on Earth move sediments and shape shorelines. They transport energy between the atmosphere and planetary surface and also mix bodies of liquid, affecting both chemistry and biology. On other worlds with surface liquids, either now or in the past, wind waves would likely perform the same function and so would play a key role in climate and astrobiological potential. “They’re basically the interface between how the atmosphere communicates with the landscape, especially at the
     

What Winds Whip Up Otherworldly Waves?

21 May 2026 at 13:29
Orange and blue tinted waves with sunlight glinting off the surface.

Wind-driven waves on Earth move sediments and shape shorelines. They transport energy between the atmosphere and planetary surface and also mix bodies of liquid, affecting both chemistry and biology. On other worlds with surface liquids, either now or in the past, wind waves would likely perform the same function and so would play a key role in climate and astrobiological potential.

“They’re basically the interface between how the atmosphere communicates with the landscape, especially at the coast.”

New research went back to the fundamentals and explored the conditions that can generate waves on worlds with different physical properties and different liquids, such as Titan, Mars, and select exoplanets.

“Wind waves are really interesting phenomena,” said Una Schneck, a planetary science doctoral student at the Massachusetts Institute of Technology (MIT) in Cambridge. “They’re basically the interface between how the atmosphere communicates with the landscape, especially at the coast.”

The Physics of Waves

Past models of wind generation on other planets struggled because they tended to start from preexisting models of Earth waves. Those models were developed to describe waves in Earth’s specific combination of gravity, atmosphere, and surface liquid, namely, water, said Schneck, who led the new research. Such models were sometimes tailored to describe a particular location and season. Adapting those models for conditions on other worlds, including other liquids like methane and sulfuric acid, always seems to leave traces of Earth behind.

However, the physics of what creates wind-driven waves should be universal, Schneck said, so the team went back to the basics of wave generation. They developed a wave model that explores the relationship between a world’s bulk properties, like gravity and air density, and liquid properties, like surface tension, to determine the wind strength needed to produce a wave.

The team “created this model that went back to the basic physics of waves, instead of just trying to fit to known wave conditions,” said Taylor Perron, an MIT geomorphologist and planetary scientist and coauthor of the research.

Side-by-side images of areas with past or current lakes. On the left is an aerial image of Gale Crater on Mars, with orange dusty plains surrounding a shadowed depression with a mountain in the middle. On the right is a composite image of Titan’s northern hemisphere. The ground is colored gold, and the lakes are in deep blues.
The Curiosity rover landed in Gale Crater on Mars (left) and has since found evidence—wavy bedforms—that this former crater lake had waves. Titan’s northern hemisphere hosts a sprawling lake district (right). The shores of one of the moon’s largest bodies of liquid, Ligeia Mare, shows evidence of wave activity. Credit: Left: NASA/JPL-Caltech/ESA/DLR/FU Berlin/MSSS; right: NASA/JPL-Caltech/ASI/USGS

The model showed that the threshold wind speed to generate a wave is lower for liquids with less surface tension, which makes it easier to change the liquid’s shape. Higher air density provides more force to push against a liquid’s surface, and lower gravity makes it easier for a wave to rise up—both factors allow a weaker wind to create a wave. The team published these results in the Journal of Geophysical Research: Planets in April.

Waves on Other Worlds

The team first tested their model on the only set of wind and wave data we have—Earth. They used 20 years of wave and weather data for Lake Superior. The model found, correctly, that it takes wind speeds of 2.2 meters per second to generate waves on the lake’s surface and accurately predicted the height of waves for different wind speeds.

They then used the model to predict wave conditions on other worlds. They started with Mars, which likely had ancient oceans and lakes. Winds of 1.2 meters per second would have created waves in the lake that filled Gale Crater millions of years ago. A wave in Gale Crater would have been taller than a wave on Earth produced by wind of the same strength owing to Mars’s lower gravity.

The story is similar on Titan, the largest moon of Saturn. Waves in Titan’s hydrocarbon lakes would swell with a mere 0.5 meter per second of wind and would rise higher than an Earth wave under similar wind conditions. But they would travel much more slowly than Earth waves and would be spaced farther apart.

“The paper represents our best theoretical understanding of how we expect for waves to behave in a variety of environments,” said Jason Barnes, a planetary scientist at the University of Idaho in Moscow who was not involved with this research. “The movie of Titan waves is particularly awesome—very slow moving for such large amplitudes! Although I don’t expect waves to get that high ever in Titan’s sluggish atmosphere, it’s fun to be able to visualize what they might look like if they did.”

“In theory, this is something that people could do.”

The team also explored wave-generating conditions on three Earth-sized exoplanets. The possible sulfuric acid lakes of the exo-Venus Kepler-1649 b would grow in winds of 5.3 meters per second but would grow to a height similar to that of Earth waves because of its Earth-like gravity. Water lakes on LHS 1140 b would grow in 2.7 meter winds, similar to those on Earth, but would not grow as high because of its higher gravity. And on 55 Cancri e, a lava world, it would take winds of 37 meters per second—a category 1 hurricane—to move tiny waves of molten rock.

“Would you be able to ever detect this? Is this a useful thing to think about, or is it just a fun thought experiment?” Schneck asked. “If the waves are tall enough, you should be able to detect a change in the polarization [of an exoplanet’s light curve] that would not only suggest that there is a liquid surface on that exoplanet, but that liquid surface has waves.…In theory, this is something that people could do.”

Will We See It? Not Soon

Right now, the only world known to have surface liquid other than Earth is Titan, but we don’t have the right observations of Titan to test the new model. The European Space Agency’s Huygens probe landed on the moon in 2005, but nowhere near the northern lake district. NASA’s Cassini mission (of which Huygens was a part) did not detect any waves but did observe a changing lake shore that hinted at wave activity.

It’s possible that Titan’s waves are seasonal and Cassini just didn’t have the right timing, Perron noted. Temperature changes during Saturn’s year could affect wind speeds and also the composition of Titan’s lakes, changing the conditions of wave generation.

Still, the wind speed needed to make a wave on Titan is so low that “it would be very surprising if waves never formed. It just may be difficult to catch them when they’re there,” he said.

“The best way to test this work would be to send a sea probe to float or motor on one of Titan’s big 3 seas.”

“The best way to test this work would be to send a sea probe to float or motor on one of Titan’s big 3 seas—Kraken Mare, Ligeia Mare, or Punga Mare,” Barnes said. “Such a ‘buoy’ probe would be able to simultaneously measure both the sea conditions and the wind conditions, allowing for a comprehensive test of the model.”

Alas, no such mission is in the works, and the upcoming Dragonfly mission won’t travel near any lakes to test this theory either. A future Titan orbiter might provide that information, while a current or future Mars rover might yet gather evidence showing how lakes worked in that planet’s past.

“The improved understanding of waves from this paper might help to constrain the possibilities for wave erosion at the margins of bodies of water…thereby helping us to probe into the past climates of Mars and Titan,” Barnes said.

—Kimberly M. S. Cartier (@astrokimcartier.bsky.social), Staff Writer

Citation: Cartier, K. M. S. (2026), What winds whip up otherworldly waves?, Eos, 107, https://doi.org/10.1029/2026EO260165. Published on 21 May 2026.
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  • ✇Eos
  • Rocket Launches and Reentries Harm Earth’s Ozone Layer Sarah Stanley
    Source: Earth’s Future The space industry is surging. In coming years, nearly 10,000 spacecraft are slated to launch into low-Earth orbit for a variety of purposes, such as global surveillance, space tourism, and satellite “megaconstellations” providing internet service. Rocket engine exhaust, as well as the burnup of inactive satellites and rocket parts reentering Earth’s atmosphere, releases a suite of pollutants. These chemicals have long been considered to pose little threat to our cl
     

Rocket Launches and Reentries Harm Earth’s Ozone Layer

8 June 2026 at 13:23
This image shows a rocket launching into a blue sky from its launchpad. A bright white and orange tail is emitted from the bottom of the rocket, transitioning into cloudlike billows of gas closer to the ground. A body of still water is in the midground, and grasses and shrubs are in the foreground.
Source: Earth’s Future

The space industry is surging. In coming years, nearly 10,000 spacecraft are slated to launch into low-Earth orbit for a variety of purposes, such as global surveillance, space tourism, and satellite “megaconstellations” providing internet service.

Rocket engine exhaust, as well as the burnup of inactive satellites and rocket parts reentering Earth’s atmosphere, releases a suite of pollutants. These chemicals have long been considered to pose little threat to our climate, given the historically small size of the space industry. Now, the sector’s rapid growth will send its emissions skyrocketing—but scientists don’t yet have a clear picture of the environmental ramifications.

An analysis by Vliex et al. of rockets launched in 2022 revealed that spaceflight depletes the ozone layer and contributes to global warming, with a significant portion of this ozone loss attributable to nitrogen oxide emissions released by objects reentering Earth’s atmosphere.

The researchers calculated emissions from all 186 rockets launched in 2022, as well as all 472 objects—with a combined total mass of nearly 5,000 tons—that reentered the atmosphere that year. They conducted computational simulations of each launch’s trajectory and emissions at various altitudes up to 100 kilometers, and they calculated emissions released by object reentry. They also accounted for the effects of chemical reactions that occur in rocket exhaust plumes, which alter emissions’ chemical composition.

Incorporation of the calculated emissions into GEOS-Chem, a computational model of atmospheric chemistry, revealed their ozone-depleting and Earth-warming effects, with reentry emissions identified as playing a key role in ozone depletion. The researchers found that accounting for plume reactions reduced the estimated effects of spaceflight emissions, highlighting the value of considering plume chemistry in future assessments.

The analysis also underscored the varying effects of different rocket fuel types. Solid-state fuels, used recently in rocket boosters for NASA’s Artemis II mission to return astronauts to the Moon, appeared to cause the greatest amount of ozone depletion relative to propellant mass, while rocket-grade kerosene caused the greatest amount of warming.

On the basis of their findings, the researchers call for further research into reentry emissions and rocket plume chemistry as the space industry continues to expand and evolve. (Earth’s Future, https://doi.org/10.1029/2025EF007795, 2026)

—Sarah Stanley, Science Writer

The logo for the United Nations Sustainable Development Goal 3 is at left. To its right is the following text: The research reported here supports Sustainable Development Goal 3. AGU is committed to supporting the United Nations 2030 Agenda for Sustainable Development, which provides a shared blueprint for peace and prosperity for people and the planet, now and into the future.
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Citation: Stanley, S. (2026), Rocket launches and reentries harm Earth’s ozone layer, Eos, 107, https://doi.org/10.1029/2026EO260183. Published on 8 June 2026.
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  • ✇Eos
  • Timing of Geomagnetic Storms Shapes Their Impact Alberto Montanari
    Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: AGU Advances Solar eruptions can trigger geomagnetic storms that disrupt satellites, GPS, and power grids, affecting daily activities and technology. Therefore, it is extremely important to understand these storms in order to mitigate their impact. Previous studies mainly focused on interplanetary conditions. Ghag et al. [2026] investigate the interaction between solar ultraviolet light (EUV) during st
     

Timing of Geomagnetic Storms Shapes Their Impact

15 April 2026 at 12:00
Illustration of the Sun and Earth's magnetosphere.
Editors’ Highlights are summaries of recent papers by AGU’s journal editors.
Source: AGU Advances

Solar eruptions can trigger geomagnetic storms that disrupt satellites, GPS, and power grids, affecting daily activities and technology. Therefore, it is extremely important to understand these storms in order to mitigate their impact. Previous studies mainly focused on interplanetary conditions.

Ghag et al. [2026] investigate the interaction between solar ultraviolet light (EUV) during storms and the Earth magnetic field, taking into account its misalignment and offset with respect to the Earth’s rotational axis, which depend on time. Such misalignment and offset induce variations in EUV exposure in turn influencing the ionosphere and its interaction with the magnetosphere.

The study applies the Multiscale Atmosphere-Geospace Environment (MAGE), a physics based fully coupled whole geospace model. The causal relationship between storm timing and storm effect is explored revealing insights on our capability to predict storm impact based on the time dependent Earth system state.

The rotation of the magnetic pole around the rotational pole in the NH and SH. The location of the rotational pole is denoted in blue and the magnetic pole in red. Credit: Ghag et al. [2026], Figure 6c

Citation: Ghag, K., Lotko, W., Pham, K., Lin, D., Merkin, V., Raghav, A., & Wiltberger, M. (2026). Universal time influence on stormtime magnetosphere ionosphere coupling. AGU Advances, 7, e2025AV002071. https://doi.org/10.1029/2025AV002071

—Alberto Montanari, Editor-in-Chief, AGU Advances

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  • ✇Eos
  • 超级闪电之外-隐形超级风暴揭示木星上的闪电 Saima May Sidik
    Source: AGU Advances This is an authorized translation of an Eos article. 本文是Eos文章的授权翻译。 木星的闪电一直是行星科学家关注的焦点,因为它标志着风暴活跃的区域,研究人员可以在这些区域深入研究以进一步了解木星大气中的对流现象。 远距离观测闪电并非易事,因此科学家们将研究重点放在最容易观测的闪电上:夜间发生的强闪电。因此,一些研究得出结论,木星上的闪电都与地球上最强的闪电——“超级闪电”——类似。然而,这一结论最近受到了质疑,因为NASA朱诺号探测器上的高灵敏度星体追踪相机探测到了微弱的浅层闪电。 Wong等人进行了更深入的研究,重点观察了2021年和2022年木星北赤道带的闪电高度集中在一些强大的孤立风暴中的情形,研究人员将这些风暴称为“隐形超级风暴”。这种不寻常的气象条件使研究人员能够更精确地确定闪电的位置。 科学家们并没有仅仅关注可见光,而是利用了朱诺号探测器携带的微波辐射计和Waves实验的数据。朱诺号在过去十年中一直在环绕木星运行。无线电波只是闪电产生的电磁辐射的一
     

超级闪电之外-隐形超级风暴揭示木星上的闪电

18 May 2026 at 12:52
木星带有条纹和漩涡状图案的表面覆盖着一条从上到下延伸的黄色线条,与一系列蓝色圆点相交。旁边的小图展示了木星的更近距离特写。
Source: AGU Advances

This is an authorized translation of an Eos article. 本文是Eos文章的授权翻译。

木星的闪电一直是行星科学家关注的焦点,因为它标志着风暴活跃的区域,研究人员可以在这些区域深入研究以进一步了解木星大气中的对流现象。

远距离观测闪电并非易事,因此科学家们将研究重点放在最容易观测的闪电上:夜间发生的强闪电。因此,一些研究得出结论,木星上的闪电都与地球上最强的闪电——“超级闪电”——类似。然而,这一结论最近受到了质疑,因为NASA朱诺号探测器上的高灵敏度星体追踪相机探测到了微弱的浅层闪电

Wong等人进行了更深入的研究,重点观察了2021年和2022年木星北赤道带的闪电高度集中在一些强大的孤立风暴中的情形,研究人员将这些风暴称为“隐形超级风暴”。这种不寻常的气象条件使研究人员能够更精确地确定闪电的位置。

科学家们并没有仅仅关注可见光,而是利用了朱诺号探测器携带的微波辐射计Waves实验的数据。朱诺号在过去十年中一直在环绕木星运行。无线电波只是闪电产生的电磁辐射的一种形式,但它却是一种特别有价值的信息来源,因为即使云层或其他大气成分阻挡了视觉信号,科学家们仍然可以对其进行研究。这种方法使研究人员能够超越其他研究人员以往关注的那些强烈的夜间闪电,去探索其他类型的闪电。

研究人员报告称,在这些隐形超级风暴中,闪电无线电脉冲的出现频率为每秒三次,这与之前一些夜侧成像研究中的闪电频率相似。然而,这些闪电的强度仍然存在争议。一些闪电的强度可能与地球大气层中发现的平均闪电强度相似。但由于所分析的木星闪电信号和地球闪电信号的无线电频率存在巨大差异,有些闪电的强度也可能是地球闪电的上百万倍。

—科学撰稿人Saima May Sidik (@saimamay.bsky.social)

This translation was made by Wiley. 本文翻译由Wiley提供。

Read this article on WeChat. 在微信上阅读本文。

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  • ✇Eos
  • Martian Aerosols Reveal Dynamics of Dust and Cloud Transport Arianna Piccialli and Beatriz Sánchez-Cano
    Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: Journal of Geophysical Research: Planets Dust and water ice clouds are ubiquitous on Mars; they regulate the planet’s climate and can affect measurements of other atmospheric components. Constraining their spatial and temporal variability is also essential for improving Martian general circulation models. Fedorova et al. [2026] use solar occultation measurements from the SPICAM infrared spectrometer on
     

Martian Aerosols Reveal Dynamics of Dust and Cloud Transport

Illustration of a satellite over the surface of Mars.
Editors’ Highlights are summaries of recent papers by AGU’s journal editors.
Source: Journal of Geophysical Research: Planets

Dust and water ice clouds are ubiquitous on Mars; they regulate the planet’s climate and can affect measurements of other atmospheric components. Constraining their spatial and temporal variability is also essential for improving Martian general circulation models.

Fedorova et al. [2026] use solar occultation measurements from the SPICAM infrared spectrometer on board the Mars Express orbiter to characterize nine Martian years (MY 28 through 36) of dust and water ice clouds. Because the spectrometer could not distinguish between these particles’ types, the researchers employ a new method integrating Mars Climate Sounder data and general climate model predictions to identify them.

The analysis reveals that the particles can reach altitudes up to 80 kilometers during perihelion, while their size remains relatively uniform with height. This suggests that Martian dust distribution is driven more by atmospheric dynamics and horizontal transport, capable of lifting and moving particles over vast distances, rather than by turbulent mixing against gravity alone.

The study also provides a detailed seasonal and spatial climatology of major Martian atmospheric features, including the Polar Hood Clouds, the Aphelion Cloud belt, and the Mesospheric Clouds. The detection of high-altitude clouds (70–90 km) during dust events confirms enhanced transport of water vapor into the upper atmosphere during both global and regional storms. These findings are consistent with simultaneous observations from the Atmospheric Chemistry Suite on the Trace Gas Orbiter.

These observations show that large-scale atmospheric dynamics, rather than local mixing alone, control how aerosols are distributed vertically on Mars, with important implications for the transport of water to the upper atmosphere and the planet’s climate evolution.

The figure shows how the water ice cloud layers vary with latitude and season (Ls), based on SPICAM observations. (a) altitude of the cloud layer in kilometers; (b) thickness of the cloud (optical depth); (c) average size of the ice particles in micrometers; and (d) number of particles within the layer (number density. The background color is the amount of dust in the atmosphere from Montabone et al. [2015]: red areas indicate high dust levels, while dark blue areas indicate low dust. Black open circles mark locations where no clear water ice clouds were detected. Credit: Fedorova et al. [2026], Figure 12

Citation: Fedorova, A. A., Luginin, M., Montmessin, F., Korablev, O. I., Bertaux, J.-L., Stcherbinine, A., & Lefèvre, F. (2026). Multiyear monitoring of aerosol vertical distribution on Mars by SPICAM IR/MEX. Journal of Geophysical Research: Planets, 131, e2025JE009388. https://doi.org/10.1029/2025JE009388  

—Arianna Piccialli, Associate Editor, and Beatriz Sanchez-Cano, Editor, JGR: Planets

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  • ✇Eos
  • What Makes Mars’s Magnetotail Flap? Sarah Stanley
    Source: AGU Advances The Sun continuously blasts charged, magnetic field–carrying particles, or plasma, in all directions. This solar wind interacts with the magnetic fields and atmospheres of several of our solar system’s planets and other bodies, sculpting long magnetic tails of charged particles—magnetotails—that stretch into space behind them. Magnetotails contain thin layers of electric current–carrying plasma sheets, which sometimes “flap” in an up-and-down waving motion. Spacecraft
     

What Makes Mars’s Magnetotail Flap?

20 April 2026 at 13:08
A large, round, glowing yellow shape is shown at right (the Sun), and a smaller, reddish-brown sphere is at left (Mars). Pale yellow streaks and thicker curving white lines radiate from the Sun in all directions. Mars appears to disrupt the flow of the pale yellow streaks, which deflect around it like water flowing around a pebble in a stream.
Source: AGU Advances

The Sun continuously blasts charged, magnetic field–carrying particles, or plasma, in all directions. This solar wind interacts with the magnetic fields and atmospheres of several of our solar system’s planets and other bodies, sculpting long magnetic tails of charged particles—magnetotails—that stretch into space behind them.

Magnetotails contain thin layers of electric current–carrying plasma sheets, which sometimes “flap” in an up-and-down waving motion. Spacecraft observations have revealed that flapping in Earth’s magnetotail can be driven by a process called magnetic reconnection, in which magnetic field lines rapidly break and then snap together in a new configuration, releasing stored energy. However, whether reconnection plays this same role beyond Earth has thus far been a mystery.

Wen et al. report the first evidence that magnetic reconnection may also trigger magnetotail flapping at Mars.

Unlike Earth, Mars lost its global magnetic field billions of years ago. But it still sports a magnetotail, thanks in large part to interactions between the solar wind and charged particles in its upper atmosphere. Strong magnetic fields embedded in certain patches of the Martian crust—remnants of its lost planet-wide field—also influence the magnetotail.

Until recently, Mars’s magnetotail could only be studied using observations from NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft. MAVEN showed that the Martian magnetotail is highly dynamic, with a structure that twists, shifts, and flaps—and from which charged particles may escape into space. But because MAVEN can observe only one part of the magnetotail at a time, it couldn’t identify what processes might trigger flapping.

Another spacecraft, China’s Tianwen-1 orbiter, has now provided a second set of eyes. The researchers analyzed simultaneous observations from the two spacecraft, finding that signatures of magnetic reconnection detected by MAVEN in the upstream part of the magnetotail tended to coincide with flapping events detected downstream by Tianwen-1.

Before or during flapping, the spacecraft also detected temporary, twisted plasma structures known as flux ropes. A similar link has previously been observed on Earth, and it suggests that flux ropes generated by magnetic reconnection upstream might propagate downstream, driving instabilities in the magnetotail’s plasma sheets and triggering flapping.

Though more research is needed to confirm these findings, they shed new light on how energy moves and is released in space around Mars—and possibly other planets and celestial objects. (AGU Advances, https://doi.org/10.1029/2026AV002343, 2026)

—Sarah Stanley, Science Writer

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Citation: Stanley, S. (2026), What makes Mars’s magnetotail flap?, Eos, 107, https://doi.org/10.1029/2026EO260123. Published on 20 April 2026.
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