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Astronomers find hot stars peppered with massive magnetic spots



June 1 (UPI) — Astronomers have discovered giant magnetic spots on the surfaces of hot stars hidden away in stellar clusters. Scientists also found evidence of superflare events, eruptions featuring several times more energy than those observed on the surface of the sun.

The new survey of extreme horizontal branch stars, published Monday in the journal Nature Astronomy, could help scientists unravel some of the mysterious of these unusual stellar objects.

“These hot and small stars are special because we know they will bypass one of the final phases in the life of a typical star and will die prematurely,” lead researcher Yazan Momany, scientist at the INAF Astronomical Observatory of Padua in Italy, said in a news release. “In our galaxy, these peculiar hot objects are generally associated with the presence of a close companion star.”

Momany and his colleagues were surprised to find that most of the extreme horizontal branch stars they found inside the dense structures known as stellar clusters are without companions.

Using several European Southern Observatory telescopes, scientists observed several extremely hot stars inside three different stellar clusters. Their observations revealed surprisingly large levels of brightness variability over short periods of time.

“After eliminating all other scenarios, there was only one remaining possibility to explain their observed brightness variations,” said study co-author Simone Zaggia, researcher at the INAF Astronomical Observatory. “These stars must be plagued by spots!”

On the sun, spots appear dark because they’re cooler than the surrounding plasma. On the extremely hot stars described in the latest paper, the spots are hotter — and brighter — than their surroundings.

The massive magnetic spots are also bigger and more persistent than sunspots. Whereas sunspots last a matter of weeks, the massive magnetic spots found by Momany and his research partners can last for years.

Though both sunspots found on our sun and the giant spots found on extreme horizontal branch stars are quite different, they’re both fueled by magnetic fields.

While observing the massive spots, scientists also witnessed a couple of superflare events.

“They are similar to the flares we see on our own Sun, but ten million times more energetic,” said study co-author Henri Boffin, an astronomer at ESO’s headquarters in Germany. “Such behavior was certainly not expected and highlights the importance of magnetic fields in explaining the properties of these stars.”

Astronomers have spent more than half a century studying the behavior of extreme horizontal branch stars. In addition to helping astronomers understand these peculiar stars, the latest findings could also help scientists unravel the complexities of magnetic phenomena on other types of stars, including the sun.

“The bigger picture though is that changes in brightness of all hot stars — from young sun-like stars to old extreme horizontal branch stars and long-dead white dwarfs — could all be connected,” said researcher David Jones, scientist with Spain’s Canary Islands Institute of Astrophysics. “These objects can thus be understood as collectively suffering from magnetic spots on their surfaces.”

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Researchers, growers seek vanilla production in Florida



ORLANDO, Fla., Aug. 11 (UPI) — Growers and researchers in Florida hope the aromatic vanilla bean can provide a lucrative, high-margin crop for the state’s farmers.

The University of Florida is heading research into vanilla, which comes from a tropical orchid and carries a hefty price around the world.

The goal is to determine how well the plants grow in Florida’s subtropical climate, where the dominant crop — citrus — has suffered from destructive diseases and hurricanes that have shut groves and put growers out of business.

Already, the university reports that hobbyists, bakers and breweries are calling to line up more vanilla production.

“The interest in this as a new crop is huge,” said Alan Chambers, assistant professor of tropical plant genetics at the university’s research station south of Miami.

“Our biggest problem right now is growers can’t find enough plants. We have people calling and asking to buy the beans we’re growing, and we say you have to wait a couple of years.”

Chambers knows that vanilla can grow in Florida because four native species of the vanilla orchid plants exist, but none of the native types produces authentic vanilla.

So, he’s started with the most common commercial species, vanilla planifolia, the beans from which Madagascar and Mexico export in large quantities. Chambers has 150 of the plants ready to distribute to community center gardens and other growers as far north as Tampa.

Florida will never be able to compete globally for vanilla due to the cost of labor, but there’s a big demand for specialty vanilla, he said.

“We’d be looking at extremely high quality, similar to the limited vanilla production in Hawaii,” Chambers said. “We’re hearing from brewers, herbalists, bakers and aroma extractors.”

Chambers also helped a Miami area grower, attorney Abrahm Smith, obtain 800 of the vanilla plants for Smith’s small, 8-acre farm. They take up about one-quarter of an acre.

“It’s a hobby farm for me, but if vanilla works, it will be great because it has a very high-profit margin,” Smith said. “I should be able to make as much from that quarter-acre as I do from 6 acres of fruit trees we’ve planted.”

That high margin is what drove the crop to become one of Madagascar’s top exports, but the bean is not processed on the island. Much of the bean crop is processed when it reaches the United States, where it is primarily used as a food and drink flavoring.

The price of vanilla has fluctuated wildly in recent years with weather conditions in Madagascar, from $600 per 2.2 pounds of beans in 2018 to $350 for that amount in June.

The United States is the largest importer of vanilla beans. Given the high value of the crop, and Florida’s struggles with citrus, the University of Florida funded Chambers’ research with a $75,000 grant.

Chambers also advises a separate project led by private industry that collects funds from interested growers to provide thousands of the vanilla plants from a nursery in Orlando.

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Math models developed by Alan Turing help scientists explain bird behavior



Aug. 11 (UPI) — In a new study, researchers in Britain used math models developed by famed mathematician Alan Turing to figure out why flocks of long-tailed tits separate themselves into different parts of their habitat.

Many birds form what are called home range patterns, but scientists have struggled to explain why non-territorial passerine segregate themselves.

For the study, scientists at the University of Sheffield tracked the movements of long-tailed tits across the woodlands they called home. After collecting enough data for patterns to emerge, researchers used Turing-inspired models to determine what causes the segregation.

The models deployed by Sheffield researchers were similar to those Turing developed to show how patterns in nature, like stripes of a zebra or a leopard’s spots, can emerge naturally from a uniform state.

The new analysis, published this week in the Journal of Animal Ecology, showed long-tailed tits, when segregating themselves across the landscape, were less likely to avoid places where they had previously interacted with relatives.

The passerine birds, however, were more likely to steer clear of places where they’d previously encountered larger flocks. The birds also showed a preference for the center of the woodlands.

“Mathematical models help us understand nature in an extraordinary amount of ways and our study is a fantastic example of this,” Sheffield doctoral student Natasha Ellison, lead author of the new study, said in a news release.

Scientists had previously used Turing models to understand the movement patterns and distribution of territorial animals, but this is the first time the same mathematical models have helped researchers understand the spacing and movements of a non-territorial species.

“Long-tailed tits are too small to be fitted with GPS trackers like larger animals, so researchers follow these tiny birds on foot, listening for bird calls and identifying birds with binoculars,” Ellison said.

“The field work is extremely time consuming and without the help of these mathematical models these behaviors wouldn’t have been discovered,” Ellison said.

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Increasing indigenous property rights could help save the rainforest



Aug. 11 (UPI) — To protect the Amazonian rainforest, new research suggests full property rights for tribal lands be extended to Brazil’s indigenous communities.

For the study, researchers at the University California, San Diego, used satellite data of vegetation coverage in the Amazon rainforest to study deforestation patterns between 1982 and 2016. Scientists compared the results of their mapping efforts with Brazilian government records of indigenous property rights.

The analysis, detailed Tuesday in the journal Proceedings of the National Academy of Sciences, showed land owned fully and collectively by local tribes featured a 66 percent reduction in deforestation rates.

“Indigenous traditional land use, based on collective ownership, has been associated with the preservation of a land’s biodiversity,” researcher Kathryn Baragwanath, postdoctoral candidate in the political science department at UCSD, told UPI.

One study published earlier this year showed land stewardship by indigenous communities was associated with greater levels of carbon sequestration.

Baragwanath said these positive ecological impacts are strengthened when indigenous communities have the full scope of property rights and legal tools to defend tribal lands from commercial interests.

“These legal rights ensure that the boundaries can no longer be contested, the territory is registered in the national land registry, the government is constitutionally responsible for protecting the territories and the territorial resources are considered to belong to indigenous peoples,” she said.

When conducting their analysis, Baragwanath and researchers accounted for variables besides indigenous property rites — including proximity to roads, mining projects and rivers, elevation, population density and rainfall.

In Brazil, the process of gaining full property rights, called homologation, is complex — at least partially because government agencies there have been slow to review applications, researchers said.

Often, as the process plays out at a snail’s pace, commercial interests will start illegal mining or logging, so they can later argue that they’ve established “productive use of land,” researchers said.

To protect the Amazon and the region’s remaining forests, Baragwanath suggests Brazil’s government strengthen their environmental agencies.

“Public policy should focus on granting full property rights to the indigenous peoples who have not yet received their rights,” she said.

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