Even really old stars have Earth-like planets
June 30, 2015
Brett Smith for redOrbit.com – @ParkstBrett
If there is another civilization out there in the universe like our own, it may have had a couple billion years head start on us.
According to a new study published in Monthly Notices of the Royal Astronomical Society, several distant stars with Earth-like planets are around 11 billion years old – that’s about 6.5 billion years older that the Sun.
The study is based on an examination of 33 stars with Earth-like planets identified by NASA’s Kepler satellite. For each star, researchers were able to determine age, density, diameter, mass, and distance from Earth with more precision than ever.
“Our team has determined ages for individual host stars before with similar levels of accuracy, but this constitutes the best characterized set of exoplanet host stars currently available,” study author Victor Silva Aguirre, from the Stellar Astrophysics Centre at Aarhus University in Denmark, said via press release.
Measuring like an earthquake
Stars examined in the study are actually solar-like oscillators that send out waves like the sound waves emanating from a stereo or musical instrument.
“The term solar-like oscillators means that the stars exhibit pulsations excited by the same mechanism as in the Sun: gas bubbles moving up and down,” Silva Aguirre said. “These bubbles produce sound waves that travel across the interior of stars, bouncing back and forth between the deep interior and the surface producing tiny variations in the stellar brightness.”
Study researchers were able to pick up these vibrations through asteroseismology – a technique similar to the one geologists use to map out the structure of the Earth’s interior during earthquakes. By inputting data of oscillation frequencies and average asteroseismic parameters, the researchers were able to parse information about each star with unprecedented accuracy.
While the study incorporated just a small section of the sky near the constellation Cygnus, the research team said it’s reasonable to conclude there are countless stars older than our Sun with Earth-like planets in the universe.
“One of the biggest questions in astrophysics is: does life exists beyond earth? To even begin answering this, we need to know how many planets like ours exist out there, and when they formed,” Silva Aguirre said. “The stars we studied harbor exoplanets of size comparable to earth, and our results reveal a wide range of ages for these host stars, both younger, as low as half the Sun’s age, and up to 2.5 times the age of the Sun.”
on: Today at 05:21 AM
|Started by Rad - Last post by Rad|
on: Today at 05:19 AM
|Started by Rad - Last post by Rad|
Tiny black holes power brilliant phenomena
June 30, 2015
Brett Smith for redOrbit.com – @ParkstBrett
Ultra-luminous X-ray sources (ULXs) are mysterious objects that emit brilliant light and about million times more powerful than the Sun.
A new study published in Nature Physics revealed a major detail about these strange phenomena: They are powered by “tiny monster” black holes with masses only about 100 times that of the Sun. (Seems pretty big to us.)
ULXs stream powerful and amazing outflows of material that are created as matter drops onto their black holes at a blindingly high pace. Scientists weren’t sure if these outflows were created by an extremely massive black hole, or a small veracious one. In addition to finding that they were powered by relatively small black holes, the study found these objects appear to be related to of SS 433, one of the most exotic items in our own Milky Way Galaxy.
The team said their findings also inform our knowledge of how supermassive black holes in galactic centers are created and just how matter rapidly drops onto those black holes.
At its most basic level, a ULX is a close binary system made of a black hole and a star. As material from the star drops onto the black hole, an accretion disk develops around it. As the gravitational energy of the matter is released, the deepest part of the disk is heated to a temperature greater than 10 million degrees, which causes it to give off strong X-rays.
In the study, researchers observed four ULX objects: Holmberg II X-1, Holmberg IX X-1, NGC 4559 X-7, and NGC 5204 X-1. Using the Subaru Telescope in Hawaii for four nights, researchers from Japan and Russia captured high-quality spectra data.
The width of a spectral line indicates the velocity dispersion of its gas and in each ULX, the study team discovered a broad emission line from helium ions. The velocity dispersion indicating it was heated to several tens of thousands of degrees in the system. Researchers also found that the width of the hydrogen line is greater than the helium line. Together, these findings indicate the gas must be speeding outward as a wind from the accretion disk or the companion star cools it down while it escapes.
The “supercritical accretion” seen from these tiny black holes is thought to be a possible way in which supermassive black holes form at galactic centers in a relatively short period of time, the researchers said.
Study author Yoshihiro Ueda, an astrophysicist at Kyoto University in Japan, noted in a press release there are still a number of unanswered questions regarding ULXs.
“We would like to tackle these unresolved problems by using the new X-ray observations by ASTRO-H, planned to be launched early next year, and by more sensitive future X-ray satellites, together with multi-wavelength observations of ULXs and SS 433,” he said.
on: Today at 05:17 AM
|Started by Rad - Last post by Rad|
Meet Geophilus hadesi: The centipede from hell
June 30, 2015
Chuck Bednar for redOrbit.com – @BednarChuck
Scientists have found a new type of centipede that is the deepest underground dwelling creature of its kind – a species that has been found as deep as 1100 meters below the Earth’s surface and was named Geophilus hadesi after Hades himself.
In research published today in the journal ZooKeys, Dr. Pavel Stoev, a zoologist at the National Museum of Natural History, Sofia, and his colleagues explained that the Hades centipede was also named to pair with an underground-dwelling relative named after Persephone, the queen of the underworld. They are the only geophilomorphs to have adapted to live exclusively in caves, the researchers explained. Most typically only find shelter there sporadically.
“The species was discovered in three deep, hardly accessible vertical caves located in the Velebit Mountains in Central Croatia. It lives at a great depth, in complete darkness and high humidity, often in large spacious places and close to water,” Dr. Stoev told redOrbit via email. It was found by study co-author Ana Komerički and a team from the Croatian Biospeleological Society.
New centipede has unique antennae, poisonous fangs
Dr. Stoev explained that the discovery is unique in that, while there are between 1000 and 1250 extant species that comprise the centipede order Geophilomorpha, this is just the second species in the genus to display what he calls “troglomorphic traits,” meaning its entire life-cycle takes place in caves.
Furthemore, he told redOrbit that among the few troglobites in the order, Geophilus hadesi has “exceptionally elongated antennae, trunk segments, and leg claws, which speaks of a long (most likely in the course of millions of years) evolution in caves. It was recorded at a depth of minus 1100 m, which represents the world’s deepest record of a centipedes as a whole.”
The creature also reportedly has a powerful jaw containing poison glands, and as it uses its claws to capture and tightly hold its prey, the Hades centipede is one of the top predatory creatures currently living in the Velebit caves. Dr. Stoev estimates that, even with this new discovery, we may have only found half the world’s centipede species.
“There are currently approximately 3300 described species of centipedes, but still a large proportion of the existing centipede diversity remains unknown,” he told redOrbit. “It is estimated that the actual number of the species that occur on our planet is between 6000 and 10,000, which means that centipede researchers have still a lot to do.”
Dr. Stoev added that while, like all centipedes, the new species has “poisonous fangs that are used for grasping the prey. Centipedes mostly feed on invertebrates… but the centipede venom can affect also vertebrates,” he said. While there are “a few documented cases of centipede bites” that have been lethal to people, the new species “is likely to be harmless to humans.”
on: Jun 30, 2015, 09:35 AM
|Started by Gonzalo - Last post by Gonzalo|
Here I'm posting a simple diagram of the CARE/nurturance system as described by Panksepp, with relevant EA correlations with the anatomical areas and brain chemicals.
In Panksepp’s affective neuroscience this is the brain system that activates maternal behavior and also more generally parental behavior because in varying degrees males are involved in parenting in different species. This system involves brain circuitry and neurotransmitters that are triggered by environmental inner or outer stimuli, that then induce or promote various aspects of maternal caring/nurturant behavior. The description of these systems by Panksepp is focused in determining the brain areas/circuits which are necessary for the adaptive behaviors to manifest, while there generally exist other brain areas which are also involved in the complex sets of behaviors. As relates to the CARE/nurturance, neurochemical systems are found within the subcortical reaches of the visceral nervous system, including areas like the cingulate cortex, septal area, bed nucleus of the stria terminalis, and preoptic and medial areas of the hypothalamus, together with their mesencephalic projection areas. Brain oxytocin, opioids, and prolactin systems are key actors in eliciting maternal behavior, and, further, “subtle feelings that we humans call acceptance, nurturance, and love”. Components of this CARE system such as the role of oxytocin are fundamental along the whole process of reproduction, gestation, birth, breastfeeding, and in promoting the emotional states adequate for child rearing, and the natural socialization process required for this. “In mammals, the ancient molecules that control reptilian sexuality and egg laying evolved into the oxytocin and arginine-vasopressin (AVP) social circuits of the brain”. When parturition nears, levels of estrogen increase rapidly, while progesterone rapidly diminishes. Prolactin rises inducing the production of milk. Hormonal changes prepare the mother to manifest maternal urges before the moment of birth, such as house preparation, nest building, and an increased eagerness to interact with ‘baby rats’. These behavior tend to be clearer when the mother has given birth before. If such pattern of hormonal changes is created by injections, virgin rats can also manifest maternal behavior. Within this, the role of oxytocin is prevalent. During the last days of pregnancy and the first few days of lactation, there are remarkable increases in oxytocin receptors in several brain areas, and in the number of hypothalamic neurons that begin to produce the oxytocin. During lactation, oxytocin cells develop ‘gap junctions’ between adjacent oxytocinergic neurons, which helps suckling from nursing babies to more effectively trigger oxytocin secretion in the brain of the mother, serving to sustain a maternal mood, and release from the pituitary gland for milk to be released from the breasts. The greatest oxytocin receptor proliferation within the brain takes place in the bed nucleus of the stria terminalis (BNST). Brain circuits controlling various components of the full display of maternal behavior extend far and wide in subcortical regions of the brain. Part of the circuitry descends from the preoptic area along a dorsal route through the habenula to the brain stem, and part through a hypothalamic route to ventral tegmental area (VTA) dopamine systems and beyond. “The VTA component may facilitate general foraging tendencies that are essential in retrieval and nest building, while the other routes may be more important in up-close nurturance and nursing.”
In turn, emotional states arise in the child’s brain connected to security, protection, and love, through the dyadic regulation and synchronization of behavior with the mother or caregivers, by means of the initial instinctive mutual responses of both, that then gradually develop into socialized behavior. As an example, “newborn birds of species that are born relatively mature (i.e., precocious species such as chicks, ducks, and geese) will typically learn to follow the first moving object they encounter.” In mammals, oxytocin and opioids are fundamentally involved in the emotional states and circuitry that are activated in the baby by loving caregiving, and which will not work properly-with many potential manifestations-when such loving conditions do not exist. A typical manifestation in many mammalian species is what are called separation distress vocalizations (DV), which are adaptively selected behavior serving to attract caregiver’s attention, once the PANIC/separation distress system has become active. Oxytocin has been demonstrated to inhibit separation calls in various species, affirming that this type of social comfort is produced by the same brain chemistries that help mediate maternal (and sexual) behaviors.
If anyone wishes to comment, or ask, please go ahead.
God Bless, Gonzalo
on: Jun 30, 2015, 09:27 AM
|Started by Rad - Last post by Rad|
What your brain looks like after a near-death experience
June 29, 2015
On August 24, 2001, Air Transat Flight 236, with 306 passengers and crew members aboard, began its scheduled flight from Toronto to Lisbon, Portugal, but didn’t quite make it. Midway over the Atlantic Ocean, there was a fuel leak, then a power outage, and Captain Robert Piché and First Officer Dirk de Jager decided to make an emergency landing. The lights went off, the engines failed, cabin depressurization began, and passengers were given instructions for the deployment of life jackets and oxygen masks.
But just after announcing the plane was about to go into the water, Piché spotted a runway in the Azores, the volcanic islands about 900 miles off the coast of Portugal. To lose altitude, he conducted one 360-degree turn and additional S-turns. Passengers screamed as the plane swung around, then back and forth, but outside their windows they saw water turn to land. Warning his passengers to brace themselves, Piché then aimed for the landing strip, and the plane hit it twice before the crew could apply maximum braking pressure and bring the 200-ton aircraft to a stop. Miraculously, nobody died.
In the years since, the survivors of that near-death experience have become a sort of lab experiment for researchers trying to understand the long-term consequences of post-traumatic stress disorder (PTSD). The person who proposed studying these survivors was Dr. Margaret McKinnon, an associate professor of psychiatry and neuroscience at McMaster University in Ontario, Canada, and one of the passengers on Flight 236. She developed PTSD after that harrowing landing.
“The study was an opportunity to turn something negative into a positive experience and hopefully make a contribution to the science of PTSD,” she says.
In an initial experiment conducted three years after the traumatic incident, 15 passenger-participants—seven with PTSD—completed a memory test to probe the quality of their memories of the flight. “Everyone on board had a different experience,” says McKinnon. Uncomfortable discussing the details of her trauma from that day, she just says, “I thought I would die and came to some form of acceptance around that.”
For the study, participants also were asked to recall two other events: their memories of the events of 9/11 and a neutral autobiographical event. These two other memories would serve as comparison points and help the researchers understand how trauma affects memory.
“There were two main findings from that study,” says Brian Levine a professor of psychology at the University of Toronto and one of the researchers on the project. First, all the passengers remembered a remarkably large amount of detail from the Air Transat incident. Levine refers to this as emotionally enhanced memory. “Everyone on the plane generated two to three times more information about that event than other events we tested,” he says.
The second finding was that the people with PTSD tended to veer off-topic when interviewed about the near-crash, recalling additional but somewhat irrelevant information, compared with the people without PTSD. This suggests they have problems with their control over memory, says Levine. Interestingly, those with PTSD not only remembered more external, tangential details from the traumatic plane landing; their recollections of 9/11 and the neutral event were also cluttered with superfluous details.
Nearly a decade following this initial stage of research, eight passengers agreed to return for a second chapter of the study. This group, which had a brain scan, ranged in age from 30s to 60s and included some who had been diagnosed with PTSD. Placed inside a functional MRI scanner, the eight passengers recalled details of their experience on Flight 236 while they watched the Discovery Channel’s video re-creation of the incident, which included looking down on the island where the emergency landing took place.
“I can tell you, I re-experienced the event, it was that evocative of the experience,” says McKinnon, who participated in the study. “I felt I was suspended in the air again.”
She adds, “They say in trauma the body keeps the score,” and the study’s results provide a neurological explanation why: As the participants recalled their near-plane crash experience, emotional memory regions of their brains lit up—the amygdala, hippocampus and midline frontal and posterior regions.
“Memory is an activation of a number of brain regions at once,” says Daniela Palombo, lead author of the study and a postdoctoral researcher at the Boston University School of Medicine. “The amygdala is classically involved in emotion, while the hippocampus is important to memory. The posterior regions play a role in visual imagery, and the prefrontal cortex comes onboard for self-referential processes.”
Following their latest Flight 236 re-creations, the passengers were asked to recall their experience of 9/11 while watching footage of the terrorist attacks, and, finally, they recalled a neutral autobiographical event. The participants’ brain activity when discussing 9/11 was similar to what had occurred during their memories of the near-plane crash. And, as expected, the pattern did not occur when they recalled a neutral event. What was surprising, though, is that these patterns were not evident in people who hadn't been involved in a near-plane crash, even when they recalled 9/11 while undergoing a brain scan.
“People who have observed trauma might see the world differently,” says Palombo. She believes the emergency landing scare may have changed the way the brains of those passengers process new information. Following trauma, we may be more sensitive to painful life experiences, Palombo suggests, and so we view the world through new lenses. “The research supports the idea of a lasting memory trace, a carryover effect,” she says.
Those passengers would be more affected by 9/11 because, Palombo says, it “hits home—certainly we can imagine they would relate to 9/11 differently than other people.” And PTSD research supports the idea that any element resembling the traumatic event will be perceived by a trauma survivor as threatening, even when it occurs in a safe environment.
The two studies also suggest that how you see the world to begin with may make you more or less predisposed to PTSD, should you undergo a traumatic experience. “Everybody’s memory works differently,” explains Levine. Some people remember events in a precise way, with relevant details lining up in an orderly fashion, while other people seem to take in more superfluous details in a more disorganized way.
“For people who have that second kind of memory, more extraneous information getting in, they may be more susceptible to PTSD when traumatized,” Levine speculates. “It’s the interplay between the cognitive systems and the emotional systems that may determine how you cope.” In those who develop PTSD, “the emotional part may overwhelm the system,” he says.
These findings add fuel to the theory that when it comes to PTSD, it’s not so much that a traumatic memory exists but that it can be later triggered in unpredictable ways and unexpected times. McKinnon’s hope is that an enriched knowledge of brain activity following a traumatic experience could help advance current therapies built around processing these uncontrolled memories.
Discussion / Evolutionary Astrology Q&A / Re: Pluto in Cap, the climate, ecology and environment topic
on: Jun 30, 2015, 07:25 AM
|Started by Steve - Last post by Rad|
Dying Amazon Healers Take Potential Cures For Cancer, AIDS And Other Diseases With Them
SANTA CLARA, Peru — “Every time a shaman dies, it is as though a book is burned,” says Jose Roque mournfully as he hacks through a vine with a machete.
The 63-year-old indigenous Shipibo healer is showing me around an overgrown jungle garden behind the traditional thatched-roof hut he calls home here in the heart of the Peruvian Amazon.
Roque has long been cultivating plants on this dense patch of rain forest to treat a host of ills, including headaches, nausea, inflammation, skin rashes and menstrual pains.
Once dismissed as primitive charlatans, medicine men like Roque are increasingly being recognized by scientists for their very real abilities.
Their skills and knowledge, acquired over thousands of generations spent experimenting with Amazonian wildlife, are now viewed as key to unlocking the rain forest’s vast potential to provide new pharmaceuticals — for everything from the common cold to cancer and AIDS.
Already five of the top 10 prescription medicines in the United States are derived from living organisms. For cancer drugs, the proportion is even higher, with three-quarters coming from biological sources.
And nowhere is richer in animal and plant species than the Amazon, the most biodiverse ecosystem on Earth.
Yet testing plants for potential treatments is a long and costly business. Only one of every 10,000 to 20,000 natural compounds screened by scientists ever becomes a drug approved by the US Food and Drug Administration.
That’s where native peoples come in, with their huge head start over Western medicine on identifying the jungle’s active compounds.
But younger generations here are increasingly rejecting their ancestral roots for a Western lifestyle. That means scientists are losing the shortcut of indigenous knowledge to finding the most promising natural substances in the world’s largest tropical rain forest.
During the 20th century, 90 tribes are thought to have disappeared across the Amazon, an area two-thirds the size of the contiguous United States. Some were wiped out by Western diseases to which they had no immunity. Others vanished as their members abandoned their traditional culture just to survive in the white man’s world.
In the last 15 years, the pace has accelerated as roads, logging, agriculture, mining and damming increasingly penetrate the jungle, says Michael Harner, a US anthropologist who has been studying Amazonian shamanism for more than 50 years.
“I am pessimistic. It is a very serious situation,” adds Harner, who founded the San Francisco-based Foundation for Shamanic Studies.
Protecting the Amazon jungle will not be enough. Culture must be maintained, too. This study of a Colombian tribe, led by a University of California, San Francisco expert, noted how their “healing tradition is a complex art of diagnosis, examination, communication, ritual and treatment, which cannot be ‘saved’” simply by preserving plants.
No one seems to know for sure how many medicine men still survive across the Amazon. But the scale of their natural cabinet is staggering. Just in the northwestern Amazon, locals use 1,300 different plants medicinally.
Indigenous village of Santa Clara.
Mark Plotkin, a Harvard and Yale-trained ethnobotanist who’s spent three decades studying Amazonian medicine, is dismissive of claims that shamanism, the healing practices of native peoples, is just mumbo-jumbo witchcraft — or that Western science has all the answers.
“Amazonian natives have been using this stuff for thousands of years. Of course, they have observed whether it works,” says Plotkin, who leads the Amazon Conservation Team, a US nonprofit dedicated to preserving indigenous knowledge.
“The mistake that some people make is thinking that Indians know everything. Clearly, that is nonsense. But thinking that they know nothing is also rubbish. Western medicine is also full of holes. Where’s the cure for pancreatic cancer or acid reflux?”
Plotkin also skewers the accusation that native medicine, unlike its modern, scientific counterpart, is based on rituals and placebos.
“When you walk into a pharmacy in Lima, London or New York, the pharmacist wears a white coat. Why?” asks Plotkin rhetorically. “High street pharmacists haven’t been mixing medicines for a century now.”
Yet in the Amazon, indigenous healers, and their entire way of life, are simply unable to compete with modernity.
“It is very severe what is happening to our people,” says Roque. “When the young don’t learn and the old die, the myths die too. The few elderly people who still know our songs don’t dare sing them because they get laughed at.”
For Roque’s children and grandchildren, temptations to break with tradition are all around. They live in Santa Clara, on the outskirts of Pucallpa, one of Peru’s fastest growing cities. Their village was founded in the 1970s by missionaries who encouraged the Shipibos to give up their nomadic lifestyle and settle there.
Fueled by illegal logging, Pucallpa is high-decibel, chaotic and vibrant. The city is packed with discos, bars, fast food joints and street markets full of cheap, Chinese-produced clothing and blaring salsa music. Two huge, gleaming malls have been built in the last 10 years, as Western consumer culture takes this rain forest frontier by storm.
No wonder towns like Pucallpa across the Amazon draw native youngsters from the surrounding rain forest.
More from GlobalPost: Ayahuasca, an Amazonian trip: http://www.globalpost.com/dispatch/news/regions/americas/111230/ayahuasca-amazon-drug-trip
Even Roque’s nephew Anibal Vazquez — who is enthusiastically learning shamanism, and proud to speak the Shipibo language in front of outsiders — seems torn.
Vazquez, 23, explains how his Chinese motor scooter is on its last legs, but he has no way of scraping together the 800 sols ($260) to buy another.
“The city’s full of pollution, corruption, robbery,” Vazquez says, as he tinkers with the engine. “If you don’t have money, you are lost. But here, you can go to the river to fish, or sow bananas. You are free here.”
Yet Vazquez notes how in the local forest, over-exploited by Pucallpa’s burgeoning population, his community can no longer find the palms they use to thatch their roofs, or the right kind of tree to make dug-out canoes.
There are alternatives, like corrugated metal or fiberglass hulls. But they cost money, which those living a traditional indigenous lifestyle simply don’t have.
Even for Amazonian Indians like Vazquez, who want to maintain their ancient traditions, that bind is propelling them into the cities in search of paid work.
Behind them, they are leaving aging medicine men without the chance to pass on their unique knowledge to the younger generations. “Not a single tribe that has gone extinct in the Amazon had anything written down,” emphasizes Plotkin.
Which is why, as Roque puts it, the loss of each shaman is equal to the destruction of a treasured book.
on: Jun 30, 2015, 07:15 AM
|Started by Rad - Last post by Rad|
Christian Science Monitor
Young crater on Mars hints at Earth-like climate
For the first time, scientists calculate water volumes in a young crater on Mars, revealing Earth-like conditions in the recent past.
By Shontee Pant, Staff writer June 23, 2015
An image by the High Resolution Imaging Science Experiment (HiRISE) camera on the NASA's Mars Reconnaissance Orbiter shows Gullies at the Edge of Hale Crater on Mars recorded during the month of April through early August 2009. (Reuters/NASA/JPL/University of Arizona/Handout)
Mars is a planet of paradoxes, red in color but icy cold. Did its climate ever resemble that of our warm, blue planet? Maybe so, suggests a new study of Istok crater – and not billions of years ago, but in the recent geologic past.
A study led by Tjalling de Haas of Utrecht University has found that the gullies in Istok crater are similar to those on Earth, and could have formed during recent periods of high orbital obliquity.
Istok crater, located in the Aonia Terra region of Mars, has remarkably well-preserved debris-flow tracks, or gullies. These are the first tracks imaged clearly enough to allow scientists to calculate the amount and frequency of water that flowed through them. As he told the Monitor, this is "really something new!"
Debris flows, such as mudslides and avalanches, differ from pure-water flows in that they contain about only 20-60 percent water, located in the tiny gaps between the rocks and dirt.
Once the scientists had calculated the amount of water necessary to create the gullies they observed, they could estimate the amount of snowfall necessary to generate that much water.
Previous research concluded that these tracks could have been carved with just millimeters of water, but Dr. de Haas disagrees. His team calculated that inches or even feet of snow had to pile up at the heads of these valleys in order to explain the debris flow patterns visible in the images taken from orbit.
The Martian climate is currently quite dissimilar from Earth's climate, with very cold temperatures and an almost nonexistent atmosphere. Most of the known water on the planet is frozen at the poles or hidden in deep underground springs. But finding debris flow tracks in a crater that is less than a million years old – their best estimate dates the crater impact to about 190,000 years ago – demonstrates that temperatures were warm enough in the recent past to allow ice to melt, at least in that region.
How could that happen? De Haas theorizes that these Earth-like debris flows occurred at times of high orbital obliquity, because when Mars's axis is tilted more dramatically, it can have much hotter summers (and colder winters) than the present.
While Earth’s axis has remained relatively constant over its history, only shifting between 22.1 to 24.5 degrees (thanks to stabilization from our large moon), Mars has bobbled like a top over tens of millions of years, moving between an almost vertical axis down to an axial tilt of more than 60 degrees. Its axis is currently tilted 25 degrees, but during high obliquity intervals, Mars is lying down almost sideways with respect to its orbit, like Uranus does.
It's still uncertain exactly how much these dramatic changes in axial tilt affect Martian climate, but for comparison, a one degree change in Earth's axis may have ended the ice age, melting glaciers from New York City to Greenland. It's not unreasonable to conclude that massive axial swings on Mars could lead to greater climate variation, creating conditions where snow and ice can first accumulate and then melt, causing debris flows.
This study, published in the current issue of Nature Communications, contributes to the emerging understanding of the dynamic climatic history of the red planet; if these results are replicated in other areas around the planet, it may turn out that Mars was once much more habitable than it currently is.
However, de Haas cautions that his team identified only “a local occurrence, and only during very short periods at high orbital obliquity.” More research is necessary, he adds, to determine whether these conditions were present elsewhere or whether they only speak to an isolated, transient incidence of climate conditions like those on Earth.
The Christian Science Monitor
Mars was not only habitable, it was downright Earth-like, Curiosity finds
Mars' Gale Crater had a long, thin lake that could have supported microbial life in a setting 'really similar to an Earth environment,' according to data collected by NASA's Curiosity rover.
By Pete Spotts, Staff writer December 9, 2013
This file image shows a self-portrait of the Mars rover, Curiosity. Curiosity has uncovered signs of an ancient freshwater lake on Mars that may have teemed with microbes for tens of millions of years, far longer than scientists had imagined, new research suggests. (JPL-Caltech/MSSS/NASA/Reuters/FIle)
NASA's Mars rover Curiosity has uncovered mineral and chemical leftovers in the rocks of Gale Crater that paint a remarkable picture of a modest lake whose mucky bed could have supported microbial life as early as 3.6 billion years ago.
In the process, the rover has laid bare the challenges and opportunities the rover's science team faces as it moves into the second phase of the mission: hunting for organic compounds that would enhance the crater's cosmic credibility as a once-habitable spot beyond Earth.
The lessons learned exploring a formation known as Yellowknife Bay suggest that well-preserved organics – easily destroyed by prolonged long exposure to radiation – may exist within reach of Curiosity's drill if the rover's handlers can find the right spot.
That is encouraging news for a mission that, seven months after it landed, answered "yes" to the question of whether its landing site could once have been habitable. The results released on Monday at the fall meeting of the American Geophysical Union in San Francisco add richness to the story.
The lakes, streams, and groundwater systems the team says were once in Gale Crater “are really similar to an Earth environment,” said John Grotzinger, a geologist at the California Institute of Technology in Pasadena and the project scientist for the mission, at the briefing.
The lake, nestled against the base of Mt. Sharp, the crater's central peak, would have been similar in size to those in the Finger Lakes region of upstate New York – perhaps 30 miles long by 3 miles wide. The climate likely would have been cold and arid, with water supplied by snow in the mountains that form Gale crater's rim.
The rocks the team explored span “millions to even tens of millions of years of time, which is quite a long window of habitability,” Dr. Grotzinger said. He and four colleagues summarized the results in six research papers appearing Friday in the journal Science.
Last March, after drilling into a rock named John Klein, the team announced that the site had been habitable. The site yielded evidence of flowing water. Chemical analysis of the rock sample revealed several of the basic chemical elements important for organic life.
Indeed, the team's interpretation of the data led the scientists to conclude that they had a system of environments that involved not just a lake, but the rivers that fed it and the groundwater deposits that would have developed there.
But there was still some uncertainty about whether the minerals analyzed formed locally, and so pointed to past habitats in the crater, or formed elsewhere and were transported and deposited, suggesting that perhaps the crater might not have had a complete package of traits for habitability.
Team members cleared that up in the new reports, which include analysis of a sample from a mudstone rock dubbed Cumberland. Unlike samples of Martian soil analyzed elsewhere, the clay Cumberland contained was heavy on magnetite and light on olivine, suggesting the clay formed from a local mineral mix, says Douglas Ming, a soil chemist at NASA's Johnson Space Center in Houston and the lead author of one of the six papers in Science.
Moreover, Cumberland's particular blend forms “in pretty benign conditions,” he says – fairly cold temperatures in waters that weren't too acidic or too basic.
Those are conditions “that are pretty unique, that microbes might have survived in,” he says.
on: Jun 30, 2015, 07:07 AM
|Started by Rad - Last post by Rad|
Dramas great and small
Claxton, Norfolk These deer of such sweet mien momentarily suggested nothing less than something sabre-toothed and predatory
Tuesday 30 June 2015 05.29 BST
Through the hedge on the path to the marsh I could hear their commotion. Sharp-tipped hooves stabbing the ground and then a telltale blur of orange flanks that revealed them as Chinese water deer. Males squared up in combat.
As my binoculars dialled into crisp detail, they answered a long-standing mystery. For years I’ve found handfuls of loose deer hair strewn on the ground, but was always puzzled why it was shed in that fashion. Here was the answer.
The males possess long canines in the upper jaw that slot either side of the closed mouth like fangs. Each buck, facing his opponent, feinted and jinked for the opening to land its charge, until one would finally dash at the other.
The rushes were ferocious. The assailant often performed full somersaults over its rival, rolling back upon back, legs flailing down in an instant search for new purchase. And once it landed, the deer would curve around the head of its enemy, gouging its teeth into the other’s flank. Fur flew.
One finally yielded, but not before they had rested in unison, slack mouths wide open, hard-breathed, red-gummed, and those fangs of these deer of such sweet mien momentarily suggested nothing less than something sabre-toothed and predatory.
It had all unfolded to the iambic heart-pounded rhythm of sex, but the next day at Blackwater I encountered a drama whose denouement was but 2cm across, yet it contained a poetry that was darker, harder and more fertile.
We were looking for spiders when one of us came upon a dead dung fly with its legs hugged entirely round a blade of grass. Bizarrely, the abdomen curved back and up, but the head was forward and down as if a fly were bowing in abject submission.
Its whole body glistened with something like sugar frosting, the spores of mould called Entomophthora. Over seven days, it consumes the fly within, and then by some biochemical trick, fashioned through the millennia, it persuades the fly brain to die in an attitude best suited to the dispersal of its spores.
on: Jun 30, 2015, 06:11 AM
|Started by Rad - Last post by Rad|
The Christian Science Monitor
Star of Bethlehem? Jupiter and Venus converge in night sky
On June 30, Jupiter and Venus will converge and create a dramatic 'star' in the Western sky after sunset.
By Beatrice Gitau June 27, 2015
Jupiter and Venus are set to converge in an epic sky event. (NASA)
Jupiter and Venus will merge into a dazzling "super-star" in the Western horizon by the end of June, NASA says.
The conjunction of the two planets has been building during the month of June and will culminate in a spectacular display on June 30. “Every night in June, the separation between Venus and Jupiter will visibly shrink,” says NASA.
A conjunction is when two or more objects appear very close together on the sky.
On the evening of June 30, Venus and Jupiter will appear in the sky just a third of a degree apart. “That's less than the diameter of a full Moon. You'll be able to hide the pair not just behind the palm of your outstretched hand, but behind your little pinky finger,” NASA enthuses.
Sky & Telescope suggests that a similar rare conjunction of Venus and Jupiter may have been what's been called the "Star of Bethlehem" in 3-2 BC.
While the conjunction is certainly visible with the naked eye, Sky and Telescope says viewing it with a telescope or binoculars will offer a different perspective: “Both planets will crowd into same telescopic field of view, Venus appearing as a fat crescent and round Jupiter accompanied by its four large moons. The two planets will appear nearly as the same size, but Jupiter, though much larger in reality, is much farther away.... Their globes will contrast dramatically in brightness, with Venus’s crescent appearing dazzling white compared to Jupiter’s duller, striped cloud deck.”
Pat Hartigan, an astronomer at Rice University, says the conjunction on June 30 is the best one we will have for over a decade, rivaled only by one on March 1, 2023, which will not be not quite as close.
So where and when should we look for it? Look to the west-northwest as soon as it gets dark, says Dr. Hartigan. "After about two hours for most latitudes the objects will become difficult to observe as they begin to set. They are bright. You might mistake them for airplanes."
Is this a significant astronomical event? Not really. "These planetary groupings in the sky have no effect on Earth or human affairs – except for one," says Alan MacRobert at Sky & Telescope. "They can lift our attention away from our own little world into the enormous things beyond. That's what amateur astronomers do all the time."
[Editor's note: The original story incorrectly indicated when the last, close convergence of Jupiter and Venus occurred.]
on: Jun 30, 2015, 06:08 AM
|Started by Rad - Last post by Rad|
Mars pyramid: Alien structure or everyday pareidolia?
NASA says it has spotted a pyramid on Mars. Did an advanced civilization once exist on Mars, or is the brain seeing patterns where there are none?
By Beatrice Gitau, Staff writer June 25, 2015
Christian Science Monitor
Are there pyramids on Mars? Or is it just one pyramid-shaped rock?
On May 7, NASA's Mars Curiosity rover took a snapshot of an atypical stone on the Red Planet.
A raw image from the mission shows a rock that appears to be pyramid-shaped, leading some to speculate that it may be the result of intelligent sculptors. NASA, for its part, says it's just an ordinary rock.
Jim Bell, a member of NASA's Mars Rover Explanation Team told Indianapolis's WISH TV that the object was unlikely to be man- or alien-made, adding that rock formations which look like recognizable objects are very common.
But that hasn't stopped people from speculating about its origin or design. "I would theorize that the [artifact] is either the capstone of a much larger pyramid, possibly buried deep beneath the surface, or perhaps a marker stone," says a robotic narrator in a YouTube video uploaded by a user called Paranormal Crucible.
Writing for the website Exopolitics.org, Dr. Michael Salla speculates that NASA deliberately took pains to prevent showing other views of the object to the public in subsequent photos.
Or is it just a rock, as NASA says?
Perhaps interpretations of the object as a man-made structure are driven by our own expectations. A well-known psychological phenomenon known as pareidolia can cause people to interpret random images as significant or meaningful.
A series of reports published by Japanese palaeontologist Chonosuke Okamura in the 1970s and '80s demonstrate the dangers of interpretations resulting from pareidolia. Mr. Okamura described finding ancient fossils of dogs, fish, birds and men, all at tiny sizes, leading him to conclude that modern body shapes existed in ancient times, but at 1/350th scale. Okamura was awarded the 1996 Ig Nobel Prize for his research.
American astronomer and author Carl Sagan argues that pareidolia evolved as a survival tool that allowed humans to recognize faces from a distance or in the dark. The instinct was vital to identifying friend or foe, but Dr. Sagan noted that it could cause people to misinterpret patterns.
And don't underestimate the power of expectations, says Sophie Scott, professor of neuroscience at the University College London. "Being able to see Jesus's face in toast is telling you more about what's happening with your expectations, and how you're interpreting the world based on your expectations, rather than anything that's necessarily in the toast," Dr. Scott told the BBC.
In other words, seeing a pyramid on Mars, instead of just a funny-shaped rock, could tell us more about our expectations of life in Mars than anything about actual Martian history.