University of Cambridge

Leber hereditary optic neuropathy (LHON) affects around 2,500 people in the United Kingdom.  It causes rapidly progressive loss of vision in both eyes. Within weeks of onset, an affected individual reaches the legal threshold to be considered as severely sight impaired (blind). The condition tends to affect young men, with a peak age of onset between the ages of 15 and 35 years old, but women can also be affected and the loss of vision can occur at any age.  The prognosis is poor, with only around one in 10 affected individuals experiencing some spontaneous visual improvement, which is invariably partial. LHON is caused by the loss of retinal ganglion cells, specialised nerve cells in the innermost layer of the retina. The projections, or ‘axons’, from these cells converge to form the optic nerve, the cable that transmits visual information from the eye to the brain. Once these retinal ganglion cells are lost, the damage becomes irreversible. LHON is primarily caused by genetic defects within the mitochondrial genome, which is transmitted down the maternal line.  In 2011, the journal Brain published the results of a landmark randomised placebo-controlled trial of the drug idebenone to treat LHON. The RHODOS trial was led by Patrick Chinnery, at the time a researcher at Newcastle University and now Professor of Neurology at the University of Cambridge. It found some potential benefit in a subgroup of patients. However, treatment with idebenone was only given for six months, and it was not clear whether there was any benefit in treating individuals who had been affected for more than one year. “At the time, we had only anecdotal evidence that idebenone would work for patients with LHON,” said Professor Chinnery. “Our clinical trial was the first strong evidence that it could help stabilise vision in some patients. It was an important step towards providing a new treatment.” One of Professor Chinnery’s collaborators on the RHODOS trial was Patrick Yu-Wai-Man, Professor of Ophthalmology at the University of Cambridge, who led the follow-up LEROS trial. This assessed the efficacy and safety of idebenone treatment in patients with LHON up to five years after symptom onset and over a treatment period of 24 months. This second trial found that the drug can help stabilise vision in some patients and, in certain cases, may even lead to improvement when treatment is provided within five years of vision being affected. These studies provided crucial evidence to support the use of idebenone to treat LHON patients. The drug was licenced for limited use by patients in Scotland, Wales and Northern Ireland and it has now been approved by NICE for use in patients aged 12 years and over in England. Professor Yu-Wai-Man said: “LHON causes devastating visual loss and it is a life-changing diagnosis for the affected individual and their family. England is now in line with the rest of the United Kingdom with idebenone now available through the NHS. This will come as a great relief to the LHON community in this country bringing hope to those who have experienced significant visual loss from this mitochondrial genetic disorder.” The development has been welcomed by charities that have been arguing for idebenone to be made available across the UK. A LHON Society spokesperson said: “This is a critical step towards full access to idebenone for patients, that may alleviate some of the impacts of LHON.” Katie Waller, Head of Patient Programmes at The Lily Foundation, a charity that supports patients affected by mitochondrial diseases, said: “This is a huge win for the mito community and we’re proud to have been a key stakeholder throughout the process. While it isn’t a cure, this treatment offers real potential for patients to preserve or improve vision, giving the chance to regain independence, confidence and a better quality of life.” Idebenone will not work for everyone, and responses vary from person to person. LHON patients are encouraged to speak with the healthcare professional responsible for their care to understand whether idebenone is the right treatment for them. The National Institute for Health and Care Excellence (NICE) has today announced the approval of a new treatment for a form of hereditary blindness for use on the NHS in England. Cambridge researchers played a pivotal role in providing the evidence that led to this important development. This will bring hope to those who have experienced significant visual loss from this mitochondrial genetic disorderPatrick Yu-Wai-ManPeopleImages (Getty)Man undergoing an eye examination The text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright ©University of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms. Yes

Leber hereditary optic neuropathy (LHON) affects around 2,500 people in the United Kingdom.  It causes rapidly progressive loss of vision in both eyes. Within weeks of onset, an affected individual reaches the legal threshold to be considered as severely sight impaired (blind). The condition tends to affect young men, with a peak age of onset between the ages of 15 and 35 years old, but women can also be affected and the loss of vision can occur at any age.  The prognosis is poor, with only around one in 10 affected individuals experiencing some spontaneous visual improvement, which is invariably partial. LHON is caused by the loss of retinal ganglion cells, specialised nerve cells in the innermost layer of the retina. The projections, or ‘axons’, from these cells converge to form the optic nerve, the cable that transmits visual information from the eye to the brain. Once these retinal ganglion cells are lost, the damage becomes irreversible. LHON is primarily caused by genetic defects within the mitochondrial genome, which is transmitted down the maternal line.  In 2011, the journal Brain published the results of a landmark randomised placebo-controlled trial of the drug idebenone to treat LHON. The RHODOS trial was led by Patrick Chinnery, at the time a researcher at Newcastle University and now Professor of Neurology at the University of Cambridge. It found some potential benefit in a subgroup of patients. However, treatment with idebenone was only given for six months, and it was not clear whether there was any benefit in treating individuals who had been affected for more than one year. “At the time, we had only anecdotal evidence that idebenone would work for patients with LHON,” said Professor Chinnery. “Our clinical trial was the first strong evidence that it could help stabilise vision in some patients. It was an important step towards providing a new treatment.” One of Professor Chinnery’s collaborators on the RHODOS trial was Patrick Yu-Wai-Man, Professor of Ophthalmology at the University of Cambridge, who led the follow-up LEROS trial. This assessed the efficacy and safety of idebenone treatment in patients with LHON up to five years after symptom onset and over a treatment period of 24 months. This second trial found that the drug can help stabilise vision in some patients and, in certain cases, may even lead to improvement when treatment is provided within five years of vision being affected. These studies provided crucial evidence to support the use of idebenone to treat LHON patients. The drug was licenced for limited use by patients in Scotland, Wales and Northern Ireland and it has now been approved by NICE for use in patients aged 12 years and over in England. Professor Yu-Wai-Man said: “LHON causes devastating visual loss and it is a life-changing diagnosis for the affected individual and their family. England is now in line with the rest of the United Kingdom with idebenone now available through the NHS. This will come as a great relief to the LHON community in this country bringing hope to those who have experienced significant visual loss from this mitochondrial genetic disorder.” The development has been welcomed by charities that have been arguing for idebenone to be made available across the UK. A LHON Society spokesperson said: “This is a critical step towards full access to idebenone for patients, that may alleviate some of the impacts of LHON.” Katie Waller, Head of Patient Programmes at The Lily Foundation, a charity that supports patients affected by mitochondrial diseases, said: “This is a huge win for the mito community and we’re proud to have been a key stakeholder throughout the process. While it isn’t a cure, this treatment offers real potential for patients to preserve or improve vision, giving the chance to regain independence, confidence and a better quality of life.” Idebenone will not work for everyone, and responses vary from person to person. LHON patients are encouraged to speak with the healthcare professional responsible for their care to understand whether idebenone is the right treatment for them. The National Institute for Health and Care Excellence (NICE) has today announced the approval of a new treatment for a form of hereditary blindness for use on the NHS in England. Cambridge researchers played a pivotal role in providing the evidence that led to this important development. This will bring hope to those who have experienced significant visual loss from this mitochondrial genetic disorderPatrick Yu-Wai-ManPeopleImages (Getty)Man undergoing an eye examination The text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright ©University of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms. Yes

Visible only from the Southern hemisphere, the system is made up of the binary Alpha Centauri A and Alpha Centauri B, both Sun-like stars, and the faint red dwarf star Proxima Centauri. Alpha Centauri A is the third brightest star in the night sky. While there are three confirmed planets orbiting Proxima Centauri, the presence of other worlds surrounding Alpha Centauri A and Alpha Centauri B has proved difficult to confirm, because the stars are so bright, close, and move across the sky quickly. Now, observations from Webb’s Mid-Infrared Instrument (MIRI) are providing the strongest evidence to date of a gas giant orbiting Alpha Centauri A. The results, from an international team including researchers from the University of Cambridge, have been accepted for publication in two papers in The Astrophysical Journal Letters. If confirmed, the planet would be the closest to Earth that orbits in the habitable zone of a Sun-like star. However, because the planet candidate is a gas giant, scientists say it would not support life as we know it. Several rounds of observations by Webb, analysis by the research team, and computer modelling helped determine that the source seen in Webb’s image is likely to be a planet, and not a background object (like a galaxy), a foreground object (a passing asteroid), or another image artefact. “Webb was designed and optimised to find the most distant galaxies in the universe. The team had to come up with a custom observing sequence just for this target, and their extra effort paid off spectacularly,” said Charles Beichman, NASA’s Jet Propulsion Laboratory and the NASA Exoplanet Science Institute at Caltech, co-first author on the new papers. The first observations of the system took place in August 2024. While extra brightness from the nearby companion star Alpha Centauri B complicated the analysis, the team was able to subtract out the light from both stars to reveal an object over 10,000 times fainter than Alpha Centauri A, separated from the star by about two times the distance between the Sun and Earth. While the initial detection was exciting, the research team needed more data to come to a firm conclusion. However, additional observations of the system in February 2025 and April 2025 did not reveal any objects like the one identified in August 2024. “We were faced with the case of a disappearing planet! To investigate this mystery, we used computer models to simulate millions of potential orbits, incorporating the knowledge gained when we saw the planet, as well as when we did not,” said co-first author Aniket Sanghi of the California Institute of Technology. In these simulations, the team took into account both the 2019 sighting of a potential exoplanet candidate by the European Southern Observatory’s Very Large Telescope, the new data from Webb, and considered orbits that would be gravitationally stable in the presence of Alpha Centauri B, meaning the planet wouldn’t get flung out of the system. The researchers say a non-detection in the second and third round of observations with Webb wasn’t surprising. “We found that in half of the possible orbits simulated, the planet moved too close to the star and wouldn’t have been visible to Webb in both February and April 2025,” said Sanghi. In addition to these simulations, the Cambridge members of the research team analysed the Webb data to search for any signs of a type of cosmic dust, known as exozodiacal dust, around Alpha Centauri A. This cloud of dust, produced by objects such as comets and asteroids breaking apart, forms a faint, glowing disc around a star. “Exozodiacal dust helps us learn about the architecture and evolution of planetary systems,” said co-author Professor Mark Wyatt from Cambridge’s Institute of Astronomy. “But it’s also important when searching for rocky planets, since dust in the habitable zone of a star can obscure or mimic planetary signals.” No dust was detected in these observations, however, the team showed they were sensitive to dust levels an order of magnitude lower than any previous measurement, which could be valuable for future planet searches around this star. “This observation shows how deeply Webb can probe the dust environment of the nearest Sun-like stars,” said co-author Dr Max Sommer, also from Cambridge’s Institute of Astronomy. “We can now explore exozodiacal dust at levels not much higher than those in our own Solar System, tapping into a whole new way of looking at other star systems.” Based on the brightness of the planet in the mid-infrared observations and the orbit simulations, the researchers say it could be a gas giant approximately the mass of Saturn orbiting Alpha Centauri A in an elliptical path varying between one to two times the distance between Sun and Earth. If confirmed, the potential planet seen in the Webb image of Alpha Centauri A would mark a new milestone for exoplanet imaging efforts. Of all the directly imaged exoplanets, this would be the closest to its star seen so far. It’s also the most similar in temperature and age to the giant planets in our solar system, and the nearest to Earth. “Its very existence in a system of two closely separated stars would challenge our understanding of how planets form, survive, and evolve in chaotic environments,” said Sanghi. The James Webb Space Telescope is an international programme led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency). Reference: Charles Beichman, Aniket Sanghi et al. ‘Worlds Next Door: A Candidate Giant Planet Imaged in the Habitable Zone of α Cen A. I. Observations, Orbital and Physical Properties, and Exozodi Upper Limits’. The Astrophysical Journal Letters (in press). arXiv:2508.03812v1 Aniket Sanghi, Charles Beichman et al. ‘Worlds Next Door: A Candidate Giant Planet Imaged in the Habitable Zone of  α Cen A. II. Binary Star Modeling, Planet and Exozodi Search, and Sensitivity Analysis’. The Astrophysical Journal Letters (in press). arXiv:2508.03812 Adapted from a NASA press release. Astronomers using the NASA/ESA/CSA James Webb Space Telescope have found strong evidence of a giant planet orbiting a star in the stellar system closest to our own Sun. At just four light-years away from Earth, the Alpha Centauri triple star system has long been a target in the search for worlds beyond our solar system. NASA, ESA, CSA, STScI, Robert L. Hurt (Caltech/IPAC)Artist's impression of a gas giant orbiting Alpha Centauri A. The text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright ©University of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms. Yes

In a study published in the journal Physical Review E, researchers have found that these insects begin their loud daily serenades when the sun is precisely 3.8 degrees below the horizon: a consistent marker of early morning light known as civil twilight. The research, carried out by scientists from India, the UK and Israel, analysed several weeks of field recordings taken at two locations near Bangalore in India. Using tools from physics typically applied to the study of phase transitions in materials, the team uncovered a regularity in how cicadas respond to subtle changes in light. “We’ve long known that animals respond to sunrise and seasonal light changes,” said co-author Professor Raymond Goldstein, from Cambridge’s Department of Applied Mathematics and Theoretical Physics. “But this is the first time we’ve been able to quantify how precisely cicadas tune in to a very specific light intensity — and it’s astonishing.” The crescendo of cicada song — familiar to anyone who has woken up early on a spring or summer morning — takes only about 60 seconds to build, the researchers found. Each day, the midpoint of that build-up occurs at nearly the same solar angle, regardless of the exact time of sunrise. In practical terms, that means cicadas begin singing when the light on the ground has reached a specific threshold, varying by just 25% during that brief transition. To explain this level of precision, the team developed a mathematical model inspired by magnetic materials, in which individual units, or spins, align with an external field and with each other. Similarly, their model proposes that cicadas make decisions based both on ambient light and the sounds of nearby insects, like individuals in an audience who start clapping when others do. “This kind of collective decision-making shows how local interactions between individuals can produce surprisingly coordinated group behaviour,” said co-author Professor Nir Gov from the Weizmann Institute, who is currently on sabbatical in Cambridge. The field recordings were made by Bangalore-based engineer Rakesh Khanna, who carries out cicada research as a passion project. Khanna collaborated with Goldstein and Dr Adriana Pesci at Cambridge’s Department of Applied Mathematics and Theoretical Physics. “Rakesh’s observations have paved the way to a quantitative understanding of this fascinating type of collective behaviour,” said Goldstein. “There’s still much to learn, but this study offers key insights into how groups make decisions based on shared environmental cues.” The study was partly supported by the Complex Systems Fund at the University of Cambridge. Raymond Goldstein is the Alan Turing Professor of Complex Physical Systems and a Fellow of Churchill College, Cambridge. Reference: Khanna, R.A., Goldstein, R.E., Pesci, A.I., & Gov, N.S. ‘Photometric Decision-Making During the Dawn Choruses of Cicadas.’ Physical Review E (2025). DOI: 10.1103/4y4d-p32q Cicadas coordinate their early morning choruses with remarkable precision, timing their singing to a specific level of light during the pre-dawn hours. UA-Visions via Getty ImagesAnnual cicada The text in this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Images, including our videos, are Copyright ©University of Cambridge and licensors/contributors as identified. All rights reserved. We make our image and video content available in a number of ways – on our main website under its Terms and conditions, and on a range of channels including social media that permit your use and sharing of our content under their respective Terms. Yes