Reading view

Rocket Launches and Reentries Harm Earth’s Ozone Layer

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.
A photo of a telescope array appears in a circle over a field of blue along with the Eos logo and the following text: Support Eos’s mission to broadly share science news and research. Below the text is a darker blue button that reads “donate today.”
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.
Text © 2026. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.
  •  

What Makes Mars’s Magnetotail Flap?

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

A photo of a telescope array appears in a circle over a field of blue along with the Eos logo and the following text: Support Eos’s mission to broadly share science news and research. Below the text is a darker blue button that reads “donate today.”
Citation: Stanley, S. (2026), What makes Mars’s magnetotail flap?, Eos, 107, https://doi.org/10.1029/2026EO260123. Published on 20 April 2026.
Text © 2026. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.
  •  

Mediterranean Mussel Farming Could Collapse by 2050

Four small docks overlook a waterfront. In the distance, wooden structures, shellfish farms, are visible in the water. The sky is pale.
Source: Earth’s Future

Greenhouse gas emissions are heating our atmosphere and oceans, and turning seawater more acidic. One of the myriad expected impacts of these conditions is a reduction in farming yields of shellfish, such as oysters and mussels. Coastal communities worldwide rely on these organisms for their economies and as a major food supply. However, exactly how climate change will affect oyster and mussel farming is not yet clear.

Using a novel experimental setup, Pernet et al. report new projected yields of oyster and mussel farming in the Mediterranean Sea for the years 2050, 2075, and 2100. Their results suggest that by 2050, yields of both shellfish will drop dramatically, with mussel production perhaps collapsing altogether.

Most prior studies have assessed shellfish in tank experiments under fairly idealized conditions that do not adequately reflect real-world aquaculture settings. This research team took a different approach. They developed a novel system for exposing oysters and mussels in tanks to realistic conditions using water pumped in from the sea, meaning the animals would experience fluctuations in acidity, temperature, and nutrients similar to those experienced by shellfish on nearby farms.

The researchers set up 12 experimental tanks on the French Mediterranean coast in the Thau lagoon, where shellfish farming is key for the local economy. In three tanks, oysters and mussels were exposed directly to pumped-in seawater under present, ambient conditions. The rest of the tanks received seawater that was first warmed and acidified in accordance with widely accepted climate projections for 2050, 2075, and 2100, with three tanks for each year.

The survival rate of oysters in the tanks with predicted 2100 conditions dropped by 7% compared to present rates, and their growth rate dropped by 40%. These results suggest that yields of farmed oysters in the Mediterranean could drop severely over the next several decades.

The mussels fared even worse. In fact, compared to oysters, mussels have a lower range of water temperatures in which they can survive, and the upper limit is already being exceeded in some summertime Mediterranean waters, leading to mass-mortality events. In the experimental tanks under present conditions, mussel mortality was about 40%, and nearly all mussels died under predicted 2050 conditions.

On the basis of these findings, the researchers call for the urgent development of strategies to protect Mediterranean shellfish farming, such as relocating mussel-farming operations to the cooler waters of open seas or developing cofarming with algae to increase resilience to climate change. (Earth’s Future, https://doi.org/10.1029/2025EF005992, 2025)

—Sarah Stanley, Science Writer

The logo for the United Nations Sustainable Development Goal 14 is at left. To its right is the following text: The research reported here supports Sustainable Development Goal 14. 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.
A photo of a telescope array appears in a circle over a field of blue along with the Eos logo and the following text: Support Eos’s mission to broadly share science news and research. Below the text is a darker blue button that reads “donate today.”
Citation: Stanley, S. (2026), Mediterranean mussel farming could collapse by 2050, Eos, 107, https://doi.org/10.1029/2026EO260121. Published on 17 April 2026.
Text © 2026. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.
  •  
❌