Star quality: telescope captures Sun in greatest detail ever

Yahoo – AFP, Ivan Couronne, January 31, 2020

'Boiling' plasma that covers the Sun is seen in the highest-ever resolution images
of the star, taken by the new Daniel K. Inouye Solar Telescope (AFP Photo/HO)

Washington (AFP) - A huge telescope built on the peak of a Hawaiian island has produced pictures of the Sun's surface in unprecedented detail, revealing boiling plasma cells the size of Texas.

For the telescope's director, that's only just the beginning.

The Sun is a giant ball of plasma (electrified gas) that has been observed from Earth for centuries from telescopes, and via satellites for decades.

But the resolution has been limited: the Japanese space telescope Hinotori had a mirror of 20 inches (50 centimeters).

The new Daniel K. Inouye Solar Telescope on the island of Maui has a 13-foot (four meters) mirror, the world's largest for a solar telescope.

"These images have the highest resolution that you've ever seen," said Thomas Rimmele, the telescope's director.

"We now see structures that we suspected would be there, based on computer models, but we never had the resolution to really see them," added the 60-year-old German astronomer.

Images first published Wednesday show a pattern of boiling plasma covering the Sun in cell-like structures. These are the result of violent motions transporting heat from the star's interior to its surface.

The hot plasma rises in the bright center of the cells, cools and then sinks below the surface in a process called convection.

The telescope came online on December 10 after nine years of construction.

Hot plasma rises in the bright center of the cells, cools and then sinks below the 

surface in a process called convection (AFP Photo/HO)

"It was a really emotional moment, I was really happy," said Rimmele, who joined the project 25 years ago before eventually becoming its director. "It's my life's work."

Since the telescope focuses sunlight over a small area, it produces an enormous amount of heat.

"It gets really hot there, you can put metal there and it melts within a very short time," said Rimmele.

Corona and sunspots

It will take six more months to install additional scientific instruments and make the telescope fully operational.

Ultimately, the goal is to measure the magnetic fields in the Sun's atmosphere, and in particular in its corona, its outermost area that can be distinguished during an eclipse.

The magnetic fields govern solar flares that can affect air travel, disrupt satellite communications as well as bring down power grids and disable GPS, a relatively common event.

Mapping the Sun will thus help scientists deepen their understanding of these magnetic fields that regulate space weather, allowing us to anticipate storms and turn off sensitive equipment ahead of time.

The telescope has launched at an exciting time for astronomers: the Sun is about to enter a new 11-year cycle, in which it will start to produce new sunspots.

It is currently at the low ebb of its cycle and no spots are visible.

"That is the goal, to publish a close up image, highest resolution image ever of a sunspot," said Rimmele.

Tea drinkers may have lower skin cancer risk

Fri May 4, 2007 2:07PM EDT

NEW YORK (Reuters Health) - People who unwind with a cup of tea every night may have a lower risk of two common forms of skin cancer, new research suggests.

IIn a study of nearly 2,200 adults, researchers found that tea drinkers had a lower risk of developing squamous cell or basal cell carcinoma, the two most common forms of skin cancer.

Men and women who had ever been regular tea drinkers -- having one or more cups a day -- were 20 percent to 30 percent less likely to develop the cancers than those who didn't drink tea.

The effect was even stronger among study participants who'd been tea fans for decades, as well as those who regularly had at least two cups a day, according to findings published in the Journal of the American Academy of Dermatology.

However, the findings do not mean it's okay to bake in the sun as long as you have a cup of tea afterward. The researchers found no evidence that tea drinking lowered skin cancer risk in people who'd accumulated painful sunburns in the past.

Nor did the study look at the relationship between tea drinking and malignant melanoma, the least common but most deadly form of skin cancer.

Still, the findings support the theory that tea antioxidants may limit the damage UV radiation inflicts on the skin, according to the study authors, led by Dr. Judy R. Rees of Dartmouth Medical School in Lebanon, New Hampshire.

In particular, a tea antioxidant known as EGCG has been shown to reduce burning on UV-exposed skin.

The current findings are based on interviews with 770 New Hampshire residents with basal cell carcinoma, 696 with squamous cell carcinoma, and 715 cancer-free men and women the same age.

Tea consumption was linked to a lower skin cancer risk, even with factors such as age, skin type and history of severe burns considered. However, tea drinkers who'd suffered multiple painful burns in the past did not have a lower risk of skin cancer.

It's possible, the researchers explain, that the antioxidants in tea are enough to limit skin damage caused by moderate sun exposure, but not the "more extreme" effects of sun exposure, such as cancer-promoting damage to the DNA in skin cells.

SOURCE: Journal of the American Academy of Dermatology, May 2007.

More vitamin D can put more pep in seniors' steps

By Charnicia Huggins Tue Jun 26, 12:20 PM ET

Yahoo.com

NEW YORK (Reuters Health) - Declining physical performance among some Dutch seniors may not be a simple consequence of aging, it may actually be due to a vitamin D deficiency, results of a new study suggest.

"Physicians and the general public should be made more aware of the high prevalence of vitamin D deficiency and insufficiency, and more effort should be concentrated on the early detection and treatment of people with suboptimal levels of vitamin D," study co-author Dr. Paul Lips, of VU University Medical Center in Amsterdam, and his colleagues write.

Previous research has shown that low vitamin D status is not uncommon among seniors, which may be explained by their decreased exposure to sunshine, reduced dietary consumption of vitamin D, and reduced capacity to naturally synthesize the vitamin. This deficiency is known to result in bone loss and fractures, among other bone and muscle-related problems.

The extent to which an individual's vitamin D status can affect his or her physical performance, however, has not been as well explored.

To investigate, Lips and his colleagues analyzed data on 979 seniors, 65 years or older, who were involved in the ongoing Longitudinal Aging Study Amsterdam.

They found that the study participants' vitamin D status was indeed associated with their physical performance, even after the seniors' age, the presence of chronic diseases, extent of alcohol consumption and various other factors were taken into account, they report in the Journal of Clinical Endocrinology & Metabolism.

For example, nearly half (47 percent) of the seniors had low vitamin D levels at the start of the study, and their deficiency was associated with poorer physical performance than their peers. Over the 3-year study, these vitamin D-deficient adults were also twice as likely as their peers to exhibit a decline in physical performance, such as taking longer to rise from a sitting position.

In light of these findings, "public health strategies should be aimed at this group," the researchers conclude.

The findings can also be generalized to other groups of older Dutch Caucasians, as well as to younger people, who may simply be better able to compensate for their vitamin D deficiency and subsequent decline in physical performance.

Vitamin D deficiency is not unique to the Dutch population, however. Dr. Nancy S. Wellman, a spokesperson for the American Society for Nutrition, told Reuters Health that "vitamin D is one of the most common shortfall nutrients in diets of older Americans."

"It is not found naturally in many foods," she explained.

To address this problem, Wellman, a professor and director of the National Resource Center on Nutrition, Physical Activity & Aging, at Florida International University, advises seniors to drink milk or orange juice that is fortified with vitamin D and calcium, since "both are needed for bone health."

SOURCE: Journal of Clinical Endocrinology & Metabolism, online June 2007