Monday, June 23, 2025

Sun’s fury may change the weather on distant worlds — and maybe even ours

The Hebrew University of Jerusalem

Jerusalem, Israel — A new study led by scientists from the Hebrew University of Jerusalem, NASA, the Florida Institute of Technology, the Barcelona Supercomputing Center, and the University of Oxford has uncovered a connection between solar flares — sudden outbursts of radiation from stars — and short-term weather patterns on distant Earth-like planets.

Published in The Astronomical Journal, the study offers the clearest evidence yet that space weather — particularly flares from a planet’s host star — can cause measurable changes in a planet’s climate within just days of an event. These findings provide important clues about the habitability of exoplanets and may even help refine how we understand short-term atmospheric shifts on Earth.

“This study highlights an underexplored but important solar-climate link,” said Dr. Assaf Hochman, from the Institute of Earth Sciences at Hebrew University. “While anthropogenic greenhouse gases primarily drive long-term climate change, we now see that short-term solar variability can also play a role in modulating regional climate behavior.”

The international team — including Dr. Assaf Hochman, Dr. Howard Chen, Dr. Paolo De Luca, and Dr. Thaddeus D. Komacek — used advanced 3D General Circulation Models to simulate how sudden flares from host stars affect the climate on tidally-locked exo-Earths such as TRAPPIST-1e, a planet that always shows the same face to its sun.

Their results reveal a chain reaction:

Upper atmospheric cooling occurs quickly after a flare, driven by radiative emissions from molecules like NO and CO₂.
Simultaneously, lower atmospheric warming happens due to increases in greenhouse-like gases such as H₂O and N₂O.
Wind speeds in the middle atmosphere can intensify dramatically — surging to over 140 km/h on the dark, night side of the planet.

What It Means for Earth — and Beyond

While the main focus was on distant worlds, the study opens up provocative possibilities for Earth’s climate systems too.

The patterns observed suggest that solar activity may temporarily alter a planet’s general atmospheric circulation. This isn’t about long-term climate shifts, but rather short-lived regional anomalies — the kind that could be especially noticeable in already volatile weather zones.

The research emphasizes that while solar flares aren’t a major driver of Earth’s long-term climate compared to human activity, their effects are real, detectable, and worth factoring into future atmospheric models. This is particularly true when considering regions sensitive to abrupt changes in temperature and wind.

The study also underscores that stars don’t just warm their planets — they can stir up the weather too. Understanding these interactions is crucial to assessing which exoplanets might truly be capable of supporting life.

This interdisciplinary effort brought together experts in astroclimate modeling, atmospheric chemistry, and planetary science, with support from institutions across four countries and multiple NASA research centers. Their findings not only enhance our understanding of distant exoplanets but could also help us refine how we predict and prepare for solar influences here on Earth.

Journal

The Astronomical Journal

DOI

10.3847/1538-3881/add33e

Method of Research

Data/statistical analysis

Subject of Research

Not applicable

Article Title

Effects of transient stellar emissions on planetary climates of tidally-locked exo-earths

Article Publication Date

22-Jun-2025

Australian native bee honey shows medical potential in the fight against antibiotic resistance

‘Sugarbag’ honey, historically used by First Nations, could scale commercially

University of Sydney

Resistance to synthetic antibiotics poses a critical global health challenge. Various European honeybee and other natural products have been proposed as novel therapeutic agents to address this problem. However, little has been known about the potential of Australian native bee honey as an antimicrobial agent.

A study led by Dr Kenya Fernandes from the University of Sydney has now demonstrated the remarkable antimicrobial properties of honey produced by three species of native Australian stingless bees: Tetragonula carbonaria, Tetragonula hockingsi, and Austroplebeia australis.

Commonly referred to as “sugarbag bees”, the honey from these species has historically served as a food source. It is also a traditional remedy for ailments like itchy skin and sores among Indigenous communities in Australia.

The new research reveals stingless bee honey possesses antimicrobial properties that remain effective even after heat treatment and long-term storage. These distinctive features set it apart from honey from honeybees, highlighting its potential as a sustainable, natural agent for combating drug-resistant infections.

The study has been published in Applied and Environmental Microbiology, published by the American Society for Microbiology.

Dr Fernandes said: “Given the growing medical challenge of antimicrobial resistance, our findings suggest stingless bee honey could complement, or provide a valuable alternative to, synthetic antibiotics.”

Unlike honey from the European honeybee (Apis mellifera), which often relies on hydrogen peroxide for its antimicrobial effects, the honey from Australian stingless bees exhibits high levels of both hydrogen peroxide and non-peroxide activity – making it robust and versatile as a potential therapeutic agent.

The research found when hydrogen peroxide was removed the honey displayed antimicrobial activity, suggesting this is intrinsic to the honey itself.

Dr Fernandes said: “Manuka honey from honeybees displays strong non-peroxide antimicrobial activity, which is one reason why its production has been a commercial success. However, that is largely reliant on the source of its nectar from specific myrtle plants (Leptospermum).

“In contrast, the persistent antimicrobial activity of heat-treated, non-peroxide honey from stingless Australian bees across diverse locations and nectar sources suggests there is something special about these bees, rather than just nectar, that plays a critical role here.”

Co-author Professor Dee Carter said: “We discovered the antimicrobial activity is consistent across all sugarbag samples tested, unlike honeybee honey, which can vary significantly based on seasonal changes and floral sources.”

The researchers hope this consistency could enhance the potential for commercial medical applications.

However, challenges remain concerning scalability. Each stingless beehive produces about half a litre of honey a year, presenting a challenge for large-scale production.

Co-author Dr Ros Gloag said: “While the yield is small, these hives require less maintenance than traditional beehives, allowing beekeepers to manage larger numbers. With proper incentives, such as commercial value for the honey, it's feasible to cultivate more hives, providing a pathway for commercial scalability.”

Encouragingly, native stingless bee honey last year gained approval from Food Standards Australia New Zealand, paving the way for national and international commercialisation. This regulatory support holds promise for the establishment of a niche market for high-value, small-quantity products.

The antimicrobial properties of stingless bee honey have garnered attention not only for their effectiveness but also for their potential stability over time. Furthermore, earlier studies have highlighted that microbes generally do not develop resistance to honey, unlike conventional antibiotics that often operate on a singular mechanism. This offers a compelling argument for incorporating stingless bee honey into therapeutic frameworks, the researchers say.

The research team aims to explore non-peroxide activity further to understand its sources and implications.

Dr Fernandes said: “While we have yet to test the honeys against drug-resistant bacteria specifically, the presence of multiple antimicrobial factors significantly reduces the likelihood of resistance developing.”

Dr Fernandes is an Australian Research Council DECRA Fellow in the School of Life and Environmental Sciences at the University of Sydney. She is also a member of the Sydney Infectious Diseases Institute and the Centre for Drug Discovery Innovation.

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Native bee hives [VIDEO] |

Bee hives of Australian native bee species Tetragonula carbonaria.

DOWNLOAD photo of Dr Kenya Fernandes and native honeybees at this link.

RESEARCH

Fernandes, K. et al ‘Strong antimicrobial activity and unique physiochemical characteristics in honey from Australian stingless bees Tetragonula carbonaria, Tetragonula hockingsi and Austroplebeia australis’ (Applied and Environmental Microbiology 2025)
DOI: 10.1128/aem.02523-24

DECLARATION

The authors declare no competing interests. Research was supported by the NSW Bushfire Industry Recovery Package Sector Development Grant and by seed funding from Fungisphere within the Sydney Infectious Diseases Institute.