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The widely studied metallic asteroid known as 16 Psyche was long thought to be the exposed iron core of a small planet that failed to form during the earliest days of the solar system. But new University of Arizona-led research suggests that the asteroid might not be as metallic or dense as once thought, and hints at a much different origin story. Scientists are interested in 16 Psyche because if its presumed origins are true, it would provide an opportunity to study an exposed planetary core up close. NASA is scheduled to launch its Psyche mission in 2022 and arrive at the asteroid in 2026. UArizona undergraduate student David Cantillo is lead author of a new paper published in The Planetary Science Journal that proposes 16 Psyche is 82.5% metal, 7% low-iron pyroxene and 10.5% carbonaceous chondrite that was likely delivered by impacts from other asteroids. Cantillo and his collaborators estimate that 16 Psyche's bulk density—also known as porosity, which refers to how much empty space is found within its body—is around 35%. These estimates differ from past analyses of 16 Psyche's composition that led researchers to estimate it could contain as much as 95% metal and be much denser. "That drop in metallic content and bulk density is interesting because it shows that 16 Psyche is more modified than previously thought," Cantillo said. Rather than being an intact exposed core of an early planet, it might actually be closer to a rubble pile, similar to another thoroughly studied asteroid—Bennu. UArizona leads the science mission team for NASA's OSIRIS-REx mission, which retrieved a sample from Bennu's surface that is now making its way back to Earth. "Psyche as a rubble pile would be very unexpected, but our data continues to show low-density estimates despite its high metallic content," Cantillo said. Asteroid 16 Psyche is about the size of Massachusetts, and scientists estimate it contains about 1% of all asteroid belt material. First spotted by an Italian astronomer in 1852, it was the 16th asteroid ever discovered. "Having a lower metallic content than once thought means that the asteroid could have been exposed to collisions with asteroids containing the more common carbonaceous chondrites, which deposited a surface layer that we are observing," Cantillo said. This was also observed on asteroid Vesta by the NASA Dawn spacecraft. Asteroid 16 Psyche has been estimated to be worth $10,000 quadrillion (that's $10,000 followed by 15 more zeroes), but the new findings could slightly devalue the iron-rich asteroid. "This is the first paper to set some specific constraints on its surface content. Earlier estimates were a good start, but this refines those numbers a bit more," Cantillo said. The other well-studied asteroid, Bennu, contains a lot of carbonaceous chondrite material and has porosity of over 50%, which is a classic characteristic of a rubble pile. Such high porosity is common for relatively small and low-mass objects such as Bennu—which is only as large as the Empire State Building—because a weak gravitational field prevents the object's rocks and boulders from being packed together too tightly. But for an object the size of 16 Psyche to be so porous is unexpected. "The opportunity to study an exposed core of a planetesimal is extremely rare, which is why they're sending the spacecraft mission there," Cantillo said, "but our work shows that 16 Psyche is a lot more interesting than expected." Past estimates of 16 Psyche's composition were done by analyzing the sunlight reflected off its surface. The pattern of light matched that of other metallic objects. Cantillo and his collaborators instead recreated 16 Psyche's regolith—or loose rocky surface material—by mixing different materials in a lab and analyzing light patterns until they matched telescope observations of the asteroid. There are only a few labs in the world practicing this technique, including the UArizona Lunar and Planetary Laboratory and the Johns Hopkins Applied Physics Laboratory in Maryland, where Cantillo worked while in high school. "I've always been interested in space," said Cantillo, who is also president of the UArizona Astronomy Club. "I knew that astronomy studies would be heavy on computers and observation, but I like to do more hands-on kind of work, so I wanted to connect my studies to geology somehow. I'm majoring geology and minoring in planetary science and math." "David's paper is an example of the cutting-edge research work done by our undergraduate students," said study co-author Vishnu Reddy, an associate professor of planetary sciences who heads up the lab in which Cantillo works. "It is also a fine example of the collaborative effort between undergraduates, graduate students, postdoctoral fellows and staff in my lab." The researchers also believe the carbonaceous material on 16 Psyche's surface is rich in water, so they will next work to merge data from ground-based telescopes and spacecraft missions to other asteroids to help determine the amount of water present. https://phys.org/news/2021-06-asteroid-psyche-scientists.html
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A combined team of researchers from Durham University and Sea Search Research and Conservation NPC, has found that a gray whale spotted off the coast of Namibia traveled halfway around the globe to get there. In their paper published in the journal Biology Letters, the group describes collecting a tissue sample from the whale and comparing its DNA with other whales in other parts of the world. Back in 2013, fishermen reported seeing a gray whale swimming around in Walvis Bay off the coast of Namibia—a very unusual sight since gray whales had not been seen in these waters before. Eventually, the reports made their way to oceanographers and zoologists and a team of researchers was formed to find out more about the whale. A research vessel was sent and the team aboard managed to obtain a small tissue sample from the 40-foot whale. Back in their lab, the researchers conducted a DNA analysis of the sample and then compared it with other whale samples held in biotechnology databases. They found a match—the gray whale swimming in Walvis Bay was directly related to a western population of gray whales that normally live in the North Pacific. Western gray whales are endangered; researchers believe that there are only 200 left in the world. Thus, sightings have been few—most have occurred off the coasts of Alaska and Russia. Once the whale's original home had been found, the researchers began looking at different routes it might have taken to make it to a southwest part of Africa. They found it could have taken a Canadian route through the Northwest Passage. But it also could have swum down and around South America or even across the Indian Ocean. Also unclear is why the whale made such a long journey—whichever route it took would have taken it halfway across the planet, a trip that marks a record travel length for a mammal. The researchers suggest it could have been responding to warming temperatures in its natural home or it could simply have become lost. https://phys.org/news/2021-06-gray-whale-coast-namibia-swam.html
52 views · Jun 9th
A team of researchers from Oklahoma State University, the University of Central Oklahoma and the University of Arkansas has found that the mere sight of sick birds of their own kind is enough to set off an immune response in healthy canaries. In their paper published in the journal Biology Letters, the group describes experiments they conducted with caged birds in their lab. Prior research has shown that many animals, humans included, tend to avoid others of their kind when they show signs of illness. But for some species, doing so might be more problematic than risking getting sick. Birds that rely on safety in numbers, for example, may need another strategy for dealing with ailments. In this new effort, the researchers found that for at least one species of bird, simply seeing others of its kind become sick was enough to kick off an immune response. The experiments by the researchers involved setting groups of cages with canaries in them across from one another and then infecting one of the groups with a mild bacterial infection. Symptoms of the infection become obvious as infected birds become lethargic after developing conjunctivitis. The researchers note that such infections make the birds look very sick. In their experiment, the researchers were careful to place the uninfected birds far enough away from sick birds to keep them from getting infected. They also set up an identical scenario in a distant part of the lab as a control—neither group was infected with the bacteria. The researchers then monitored what happened over the course of a month, collecting blood samples and making notes regarding how sick birds looked and how easily a well bird could see a sick bird. They found that as the infected birds started to look sick, the immune systems of the healthy birds began to stir. CH50 measurements showed a rise in all of the healthy birds and rose even more in those birds who had the best view of the sickest birds. The researchers also found white blood cell counts rose. Notably, cytokine levels did not change. https://phys.org/news/2021-06-canaries-sight-sick-birds-immune.html
55 views · Jun 9th
The coronavirus variant driving India's devastating COVID-19 second wave is the most infectious to emerge so far. Doctors now want to know if it's also more severe. Hearing impairment, severe gastric upsets and blood clots leading to gangrene, symptoms not typically seen in COVID-19 patients, have been linked by doctors in India to the so-called delta variant. In England and Scotland, early evidence suggests the strain — which is also now dominant there — carries a higher risk of hospitalization. Delta, also known as B.1.617.2, has spread to more than 60 countries over the past six months and triggered travel curbs from Australia to the U.S. A spike in infections, fueled by the delta variant, has forced the U.K. to reconsider its plans for reopening later this month, with a local report saying it may be pushed back by two weeks. Higher rates of transmission and a reduction in the effectiveness of vaccines have made understanding the strain's effects especially critical. Comment: Without more data it's unclear what effect the experimental mass vaccination campaign has had on these variants, because in the UK outbreaks are correlated with an increase in vaccinations: Death rate in England is lowest since records began 20 years ago "We need more scientific research to analyze if these newer clinical presentations are linked to B.1.617 or not," said Abdul Ghafur, an infectious disease physician at the Apollo Hospital in Chennai, southern India's largest city. Ghafur said he is seeing more COVID-19 patients with diarrhea now than in the initial wave of the pandemic. 'New enemy' "Last year, we thought we had learned about our new enemy, but it changed," Ghafur said. "This virus has become so, so unpredictable." https://www.sott.net/article/453894-Gangrene-gastric-problems-and-hearing-loss-reported-in-delta-variant-of-coronavirus-from-India-may-carry-higher-risk-of-hospitalization
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A combined team of researchers from Durham University and Sea Search Research and Conservation NPC, has found that a gray whale spotted off the coast of Namibia traveled halfway around the globe to get there. In their paper published in the journal Biology Letters, the group describes collecting a tissue sample from the whale and comparing its DNA with other whales in other parts of the world. Back in 2013, fishermen reported seeing a gray whale swimming around in Walvis Bay off the coast of Namibia—a very unusual sight since gray whales had not been seen in these waters before. Eventually, the reports made their way to oceanographers and zoologists and a team of researchers was formed to find out more about the whale. A research vessel was sent and the team aboard managed to obtain a small tissue sample from the 40-foot whale. Back in their lab, the researchers conducted a DNA analysis of the sample and then compared it with other whale samples held in biotechnology databases. They found a match—the gray whale swimming in Walvis Bay was directly related to a western population of gray whales that normally live in the North Pacific. Western gray whales are endangered; researchers believe that there are only 200 left in the world. Thus, sightings have been few—most have occurred off the coasts of Alaska and Russia. Once the whale's original home had been found, the researchers began looking at different routes it might have taken to make it to a southwest part of Africa. They found it could have taken a Canadian route through the Northwest Passage. But it also could have swum down and around South America or even across the Indian Ocean. Also unclear is why the whale made such a long journey—whichever route it took would have taken it halfway across the planet, a trip that marks a record travel length for a mammal. The researchers suggest it could have been responding to warming temperatures in its natural home or it could simply have become lost. https://phys.org/news/2021-06-gray-whale-coast-namibia-swam.html
52 views · Jun 9th
A team of researchers from Oklahoma State University, the University of Central Oklahoma and the University of Arkansas has found that the mere sight of sick birds of their own kind is enough to set off an immune response in healthy canaries. In their paper published in the journal Biology Letters, the group describes experiments they conducted with caged birds in their lab. Prior research has shown that many animals, humans included, tend to avoid others of their kind when they show signs of illness. But for some species, doing so might be more problematic than risking getting sick. Birds that rely on safety in numbers, for example, may need another strategy for dealing with ailments. In this new effort, the researchers found that for at least one species of bird, simply seeing others of its kind become sick was enough to kick off an immune response. The experiments by the researchers involved setting groups of cages with canaries in them across from one another and then infecting one of the groups with a mild bacterial infection. Symptoms of the infection become obvious as infected birds become lethargic after developing conjunctivitis. The researchers note that such infections make the birds look very sick. In their experiment, the researchers were careful to place the uninfected birds far enough away from sick birds to keep them from getting infected. They also set up an identical scenario in a distant part of the lab as a control—neither group was infected with the bacteria. The researchers then monitored what happened over the course of a month, collecting blood samples and making notes regarding how sick birds looked and how easily a well bird could see a sick bird. They found that as the infected birds started to look sick, the immune systems of the healthy birds began to stir. CH50 measurements showed a rise in all of the healthy birds and rose even more in those birds who had the best view of the sickest birds. The researchers also found white blood cell counts rose. Notably, cytokine levels did not change. https://phys.org/news/2021-06-canaries-sight-sick-birds-immune.html
55 views · Jun 9th
The coronavirus variant driving India's devastating COVID-19 second wave is the most infectious to emerge so far. Doctors now want to know if it's also more severe. Hearing impairment, severe gastric upsets and blood clots leading to gangrene, symptoms not typically seen in COVID-19 patients, have been linked by doctors in India to the so-called delta variant. In England and Scotland, early evidence suggests the strain — which is also now dominant there — carries a higher risk of hospitalization. Delta, also known as B.1.617.2, has spread to more than 60 countries over the past six months and triggered travel curbs from Australia to the U.S. A spike in infections, fueled by the delta variant, has forced the U.K. to reconsider its plans for reopening later this month, with a local report saying it may be pushed back by two weeks. Higher rates of transmission and a reduction in the effectiveness of vaccines have made understanding the strain's effects especially critical. Comment: Without more data it's unclear what effect the experimental mass vaccination campaign has had on these variants, because in the UK outbreaks are correlated with an increase in vaccinations: Death rate in England is lowest since records began 20 years ago "We need more scientific research to analyze if these newer clinical presentations are linked to B.1.617 or not," said Abdul Ghafur, an infectious disease physician at the Apollo Hospital in Chennai, southern India's largest city. Ghafur said he is seeing more COVID-19 patients with diarrhea now than in the initial wave of the pandemic. 'New enemy' "Last year, we thought we had learned about our new enemy, but it changed," Ghafur said. "This virus has become so, so unpredictable." https://www.sott.net/article/453894-Gangrene-gastric-problems-and-hearing-loss-reported-in-delta-variant-of-coronavirus-from-India-may-carry-higher-risk-of-hospitalization
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