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 on: Oct 22, 2016, 05:29 AM 
Started by Rad - Last post by Rad
CS Monitor

Did the Viking rover actually discover signs of life on Mars in 1976?

In 1976, NASA sent two probes, Viking 1 and Viking 2, to the Red Planet to test for signs of life. Two of the scientists now argue that their experiments' results should be reexamined in light of more recent tests.

By Story Hinckley, Staff October 21, 2016

In a study published earlier this month in the journal Astrobiology, two researchers say the scientific community should take a closer look at a study of Mars’ soil published in 1976.


Because two NASA robots may have discovered signs of life on Mars almost four decades ago, say Gilbert Levin from Arizona State University and Patricia Ann Straat from the US National Institutes of Health.
Recommended: Man and Mars through history

It all started when NASA sent two probes, named Viking 1 and Viking 2, to Mars in 1976 to test for signs of life on the Red Planet. As the first spacecraft from Earth to reach Mars, the Viking probes conducted three studies on the planet’s biology.

To conduct one of the studies, the labed release (LR) experiment, scientists took soil picked up by the Viking probes and mixed it with nutrient-rich water. If the soil had signs of life, the scientists hypothesized, then the soil’s microbes would metabolize the nutrients in the water. Scientists conducted the experiment across a variety of Earth’s soils, from Death Valley to Antarctica, to disprove the potential for false positives.

And to the scientists’ surprise, the microbes were metabolized and radioactive molecules were released – suggesting that Mars’ soil contained life.

However, the Viking probes’ other two experiments found no signs of life. Specifically, the Viking probes found no trace of organic material, which made the scientists ask: If there were no organic materials, what could be doing the metabolizing? 

Thus, NASA concluded that some non-biological processes must be responsible for the metabolization.

But Dr. Levin and Dr. Straat say the LR experiment needs to be reexamined in light of more recent evidence, arguing that it is possible that biological processes were responsible for the LR experiment’s results, after all.

"Many believe that the martian environment is inimical to life and the LR responses were nonbiological, attributed to an as-yet-unidentified oxidant (or oxidants) in the martian soil," the authors write in their study. They conclude "that extant life is a strong possibility, that abiotic interpretations of the LR data are not conclusive, and that, even setting our conclusion aside, biology should still be considered as an explanation for the LR experiment."

In other words, the Viking probes didn't necessarily find evidence of life on the Red Planet in 1976 – but the possibility of such a claim needs to be left on the table, they say.

And all of NASA's finding on Mars since the 1976 experiment, such as water and methane, supports the biological hypothesis even further, argue Levin and Straat.

"Even if one is not convinced that the Viking LR results give strong evidence for life on Mars, this paper clearly shows that the possibility must be considered," Dr. Chris McKay, a senior editor of Astrobiology and an astrobiologist with NASA, tells Science Daily. "We cannot rule out the biological explanation. This has implications for plans for sample return from Mars and for future human missions."

 on: Oct 22, 2016, 05:27 AM 
Started by Rad - Last post by Rad
Mars lander falls silent: Has it been lost?

Despite a less-than-ideal fate for the Schiaparelli lander, scientists at the European Space Agency are feeling positive: Space travel is supposed to be tricky, they say.

By Story Hinckley, Staff October 22, 2016

Scientists at the European Space Agency (ESA) are using Thursday’s possibly failed landing on Mars as a learning experience.

The Schiaparelli Mars lander, named for the Italian astronomer who made the first maps of Mars in the 19th century, had a considerable job to do. The 1,272-pound vehicle had to travel more than 300,000,000 miles across the solar system, reaching Mars’ thin atmosphere at 13,000 miles per hour, and then slow down enough as it passed through atmospheric drag to deploy a parachute, landing softly on the planet’s surface.

And all of this went according to plan, until the parachute was released more than half a mile above the Red Planet’s surface. The lander’s signal went quiet 50 seconds before landing, leaving ESA scientists to wonder if the probe crash-landed.

If the Schiaparelli probe had landed successfully on Mars, it would mark a first for Europe, which has never landed a probe on the Red Planet. The United States, however, recently celebrated the fourth birthday of NASA’s Curiosity after the rover landed on Mars in 2012.

Despite the disappointing ending, scientists are staying positive.

"Yes, I am happy," Jan Woerner, ESA’s Director General, told The Guardian. "The engineers are doing great work, but you still need a bit of luck to succeed."

    ESA David Parker: #Mars exploration is hard but that is why we do it. #ExoMars
    — ESA (@esa) October 20, 2016

"There are a number of things that went right," Jonathan McDowell, from the Harvard-Smithsonian Center for Astrophysics, told Popular Mechanics. "They successfully navigated to the top of the Martian atmosphere, the heat shield separated correctly, the parachute – and supersonic Martian parachutes are a really tricky thing to get right – worked, the separation event of all the different pieces coming off seems to have worked. So they've ticked off three or four of the five or six pieces that are needed to make a successful descent."

However, the ExoMars program, a collaboration between the ESA and Russia’s space agency, had high expectations for the Schiaparelli lander.

Schiaparelli’s landing was planned to set the stage for part two of the ExoMars mission: to land a six-wheeled rover (similar to NASA’s Curiosity) in 2020. Because of the future rover’s $330 million price tag, ExoMars leaders were hoping Schiaparelli’s success would reassure investors.

But Mr. Woerner isn’t worried.

"Schiaparelli's primary role was to test European landing technologies," he said in a press release. "Recording the data during the descent was part of that, and it is important we can learn what happened, in order to prepare for the future."

And for now, scientists will study the data that Schiaparelli was able to submit – equivalent to 400,000 pages of information.

"From the engineering standpoint, it’s what we want from a test, and we have extremely valuable data to work with," added David Parker, ESA’s Director of Human Spaceflight and Robotic Exploration. "We will have an enquiry board to dig deeper into the data and we cannot speculate further at this time."

It's possible the rover may still be located.

"When we put it in the Martian environment, the spacecraft didn’t behave exactly as expected," Andrea Accomazzo, ESA’s spacecraft operations manager told The Guardian. "It might take quite some time before we are able to locate it."

 on: Oct 22, 2016, 05:24 AM 
Started by Rad - Last post by Rad
CS Monitor

How did snakes lose their legs?

Limb loss may seem like a major evolutionary change, but on the genetic level the change might have been subtle.

By Eva Botkin-Kowacki, Staff writer October 22, 2016

Snakes haven't always been obligate stomach slitherers. The animals' ancestors scuttled around on legs, scientists say.

And geneticists now think they know what happened.

Previously, scientists thought the change had something to do with a gene associated with limb growth across vertebrates, but the animals' genomes suggested that gene, called sonic hedgehog, hadn't been deleted. Now, two research teams have independently concluded that portions of the DNA that control the sonic hedgehog (Shh) gene had been deleted.

"The modification of small pieces of DNA can generate big changes," says biologist Francisca Leal, who conducted one of the studies.

So what happened?

Sometime after snakes and lizards diverged from their common ancestor, snakes lost their forelimbs. But tiny hindlimbs remained in the last common ancestor of all living snakes, which scientists suggest lived around 128 million years ago.

While most snakes today have no remnants of those hind legs, pythons, boas, and their relatives retain some related primitive structures. These snakes can have a pelvic girdle, the remnant of a femur and a little claw, called a spur, sticking out.

Pythons briefly develop the beginnings of limbs as embryos, and previous research had suggested the Shh gene had something to do with this flicker of limb growth.

So Ms. Leal, as a PhD candidate in Martin Cohn's lab at the University of Florida, dug into python genomes to see what was turning the gene expression off.

In the genome, short sequences of DNA called enhancers are involved in triggering gene activity. And, because Shh is involved in the development of structures other than limbs, there is a specific enhancer associated with limb development, called the ZRS, Dr. Cohn tells The Christian Science Monitor. "The only job of this short stretch of DNA is to turn on sonic hedgehog in the limb buds," he says.

Leal and Cohn found that pythons do have a ZRS, but sections of it have been deleted. And without those key pieces of the limb-specific enhancer, the proteins that bind to the DNA to kick off limb growth can't latch on.

The pair came to these conclusions, published Thursday in the journal Current Biology, by inserting the limb enhancer DNA into the genetics of a normal mouse. With this extra ZRS marked to highlight when the enhancer triggered activity, the team was able to see that the mice "showed very weak activity of the enhancer in just a few cells at a very early stage, and it's not sustained, just like in pythons," Cohn says.

Meanwhile, in California, another team was independently approaching the same problem from another angle.

Instead of simply adding a python's ZRS to normal mice, a team of researchers led by Axel Visel at the Lawrence Berkeley National Laboratory used the gene editing technology CRISPR to replace this segment of DNA in mice with those from other animals including fish, platypuses, bats, chickens, and five different kinds of snakes.

Dr. Visel and his team saw normal limb development in the mice in all cases except when they had snake ZRS in them.

"Even though the sequence is there ... these mice can no longer form proper limbs," Visel tells the Monitor. And, he adds, "If you take the sequence from the snakes that have the most reduced limbs – the advanced snakes – then essentially these mice look just like mice whose regulatory sequence has been completely deleted."

But with the ZRS from less-advanced snakes like pythons, the mice still produced puny little stubs in place of full limbs. This suggests that the ZRS is still somewhat active in the python, which fits with the minimal structures these snakes and their relatives have retained.

Visel's research was also published Thursday, in the journal Cell.

"It is a marvelous example of evolution being understood in genetic detail," Clifford Tabin, an evolutionary geneticist at Harvard University who was not involved in either study, writes in an email to the Monitor. "This is one of the few cases where we know the exact mutations responsible for dramatic changes in the way evolution has sculpted changes in the body plan of animals."

The ZRS is probably just one piece of the puzzle of limb loss in snakes, says Visel. Many other genes play key roles in limb development, and many of them also have regulatory sequences. "We assume that many of these other sequences probably also have undergone a similar functional degradation," he says, but scientists have yet to identify them.

Cohn agrees that the ZRS is probably only part of the story, particularly because the pythons still show a "pulse" of associated activity and limb development.

Limbs had already been disappearing in snake ancestors by the time pythons and their relatives diverged from other snake lineages, he adds. "Pythons and boas … sort of preserved that state of genome evolution in their lineage," Cohn says, thus providing a "kind of intermediate snapshot of a process that was underway, this degeneration of these gene regulatory elements."

This research isn't just about snakes becoming limbless, Visel says. "All vertebrate species share essentially the same set of genes," he explains. "There are not huge differences."

So scientists have puzzled over why different species look so different.

"There has been this hypothesis that much of what makes animal species different from each other has to do with just how these genes are regulated," Visel says. Finding evidence for that has been a challenge, until these limbless snakes provided an opportunity.

 on: Oct 22, 2016, 05:21 AM 
Started by Rad - Last post by Rad
October 22, 2016

How much time should kids spend on screens?

by Chuck Bednar
Red Orbit

In a world dominated by smartphone games like Pokemon Go and powerful game consoles such as the PlayStation 4 and Xbox One, parents seeking tips on how much screen time they should let their children have were typically met with outdated recommendations.

Now, in an attempt to keep pace with an increasingly technology-dominated world, officials with the American Academy of Pediatrics released an updated set of guidelines during a conference in San Francisco held earlier this week, according to and Los Angeles Times reports.

The new recommendations call for children under the age of 18 months to be permitted no screen time, and all other children under the age of 5 to be allowed a maximum of one hour per day, the media outlets said. Parents of older children are given greater leeway in determining the quantity of screen time that they are allowed, and some media uses do not count against that total.

“Children today are growing up in an era of highly personalized media use experiences,” a panel of AAP-approved experts wrote in guidelines to be published in the journal Pediatrics, according to the Times. “So parents must develop personalized media use plans for their children.”

“Families should proactively think about their children's media use and talk with children about it, because too much media use can mean that children don't have enough time during the day to play, study, talk, or sleep,” study author, Dr. Jenny Radesky, added in a statement. “What's most important is that parents be their child's ‘media mentor.’ That means teaching them how to use it as a tool to create, connect and learn.”

More Skyping, less TV viewing is ideal, recommendations say

The researchers recommended no screen time for very young children because they claim that it can be distracting to infants, potentially leading to sleep problems and a parent-child disconnect, according to They also recommend that breastfeeding mothers not use mobile devices or tablets while doing so, since it could cause the child to feel neglected.

For children between the ages of 2 and 5, the AAP recommends “creative, unplugged playtime” while noting that these youngsters can be introduced to screen time, but no more than one hour per day to begin with. They also suggest choosing shows like Sesame Street instead of cartoons on commercial networks, while giving a big thumbs-up to using technology like Skype to hold conversations with relatives, which they say can promote healthy development at this age.

Things get a little more complicated in children over the age of six. The guidelines state that a healthy child’s typical day should consist of school, doing homework, social contact, sleep and at least one hour of physical activity per day. Whatever time is left can be spent in front of a screen, the recommendations said, but such activities should never replace education, physical fitness or much-needed sleep, and parents should be sure to discuss potential technology-related risks like cyber-bullying and sexting with their sons and daughters.

Interestingly enough, the Times pointed out that fewer children are watching two hours or more of television per day than were doing so two decades ago, but it remains unclear is this is due to moms and dads enforcing recommended limits or because of the increasing availability of other types of screens, such as handheld game systems, smartphones and tablet computers.

The latter seems more likely, as the newspaper reported that smartphone use has risen from 52% of children under the age of 8 in 2011 to 75% for that demographic in 2013. This comes despite a lack of evidence that using educational apps on such devices provides any benefits to youngsters under the age of 2. The guidelines are important, the AAP said, due to the health risks associated with excessive screen time, namely obesity. For that reason, they have lowered the recommended amount of television viewing from 2 hours per day to just 90 minutes.

 on: Oct 22, 2016, 05:19 AM 
Started by Rad - Last post by Rad
October 22, 2016

New long-necked dinosaur species discovered in Australia

by Chuck Bednar
Red Orbit

The discovery of two sets of long-necked dinosaur fossils is shedding new light on how these massive creatures originally made their way to Australia approximately 100 million years ago, according to new research published online this week in the journal Scientific Reports.

Based on the remains, which were found in Queensland, the new species were classified as both sauropods (large plant eaters with long necks and tiny heads) and titanosaurs (making them some of the biggest dinosaurs ever to roam the Earth), BBC News and the Los Angeles Times said.

One of the two creatures, Savannasaurus elliottorum, is a previously undiscovered species that was named after the Elliott family, who discovered its fossils on their property while they were herding sheep. The creature’s skeleton was assembled from 17 pallets worth of bones encased in rock, and according to BBC News, the process took more than a decade to complete.

The other creature, Diamantinasaurus matildae, is the first Australian sauropod for which skull fragments had been discovered, the Times reported. Lead researcher Dr. Stephen Poropot of the Australian Age of Dinosaurs Museum and his colleagues said that the specimen’s discovery has allowed them to learn more about the creature’s skeletal anatomy.

Unique species key to plotting sauropods’ migratory path

Thanks to the discovery of these new fossils, Dr. Poropot’s team was able to determine exactly when and how titanosaurs and other sauropods made their way to Australia. As it turns out, they only arrived approximately 100 million years ago – far later than other dinosaurs arrived there – and they most likely traveled from South America, by land, across Antarctica.

According to National Geographic, the researchers determined that these sauropods place on the family tree “strongly suggests” that they were descended from South American ancestors. If that were true, they would have traveled to their new home by land, and the only path available at the time would have been Antarctica, which thanks to global warming, would have been ice-free.

“By plotting the evolution of these sauropods against changes in the positions of the continents, we’ve possibly been able to constrain when these titanosaurs migrated,” Dr. Poropat explained to Nat Geo. However, he added that more analysis was required to fully understand these dinosaurs and that they now plan to comprehensively describe the specimens and confirm their species.

Savannasaurus has garnered the most interest, partially due to the fact that it is the new species, and partially due to the fact that it is rather unique among sauropods. As the authors explained, it was roughly 20 feet tall and weighed between 15-20 tons, but unlike other sauropods, it had very wide hips that probably gave it more stability. Furthermore, the creature’s bones were extremely thin in parts of its pelvis, and it likely had a sizable belly and complex digestive system.

 on: Oct 22, 2016, 05:16 AM 
Started by Rad - Last post by Rad

Here is the link to what JWG called the Planetary Method Of Chart Interpretation: the house method.,832.0.html

God Bless, Rad

 on: Oct 22, 2016, 01:01 AM 
Started by Rad - Last post by Priya
Thank you, Kristin!
 I was already grateful for the wealth of info on EA techniques here. But after reading your many replies to us I am now feeling a much deeper appreciation and affinity for this board, its dedicated facilitators and awesome members. So much more than astrology here. Truly precious!

 on: Oct 21, 2016, 10:39 AM 
Started by Rad - Last post by dollydaydream
Kristin, thanks for taking the time to spend with us on the MB.  Yes on the house method, signs on cusps and planetary rulers.  No worries on dealing with my comments tomoz.  DDD

 on: Oct 21, 2016, 10:34 AM 
Started by Rad - Last post by Kristin
Hi All,

I am very excited about all of the enthusiasm here, you are all doing great work, and your efforts will lead you into waters of greater realization.

Due to the nature of my busy schedule, Rad will be helping me answer some of these questions tomorrow.

Much more to come,



 on: Oct 21, 2016, 10:30 AM 
Started by Rad - Last post by Kristin
HI DollyDayDream,

I will respond to your analysis in the am, I have a very busy day ahead of me and do want to give it the time is deserves.

I am not sure what you are referring to when you say house method of interpretation?

Are you referring to looking at the signs on the house cusps? And the rulers?
If so, this would apply.

Rad, if you understand what she is asking, please follow up with her on this.

Thanks for your contribution DDD,

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