This discovery is based on three decades of Neptune observations captured by NASA’s Hubble Space Telescope and the W. M. Keck Observatory in Hawaii, as well as data from the Lick Observatory in California.

The link between Neptune and solar activity is surprising to planetary scientists because Neptune is our solar system’s farthest major planet and receives sunlight with about 0.1% of the intensity Earth receives. Yet Neptune’s global cloudy weather seems to be driven by solar activity, and not the planet’s four seasons, which each last approximately 40 years.

At present, the cloud coverage seen on Neptune is extremely low, with the exception of some clouds hovering over the giant planet’s south pole. A University of California (UC) Berkeley-led team of astronomers discovered that the abundance of clouds normally seen at the icy giant’s mid-latitudes started to fade in 2019.

“I was surprised by how quickly clouds disappeared on Neptune,” said Imke de Pater, emeritus professor of astronomy at UC Berkeley and senior author of the study. “We essentially saw cloud activity drop within a few months,” she said.

“Even now, four years later, the most recent images we took this past June still show the clouds haven’t returned to their former levels,” said Erandi Chavez, a graduate student at the Center for Astrophysics | Harvard-Smithsonian (CfA) in Cambridge, Massachusetts, who led the study when she was an undergraduate astronomy student at UC Berkeley. “This is extremely exciting and unexpected, especially since Neptune’s previous period of low cloud activity was not nearly as dramatic and prolonged.”

To monitor the evolution of Neptune’s appearance, Chavez and her team analyzed Keck Observatory images taken from 2002 to 2022, the Hubble Space Telescope archival observations beginning in 1994, and data from the Lick Observatory in California from 2018 to 2019.

In recent years, the Keck observations have been complemented by images taken as part of the Twilight Zone program and by Hubble’s Outer Planet Atmospheres Legacy (OPAL) program.

The images reveal an intriguing pattern between seasonal changes in Neptune’s cloud cover and the solar cycle — the period when the Sun’s magnetic field flips every 11 years as it becomes more tangled like a ball of yarn. This is evident in the increasing number of sunspots and increasing solar flare activity. As the cycle progresses, the Sun’s tempestuous behavior builds to a maximum, until the magnetic field beaks down and reverses polarity. Then the Sun settles back down to a minimum, only to start another cycle.

When it’s stormy weather on the Sun, more intense ultraviolet (UV) radiation floods the solar system. The team found that two years after the solar cycle’s peak, an increasing number of clouds appear on Neptune. The team further found a positive correlation between the number of clouds and the ice giant’s brightness from the sunlight reflecting off it.

“These remarkable data give us the strongest evidence yet that Neptune’s cloud cover correlates with the Sun’s cycle,” said de Pater. “Our findings support the theory that the Sun’s UV rays, when strong enough, may be triggering a photochemical reaction that produces Neptune’s clouds.”

Scientists discovered the connection between the solar cycle and Neptune’s cloudy weather pattern by looking at 2.5 cycles of cloud activity recorded over the 29-year span of Neptunian observations. During this time, the planet’s reflectivity increased in 2002 then dimmed in 2007. Neptune became bright again in 2015, then darkened in 2020 to the lowest level ever observed, which is when most of the clouds went away.

The changes in Neptune’s brightness caused by the Sun appear to go up and down relatively in sync with the coming and going of clouds on the planet. However there is a two-year time lag between the peak of the solar cycle and the abundance of clouds seen on Neptune. The chemical changes are caused by photochemistry, which happens high in Neptune’s upper atmosphere and takes time to form clouds.

“It’s fascinating to be able to use telescopes on Earth to study the climate of a world more than 2.5 billion miles away from us,” said Carlos Alvarez, staff astronomer at Keck Observatory and co-author of the study. “Advances in technology and observations have enabled us to constrain Neptune’s atmospheric models, which are key to understanding the correlation between the ice giant’s climate and the solar cycle.”

However, more work is necessary. For example, while an increase in UV sunlight could produce more clouds and haze, it could also darken them, thereby reducing Neptune’s overall brightness. Storms on Neptune rising up from the deep atmosphere affect the cloud cover, but are not related to photochemically produced clouds, and hence may complicate correlation studies with the solar cycle. Continued observations of Neptune are also needed to see how long the current near-absence of clouds will last.

The research team continues to track Neptune’s cloud activity. “We have seen more clouds in the most recent Keck images that were taken during the same time NASA’s James Webb Space Telescope observed the planet; these clouds were in particular seen at northern latitudes and at high altitudes, as expected from the observed increase in the solar UV flux over the past approximately 2 years,” said de Pater.

The combined data from Hubble, the Webb Space Telescope, Keck Observatory, and the Lick Observatory will enable further investigations into the physics and chemistry that lead to Neptune’s dynamic appearance, which in turn may help deepen astronomers’ understanding not only of Neptune, but also of exoplanets, since many of the planets beyond our solar system are thought to have Neptune-like qualities.

Scientists have long known that caloric restriction — intentionally consuming far less calories than normal without becoming malnourished — improves health in later life and may even extend life. However, studies in mice show that caloric restriction really needs to be maintained throughout life to achieve this impact, and the health benefits disappear when a normal diet is resumed. Dr Houseley’s new research conducted in yeast suggests an alternative to calorie restriction can lead to improved health through the lifecycle.

“We show that diet in early life can switch yeast onto a healthier trajectory. By giving yeast a different diet without restricting calories we were able to suppress senescence, when cells no longer divide, and loss of fitness in aged cells.” Said Dr Dorottya Horkai, lead researcher on the study.

Rather than growing yeast on their usual glucose-rich diet, the researchers swapped their diet to galactose and observed that many molecular changes which normally accompany ageing did not occur. The cells grown on galactose remained just as fit as young cells even late in life, despite not living any longer, showing that the period of ill-health towards the end of life was dramatically reduced.

“Crucially, the dietary change only works when cells are young, and actually diet makes little difference in old yeast. It is hard to translate what youth means between yeast and humans, but all these studies point to the same trend — to live a long and healthy life, a healthy diet from an early age makes a difference.” explains Dr Houseley.

Yeast are good model organisms for studying ageing as they share many of the same cellular machinery as animals and humans. This avenue of research in yeast helps us to seek a more achievable way to improve healthy ageing though diet compared to sustained and severe calorie restriction, although more research is needed.

“We envision this device will be used by individuals who need or desire information to be transmitted to them privately and in a way that can be seamlessly integrated into clothing or other wearables,” said Marcia O’Malley (@MarcieOMalley), Chair of the Department of Mechanical Engineering at Rice University and an author of the study.

The wearables may benefit amputees who use prosthetic limbs, people with hearing loss, and specialists such as surgeons, pilots, and soldiers who are inundated with visual and auditory information.

Visual and auditory cues like a flashing light on a dashboard or the ping of a new text message can effectively transmit information. However, many people are overwhelmed by such cues in their daily lives — and with too many notifications conveyed the same way, information can get lost in the clutter. “Haptics,” or touch-based stimuli, which include hot or cold sensations or cues based on pressure applied to the skin, can offer an alternative.

But while devices that produce visual cues or sounds are prevalent in everyday life, devices that use haptic cues are still uncommon since they usually require bulky hardware that weighs down the wearer.

To overcome this obstacle, the Rice University researchers developed a light, comfortable wearable device from textile materials that can be worn on a user’s arm. The team tested the device by measuring forces applied to the user as a function of pressure and the shape of the wearable — a task that proved somewhat challenging since different users had different experiences with cues from the same device, said Barclay Jumet (@JUMETkinmecrazy), a PhD candidate in mechanical engineering and the lead author of the study.

“Every person has a differently shaped arm, a different perception of what “feels good” in terms of the forces applied and the timing of the forces, and different capabilities in responding to the type of haptic cues we delivered,” said Jumet. “Fortunately, our textile-based platform is easily tailorable and adjustable to a range of body types and sizes.”

After testing the performance of their haptic textile sleeves in a lab-based study involving human participants, the researchers set out to see how well these devices could help users navigate in a real-world scenario. They integrated two of the sleeves into a shirt and completed the ensemble with a textile belt where they attached auxiliary components, making the device portable. Next, an experimenter sent cues to the user wearing the device, directing them where to walk for one kilometer.

“We were impressed that the user was able to navigate the streets of Houston and subsequently trace 50-meter-long Tetris pieces on an open field with 100% accuracy in receiving and interpreting navigational haptic cues,” said Daniel Preston (@ProfDanPreston), an assistant professor of mechanical engineering and the corresponding author of the study.

In another navigation test, the participant again interpreted the cues with total accuracy, this time while riding an electric scooter over paved bricks, concrete sidewalks, and graveled paths.

“Further development will seek to improve the ability to convey even more complex cues that remain easily and naturally discerned by the user,” said Preston.

Not only is it already making a difference to kākāpō survival, but establishing sequencing methods to work with populations under threat is also likely to be the foundation for the future of endangered wildlife science in New Zealand and the rest of the world.

The state-of-the-art methods developed by Dr. Joseph Guhlin (University of Otago ) and an international team to study kākāpō has revealed important aspects of kākāpō biology. The methods, reusable code, and pipeline is a blueprint and tool for conservation genomics in other species, especially intensively managed species. This has massive implications.

Dr. Guhlin’s work over the last year have two very significant outcomes:

• an in-depth understanding of kākāpō biology that simply would not be possible without genomics
• high-quality code and reusable pipeline — allowing other researchers to rapidly integrate these methods into their own work — which has significantly advanced New Zealand’s genomic capability.

This has given researchers the tools needed to identify specific genetic characteristics that are crucial to survival.

“Using technology created by Google, we have achieved what is likely the highest quality variant dataset for any endangered species in the world. This dataset is made available, through DOC and Ngai Tahu, for future researchers working with kākāpō,” Dr Guhlin said.

Department of Conservation’s Science Advisor for kākāpō Recovery, Dr. Andrew Digby, believes the genetic tools this study provides will make an immense difference to kākāpō conservation.

“kākāpō suffer from disease and low reproductive output, so by understanding the genetic reasons for these problems, we can now help mitigate them. It gives us the ability to predict things like kākāpō chick growth and susceptibility to disease, which changes our on-the-ground management practices and will help improve survival rates.”

While the study marks the beginning of a new era of kākāpō conservation genetics, Dr Digby acknowledges what it means for the future of all threatened species.

“The Kakapo125+ project is a great example of how genetic data can assist population growth. The novel genetic and machine learning tools developed can be applied to improve the productivity and survival of other taonga under conservation management.”