Water Still Flows On Mars, Scientists Say

Water Still Flows On Mars, Scientists Say

By Amina Khan, Los Angeles Times (TNS)

Where there’s brine, there’s water.

Scientists scouring the Red Planet using NASA’S Mars Reconnaissance Orbiter say they’ve found direct chemical evidence of transient saltwater flowing on the surface today.

Granted, they haven’t caught the liquid in the act — and what they’ve detected looks less like salty water and more like watery salt. But nonetheless, the discovery published by the journal Nature Geoscience helps solve a long-standing Martian mystery and sheds light on the potential for life on our nearest planetary neighbor.

“This is the first time we’ve found flowing water on a planet that’s not ours,” said lead author Lujendra Ojha, a planetary scientist and Ph.D. candidate at Georgia Tech.

Scientists got a tantalizing hint that there could be liquid water on the surface back in 2011, when Alfred McEwen, lead scientist for the Mars Reconnaissance Orbiter’s HiRISE camera, along with Ojha and other colleagues, discovered these strange dark streaks on Martian slopes that seem to grow and fade with the seasons. These “recurring slope lineae,” which can stretch up to a few meters, extend downward when it gets warm and then later shrink and fade, reappearing each Martian year.

“Ever since the discovery in 2011 … a number of us have been incredibly excited by the prospect of liquid water on Mars,” said Bethany Ehlmann, a planetary geologist at Caltech who was not involved in the paper. Nonetheless, she added, “we try to be cautious — it’s a big thing to say there’s liquid water on Mars today.”

Granted, Mars’ atmosphere is cold and thin — which means that any pure water that made it to the surface would either freeze or immediately evaporate, depending on the temperature. But a recent study by scientists using NASA’s Curiosity rover found that water might indeed be able to exist briefly on the surface — provided there were enough salts, such as perchlorates, dissolved in the liquid. These salts would keep the water from freezing or evaporating quite as easily and could actually serve to suck moisture back out of the air.

So could liquid water — very salty, briny water — really explain these strange dark streaks on Martian slopes?

Theoretically, the scientists could look for water by using the orbiter’s Compact Reconnaissance Imaging Spectrometer for Mars, or CRISM. CRISM can look for different chemicals in a given spot on the surface by studying the telltale signature of dark bands they’ve left in the light. The problem is, it’s hard to check the light’s chemical fingerprint at the recurring slope lineae, or RSL, because, according to the study, “few locations exist in which RSL are wide or dense enough to fill even a single CRISM pixel.”

So researchers used a method where they focused on the handful of individual pixels that were mostly filled by the recurring slope lineae. They looked at four different spots with recurring slope lineae and discovered a strong fingerprint for hydrated salts — salts with water locked into the mineral structure, a clear sign that saltwater likely had flowed there. The hydrated salts included magnesium perchlorate, magnesium chlorate and sodium perchlorate.

The findings may further whet the appetite of astrobiologists looking to probe past habitable environments on the Red Planet, researchers said.

“I think it’s incredibly exciting, because when we look back at the broad scope of Mars history, it’s always in the past where there’s evidence for the most water,” Ehlmann said. “But if there’s liquid water even today, when Mars is supposedly at its driest … I think that says that there was probably liquid water for all of the last 4.5 billion years, just like there was on Earth. Not in the same quantity, but at least ephemerally, episodically, it’s there.”

Still, the water is so incredibly briny that it’s difficult to imagine microbes being able to survive with the harsh fluid.

In the meantime, where exactly the water comes from, how it’s released, and how it gets back into the soil to repeat the cycle every year remain open questions, the scientists said. Such questions could be answered by a future orbiting mission to Mars, Ehlmann added.

(c)2015 Los Angeles Times. Distributed by Tribune Content Agency, LLC.

Portions of the Martian surface shot by NASA’s Mars Reconnaissance Orbiter show many channels from 1 meter to 10 meters wide on a scarp in the Hellas impact basin, in this photograph taken January 14, 2011 and released by NASA March 9, 2011. REUTERS/NASA/JPL-Caltech/Univ. of Arizona/Handout

Are E-cigarettes A ‘Gateway’ To Teen Smoking? A New Study Investigates

Are E-cigarettes A ‘Gateway’ To Teen Smoking? A New Study Investigates

By Amina Khan, Los Angeles Times (TNS)

LOS ANGELES — Even though teenage smoking rates have plunged in recent decades, teen use of electronic cigarettes has been on the rise in the last few years. Now, a new study involving more than 2,500 students at 10 Los Angeles schools has found that teens who began using e-cigarettes were far more likely than their peers to start smoking traditional cigarettes and other combustible tobacco products.

Although they don’t establish a causal link, the findings published in the Journal of the American Medical Association have some experts worrying that e-cigarettes might lead more young people to take up the habit.

“What is extremely worrisome is that these findings further indicate that e-cigarette use by our nation’s youth, which is a major concern in itself, may also be a gateway to smoking,” American Heart Association Chief Executive Nancy Brown said in a statement. “This new study truly underscores just how dangerous of a habit e-cigarette use can be, especially if it is leading to teens taking up additional tobacco products.”

E-cigarettes heat a liquid laced with nicotine and other chemicals to generate a vapor that can be inhaled. That method, known as “vaping,” presumably sounds better than traditional combustible tobacco products, which are burned to produce a smoke filled with chemicals, many of which are known to cause cancer. The problem is, there isn’t enough evidence yet to say whether, on balance, the devices are helpful or harmful, scientists say.

“E-cigarettes raise many questions for which there are few answers,” Dr. Nancy Rigotti of Massachusetts General Hospital, who was not involved in the paper, wrote in an editorial. “The evidence base is limited because e-cigarettes entered the marketplace without being regulated as either drugs or devices.”

Many think that e-cigarettes might allow smokers to transition away from traditional cigarettes, which contain cancer-causing substances. Others argue that e-cigarettes, which often appear to be marketed to youths, could act as a sort of “gateway device” into smoking traditional cigarettes, full of those carcinogenic materials.

That’s a serious matter, given that nearly 90 percent of adult cigarette smokers first started smoking before age 18, according to the Centers for Disease Control and Prevention. A recent study showed that the number of high school smokers tripled from 2013 to 2014, and another showed that teens who vaped also smoked regular cigarettes.

But such studies have looked at a snapshot of these two behaviors, and have not watched to see how they change over time _ which would better describe the relationship between the two activities.

So for this study, a team led by researchers at the University of Southern California’s Keck School of Medicine tracked the behavior of 2,530 students attending L.A. high schools who said they had never before used any combustible tobacco products. The scientists focused on high school freshmen, given that ninth-graders, fresh out of middle school and now exposed to new pressures and older adolescents, are at a critical turning point in their lives.

“The first year of high school is a vulnerable period for initiating risky behaviors,” the JAMA study authors wrote.

The researchers asked the students whether they had ever tried e-cigarettes _ 222 had already tried e-cigarettes at that time. Then they followed up six months later and 12 months later to see if they had ever smoked regular cigarettes or other tobacco products (including cigars and hookah) during the previous six months.

The scientists found that 30.7 percent of students who had ever used e-cigarettes at the start of the study had also used combustible tobacco products at the six-month mark. In the same time period, only 8.1 percent of those who had never used e-cigarettes at the start of their freshman year had smoked tobacco. This pattern held at the 12-month mark as well.

The findings show a link between the two habits, but not a cause. That means it’s possible that there’s some other underlying factor that might be contributing to both behaviors. And the results can’t distinguish between students who may have just tried a few cigarettes and those who ended up as regular smokers, Rigotti noted.

“The latter is the greater concern, and the current study cannot determine whether e-cigarette exposure was associated with that outcome,” she wrote. “Similarly, the single exposure measure, lifetime e-cigarette use, did not permit the authors to look for a dose-response relationship between the degree of prior e-cigarette use and subsequent smoking, which could have strengthened a causal inference.”

Further work will be needed to determine whether there is a cause-and-effect relationship between vaping and smoking, the study authors said.

Regardless, experts said, this doesn’t mean that children should be taking up e-cigarettes at all. But many e-cigarette products appear to be marketed toward youths, they added.

“Knowing the long-term consequences of tobacco use, it is mind boggling to think that anyone would assume e-cigarette use is acceptable among children, when for many it can function as an entry drug,” Dr. Kim Allan Williams, president of the American College of Cardiology, said in a statement. “This research provides one more piece of evidence that what common sense tells us is likely true: inhaling an addictive chemical is not good for anyone.”

Brown, of the American Heart Association, urged the federal government to take action to regulate the products.

“These findings are yet another wake-up call to the Food and Drug Administration that final regulations are needed now to protect our kids from tobacco,” Brown said in a statement.

(c)2015 Los Angeles Times. Distributed by Tribune Content Agency, LLC.

Mars Rover Curiosity Offers Tantalizing Taste Of 2-Tone Mineral Veins

Mars Rover Curiosity Offers Tantalizing Taste Of 2-Tone Mineral Veins

By Amina Khan, Los Angeles Times (TNS)

Climbing up Mt. Sharp in the middle of Gale Crater, NASA’s Mars rover Curiosity has discovered a two-tone vein of minerals that reveal multiple episodes of water flowing through rock — even after the lake that once filled the bottom of the crater had ceased to be.

The rover’s discovery points to an even more complex, and perhaps long-lived, watery environment on the Red Planet.

“Not only does this help us try to understand the chemistry of the rocks that we measure in the region, but on a different sort of scale it tells us that fluids were around on Mars for a long time,” said Linda Kah, a sedimentary geologist at the University of Tennessee, Knoxville, and a member of Curiosity’s science team.

The duo-tone deposits, at a spot called Garden City, sit some 39 feet above the lower edge of the Pahrump Hills outcrop, which is part of the basal layer of the 3-mile-high Mt. Sharp. They feature both light and dark regions. They rise about 2.5 inches above the rock surface like ridges, because the rock that once surrounded them has worn away. These kinds of veins are formed when fluid flows through cracks in a rock and leaves some minerals behind.

Most veins have been bright and light-colored, Kah said, often filled with calcium sulfate. On Earth, such mineral deposits are often associated with salty water. But the dark deposits were somewhat unexpected, she said.

The dark parts often seem to line either side of the white veins, rather like an ice cream sandwich — a description Kah’s 10-year-old son Douglas came up with while looking over his mother’s shoulder at images of the deposits.

“I think they’re incredibly gorgeous and beautiful,” she said.

Whether appetizing or attractive, the two different tones are scientifically telling. Researchers look at Martian rocks in part to see how water (and the stuff in the water) may have affected a particular rock during a particular era. But if the same rock is getting soaked with very different kinds of water sources over time, then it may show a confusing mix of traits from a long period in which the environment dramatically changed over and over again.

That’s why the mineral veins are so helpful. The deposits in the cracks can look very different from the surrounding rock because they were formed much later than the rock itself. So while the rock’s chemistry and mineralogy will have been affected by multiple environments, the mineral vein offers a snapshot of at least one individual era in the Red Planet’s history.

In this case, this mineral vein actually offers snapshots into three environments. At first the scientists thought there were two different epochs, represented by the light and dark deposits, but it turns out that some dark spots are chemically very different from other dark areas.

“It was really very exciting for us,” Kah said. “Now we’ve just added complexity, so it makes it more fun to figure it out in the long run.”

The scientists think this environment existed long after the lake that once filled the bottom of Gale Crater dried up for good, and that these deposits were created by water under a significant amount of rock — enough to exert the kind of pressure that would force the fluid to push through cracks in the stone.

It’s also unclear how hot or cold or acidic or salty this water was; the fluid’s chemistry could have been very different from the potentially potable liquid in that long-gone lake.

But it’s still quite possible that microbial life, if it ever existed, could have thrived in this environment, just as they thrive in the rock fractures at the hot springs of Yellowstone National Park, she added.

(c)2015 Los Angeles Times, Distributed by Tribune Content Agency, LLC

Image Credit: NASA/JPL-Caltech/MSSS

Liberal Or Conservative? Brain’s ‘Disgust’ Reaction Holds The Answer

Liberal Or Conservative? Brain’s ‘Disgust’ Reaction Holds The Answer

By Amina Khan, Los Angeles Times (MCT)

Think your political beliefs arise from logic and reason? Think again. A team of scientists who studied the brains of liberal, moderate and conservative people found that they could tell who leaned left and who leaned right based on how their brains responded to disgusting pictures.

The findings, published in Current Biology, show that the brains of liberals and conservatives may indeed by wired differently — and shed light on the biological factors at play in political beliefs.

Biology and politics have long been seen by many researchers as two very separate realms. Some argue that biology is irrelevant to political questions, or that the links between the two are murky or oversimplified.

“Despite growing evidence from various fields, including genetics, cognitive neuroscience and psychology, many political scientists remain skeptical of research connecting biological factors with political ideology,” the study authors wrote.

But many of the same subjects at issue in certain political ideologies — attitudes toward sex, family, education and personal autonomy, for example — have an emotional component as much as a logic-based one. And some research has indicated that political leanings can be inherited (much in the same way that height can inherited but modified, affected by a number of factors from nutrition to the environment).

To probe this controversial question, a team led by Virginia Tech scientists called upon 83 volunteers who took a test to determine what their political leanings were. Then, while sitting in the fMRI machine, they looked at 80 different images — 20 each of disgusting, threatening, pleasant or neutral images. The researchers watched how the participants’ brains reacted to each of those images while in the machine. Later, they were asked to rate how disgusting, pleasant or threatening each image was.

When shown a disgusting image — particularly one of a mutilated animal body — the conservatives’ brains reacted more strongly, and in different ways, compared with the liberals’ brains.

“Although our results suggest that disgusting pictures evoke very different emotional processing in conservatives and liberals,” the authors wrote, “it will take a range of targeted studies in the future to tease apart the separate contribution of each brain circuit.”

The difference between the two groups was stark in spite of the fact that, oddly enough, these neural responses didn’t match the conscious ratings that participants gave those pictures.

Other images, whether threatening or pleasant or neutral, didn’t show the same link, but it’s possible that pictures of threats don’t register the same way a real threat would, the authors pointed out.

“People tend to think that their political views are purely cognitive (i.e., rational),” the study authors wrote. “However, our results further support the notion that emotional processes are tightly coupled to complex and high-dimensional human belief systems, and such emotional processes might play a much larger role than we currently believe, possibly outside our awareness of its influence.”

Certainly politics is more than a few (possibly subconscious) emotional reactions; life history and experience also affect political beliefs, the study authors wrote. But it does raise some questions about whether partisans will need to develop new strategies to reach across the political aisle.

“Would the recognition that those with different political beliefs from our own also exhibit different disgust responses from our own help us or hinder us in our ability to embrace them as co-equals in democratic governance?” the researchers wrote. “Future work will be necessary to answer these important questions.”

AFP Photo

‘Django Unchained’ Actress Detained For ‘Basic Police Work,’ LAPD Says

‘Django Unchained’ Actress Detained For ‘Basic Police Work,’ LAPD Says

By Amina Khan, Los Angeles Times

A Los Angeles police official defended the actions of officers who detained “Django Unchained” actress Daniele Watts as “basic police work” amid claims that she was mistreated.

According to the police account of the incident, officers were responding to a 911 complaint that a couple was engaged in indecent exposure last week inside a silver Mercedes-Benz with the door open.

Patrol officers and a sergeant from the North Hollywood Division responded to the 11900 block of Ventura Boulevard in Studio City and “located two individuals that matched the description of the suspects, and they were briefly detained,” police said in a statement.

Watts and her companion, Los Angeles chef Brian James Lucas, were subsequently released after an investigation revealed no crime had been committed.

Video posted on social media shows Watts handcuffed, wearing a T-shirt, gym shorts, and athletic shoes, telling an officer, “You guys came and grabbed me … for no reason.”

“As I was sitting in the back of the police car, I remembered the countless times my father came home frustrated or humiliated by the cops when he had done nothing wrong,” Watts, who is African American, wrote on her public Facebook page.

But LAPD Capt. Stephen Carmona of the North Hollywood area station defended the officers, saying they were doing due diligence when they detained Watts after she did not give them identification.

“That’s just basic police work. It could be a vandalism suspect in an alley,” Carmona said. “The vandalism may be done, but they’re still going to investigate the incident.”

Still, Carmona said the LAPD would fully investigate the allegations made by Watts and Lucas, who is white.

“We take all of these things really seriously, and we’re going to ask the hard questions,” Carmona said.

Watts and Lucas did not respond to The Times‘ requests for comment. Watts’ manager, Shepard Smith, declined to comment.

AFP Photo/Kevork Djansezian

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NASA’s Mars Rover Curiosity Finally Arrives At Mount Sharp

NASA’s Mars Rover Curiosity Finally Arrives At Mount Sharp

By Amina Khan, Los Angeles Times

After wandering in the Martian desert for 25 months, NASA’s Curiosity rover has finally arrived at its promised land: the base of Mount Sharp, the 3-mile-high mound in the middle of Gale Crater.

The arrival marks the beginning of the Mars Science Laboratory rover’s original mission: to read the mountain’s clay-rich lower layers like pages in a history book, pages that could reveal an array of life-friendly environments on the Red Planet.

“We have finally arrived at the far frontier that we have sought for so long,” project scientist and California Institute of Technology geologist John Grotzinger said Thursday.

Getting to Mount Sharp has been a long time coming. The trip was delayed in part by a detour the rover took to look at a promising spot called Yellowknife Bay. Although it cost the team at Jet Propulsion Laboratory about half a year, the gamble paid off; rocks drilled there revealed a smorgasbord of chemical elements that would have been suitable for microbial life, if it ever existed.

Now that the scientists know habitable environments did exist on the Red Planet, part of the next step will be looking for those particular environments that have a higher likelihood of preserving organic molecules, Grotzinger said.

The rover is closing in on a spot known as Pahrump Hills, an outcrop that wasn’t on the original itinerary — a happy outcome of the detour Curiosity took to avoid sharp rocks that had been causing an alarming amount of damage on the rover’s thin wheels. This spot will now be the gateway to Mount Sharp, and it probably holds Curiosity’s first official drilling target. Grotzinger said the rover would make it there in the next week or two.

The scientists are particularly interested in a stretch of rock known as the Murray Formation, which it will cross en route to its original stopping point, Murray Buttes. Kathryn Stack, Curiosity rover mission scientist, pointed out that the Murray Formation could provide an unprecedented wealth of information about the history of habitable environments on Mars. After all, the Yellowknife Bay formation where Curiosity found its first life-friendly spot was only 5 meters thick, representing perhaps thousands to hundreds of thousands of years of sedimentary deposits. The Murray Formation, by contrast, is 200 meters thick.

“We potentially have millions to tens of millions of years of Martian history just waiting for us to explore,” Stack said.

The hard part, scientists said, will be deciding how much time to devote to Pahrump Hills, Murray Buttes and the next interesting unit up the slopes, called Hematite Ridge. Grotzinger said he was particularly interested in the silicon in the upcoming rocks, because the element’s distribution can often signal the movement of water.

Mission officials also responded to criticism from a NASA Planetary Senior Review panel report released this summer. The report contended that the plan to explore Mount Sharp did not make good use of the rover’s instruments, calling it “a poor science return for such a large investment in a flagship mission.”

“I think the principal recommendation of the panel is that we drive less and drill more,” Grotzinger said, and he said that’s not far from what they are going to end up doing. “I think that the recommendations of the review and what we want to do as a science team are going to align, because we have now arrived at Mount Sharp, we are going to do a lot more drilling.”

Photo via WikiCommons

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Welcome To Laniakea, Your Galactic Supercluster Home

Welcome To Laniakea, Your Galactic Supercluster Home

By Amina Khan, Los Angeles Times

LOS ANGELES — Home, supercluster home. Astronomers studying the skies have found that our galaxy, the Milky Way, is part of an enormous supercluster of galaxies that has been named Laniakea, which comes from the Hawaiian words for “immeasurable heaven.”

Laniakea, described in the journal Nature, stretches roughly 500 million light years across and holds 100,000 galaxies with the mass of a hundred million billion suns. This supercluster, scientists said, provides a whole new lens on the mysterious internal dynamics of such giant clusters, the biggest structures in the universe.

The universe has a certain order, defined by gravity: Planets circle stars, which spin around in galaxies, which hang out together in large clusters, which are nestled in gargantuan superclusters. These superclusters give the cosmos its large-scale structure — matter concentrates in massive, dense nodes and thin tendrils connect those nodes across the empty spaces in between.

Even though superclusters define the nodes of this cosmic web, scientists know very little about how they work. Until now, they didn’t even know where exactly our own Milky Way lives — just that we’re in a local group of at least 54 galaxies, which is itself part of a larger conglomeration long called the Virgo (or Local) Supercluster.

It’s a little like knowing your street address without knowing which city you live in — which sounds like a pretty basic problem, but has proved deeply challenging to solve.

“This is what I’ve been doing for a long time, trying to understand where we live,” said lead author R. Brent Tully, an astronomer at the University of Hawaii in Honolulu.

The giveaway is gravity. Gravity holds superclusters together, so watching the movements of galaxies speeding around their neighborhoods could help define a supercluster’s borders.

Here’s the problem. The universe is expanding faster and faster, because of a mysterious force called dark energy. This mucks up the speed readings: Scientists don’t know how much of a particular galaxy’s movement is because of the inward pull from the gravity of a cluster, and how much is because of the outward pull of the universe expanding faster and faster.

So a team of cosmic cartographers used the Superflows-2 database, a catalog of the motions of galaxies, to tease apart these movements. For each of more than 8,000 galaxies, they subtracted the expansion-related movement from the overall motions — leaving only the local, gravitationally driven movement.

The researchers found that the galaxies were flowing along these long, beautiful lines, many of them toward a gravitational dense basin of galaxies known as the Great Attractor. The boundary between those flowing toward this spot and those flowing away marked the edges of the galaxy supercluster.

It’s like watching a watershed where the flows divide, Tully said.

“If you’re standing at a certain place at the divide, water might be going in two different directions — one going into the Mississippi basin, one going off to the Great Lakes,” Tully said.

The Milky Way sits in a backwater among these flowing galaxies, near a far edge of the supercluster. In fact, the whole Virgo Supercluster is just a small fraction of the Laniakea Supercluster.

“The Local Supercluster, we now see quite clearly, is just an appendange on Laniakea,” Tully said. “It’s like a suburb in a city of a metropolitan area.”

Elmo Tempel, an astronomer at Tartu Observatory in Estonia who was not involved in the paper, praised the findings.

“This is the first clear definition of a supercluster,” Tempel wrote in a commentary. “The downside of it is that it requires dynamical information that is available only for the nearby universe.”

Understanding the dynamics of our own supercluster could help shed light on the large-scale forces at work in the universe, Tully said, particularly dark matter, the mysterious unseen mass whose gravity holds such enormous structures together, and dark energy, the strange force that is tearing them inevitably apart.

Photo via WikiCommons

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Mars Rover Opportunity Breaks The Off-World Driving Record

Mars Rover Opportunity Breaks The Off-World Driving Record

By Amina Khan, Los Angeles Times

Opportunity, the little rover that could, has broken a 41-year-old driving distance record that’s out of this world. The decade-old NASA Mars rover has crossed the 25-mile mark, surpassing the 24.2-mile record held by the Russian moon rover Lunokhod 2.

Not too shabby for a rover that landed on the Red Planet in 2004 with a 90-day mission and an odometer geared for a roughly 0.6-mile drive, said John Callas, the mission’s project manager at NASA’s Jet Propulsion Laboratory in La Canada Flintridge, Calif.

“No one in their wildest dreams thought the rover would last this long,” Callas said. “People made bets early on — ‘Maybe we can get to the first Martian winter,’ ‘Maybe we can get two years out of it’ — but no one thought that it would last this long.”

No one’s betting against Opportunity now. It may be aging, with an arthritic elbow and a somewhat disabled front wheel, but it has long outlived its twin rover, Spirit, and lasted roughly 40 times as long as it was supposed to.

The previous record-holder for distance, the Lunokhod 2, was sent loping around the moon’s surface by Russia in 1973. It covered 24.2 miles in less than five months — speedy compared with Opportunity’s 10-plus years. But NASA’s Martian rover was the tortoise to Lunokhod 2’s hare, slowly and inexorably closing the distance.

Opportunity’s extra miles have allowed its handlers to make remarkable discoveries, because the robotic explorer has been able to venture far outside its landing site. Though it discovered hints of past water soon after landing in Eagle Crater, the water was acidic and unsuitable for life. Only after leaving its landing site and arriving at Endeavour Crater did the rover discover signs of neutral, drinkable water — a key ingredient for life-friendly environments.

If Opportunity can do about 1.2 more miles, it will reach Marathon Valley (so named because it marks the 26.2-mile point). The valley holds layers of rock rich in clay that could give new insight into the Red Planet’s geologic story. In that way, it’s a little like Mount Sharp, the 3-mile-high mound in the middle of Gale Crater targeted by NASA’s bigger, more advanced Mars rover, Curiosity, which touched down in 2012. Curiosity’s tools could help it read the mountain’s clay-rich layers like pages in a book, whose chapters could reveal ancient, life-friendly environments.
But in some ways, Callas said, Opportunity’s target is even better.

Mount Sharp will give Curiosity a window on Mars as it was about 3.5 billion years ago. But Marathon Valley’s layers could show Opportunity what the Red Planet looked like about 4 billion, even up to 4.5 billion years ago.

“The geology is older and more significant in terms of establishing the early habitability of Mars,” Callas said. The clays could come from very early days, he said, a time when Mars could have been warm and wet — with similar conditions to early Earth when life here first began to emerge.

And even though Curiosity’s high-tech tool belt will allow it to explore its target in ways that Opportunity cannot, there’s no knocking the “classical field geology” the older rover can do with its cameras and its rock abrasion tool, Callas said — analogous to a human geologist’s eyes and trusty rock hammer.

So when will Opportunity finally kick the bucket?

“You know, no one really knows. The only thing I can say is that with each passing day we get a bit closer to that end,” Callas said. “It could happen at any moment … or it could just keep plodding along. So we treat each day as a valuable day and keep exploring.”

Photo via WikiCommons

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Giving Auguste A Chance To Hear

Giving Auguste A Chance To Hear

By Amina Khan, Los Angeles Times

LOS ANGELES — Auguste is 3 years old, a charmer with big blue eyes, long lashes, and a playful smile. He’s wearing a T-shirt that says “Make some noise” and fiddling with his Etch A Sketch in a hospital exam room.

But when a doctor reaches toward his temple, he quickly releases the knobs and tilts his head. He knows what they’re looking for. Behind each ear, under the skin, are cochlear implants — surgically implanted devices meant to help process sound.

But they didn’t help Auguste.

He was born without an auditory nerve, the wire that ferries sound from the ear to the brain. He points out planes in the sky but can’t hear their engines roar. He’s never heard the voices of his 4-year-old sister or 1-year-old brother. He doesn’t know the sound of his own name.

Now, a team of Los Angeles doctors and researchers believes it can help Auguste hear. But the device the team is testing will require surgeons to go much deeper into Auguste’s skull, all the way to the brain.

Sophie Gareau, Auguste’s mom, often tears up when she thinks about what’s ahead.

“He’s so perfect, you know?” she says. Her voice breaks. “I don’t want anything to happen to him. But I am so convinced that it’s going to work.”

Sophie realized something was off when Auguste was 6 months old: Her baby wasn’t babbling. Doctors in Montreal said he was fine. She insisted otherwise, but it was nearly a year later before audiologists played sounds as loud as an airplane engine in the toddler’s ear and confirmed what his French-Canadian parents had suspected: Auguste was profoundly deaf.

“I think it takes a moment to sink in and then you cry for a week,” Sophie said.

Audiologists put him on track for the cochlear implant, which places electrodes in the snail-shaped cochlea, part of the inner ear, to stimulate the auditory nerve. It’s a common procedure for deaf children: About 38,000 children in the United States have received them.

But the surgery didn’t work. Auguste had a cochlea, doctors discovered, but no auditory nerve to deliver sound to the brainstem.

Sophie and her husband, Christophe Majkowski, were crushed, but they focused on the positive. “He’s perfectly healthy, and he’s smart and he’s quick,” said Sophie, who shares her son’s big blue eyes and constantly chats with him in sign language.

She’d heard about something called an auditory brainstem implant, or ABI. The device uses an external processor on the ear to send sound to a surgically implanted electrode array. A doctor warned her against it.

“He had mentioned that only the Italians were doing it and they were ‘cowboys,’ which in French means ‘crazy people,’ ” she said.

The Italian in question was Vittorio Colletti, who began putting the devices in healthy deaf patients in the late 1990s at the University of Verona. This was unheard of at the time: There had to be an urgent reason — such as removal of a dangerous tumor — to perform such a risky surgery.

Colletti was criticized. But he began reporting incredible results; some patients with the device could even conduct business on the phone, without lip-reading.

The medical community was skeptical. So Colletti invited Robert Shannon, who helped develop the modern brainstem implant while working as a medical researcher at the House Research Institute in Los Angeles, to see for himself.

Shannon spent hundreds of hours testing patients in Italy.

“I was astounded,” said Shannon, who now works at USC. “It was even better than he said.”

A team of researchers that included Shannon wanted to introduce the procedure to children in the United States. But a risk-averse Food and Drug Administration denied the team’s initial request, said USC audiologist Laurie Eisenberg, one of the lead scientists.

“After all,” Eisenberg said, “it is brain surgery in children.”

After some key changes in FDA personnel, the team received the go-ahead in 2012. In spite of several setbacks, the team pressed on, because the National Institutes of Health had agreed to pay for the team’s clinical trial.

Auguste is its first patient.

Auguste lies unconscious in the operating room at Children’s Hospital Los Angeles, a blue sheet covering his body. The only part of him visible is a small square where the three surgeons are operating — their window into Auguste’s brain.

Pediatric neurosurgeon Mark Krieger stands over this tiny red window, gloved hands at work. Marc Schwartz, a neurosurgeon with the Los Angeles-based House Clinic, speaks in a voice muffled by the mask they all must wear. His colleague Eric Wilkinson, one of the lead scientists, trains a plastic-wrapped microscope on the exposed flesh.

The surgeons cut through skin, saw through bone, and snip through the dura, the brain’s protective covering. They drain cerebrospinal fluid so that the cerebellum relaxes, allowing them to move past the bulging tissue and reach the brainstem. Occasionally a spurt of blood runs across the opening, but the surgeons don’t flinch.

Colletti, the “cowboy” who pioneered the procedure, is sitting nearby. He has flown in from Italy to see the clinical trial begin. He can’t wield a knife; all he can do is offer advice as he watches Auguste’s brain on a large screen.

Schwartz knows the path to the cochlear nucleus, the spot on the brainstem where the ABI will go. He’s seen Colletti perform the procedure in Italy about half a dozen times. He follows the ninth cranial nerve to the boundary between the cerebellum and brainstem, then looks for a tiny nook called the lateral recess. That’s where the cochlear nucleus should be.

But it isn’t.

“There’s nothing there. There’s no hole there,” Schwartz says. “No hole. Not even anything that looks like a hole. Remotely.”

The chatter in the room has dropped to hollow silence, punctuated by the harsh beep of the monitors.

Schwartz retraces his steps, over and over. No luck. The surgeons debate what to do next. If they can’t find the lateral recess, they can’t put the device in.

Wilkinson urges him forward, but Schwartz is worried.

“I’m just afraid of hurting the kid,” he says.

At last, Schwartz finds the entrance. Over several minutes, he carefully inserts the 8-millimeter-long electrode array into the right spot.

“Bravo,” Colletti says. “Bravo, bravo!”

After the roughly six-hour operation, the doctors find Auguste’s parents in a waiting room. The surgery went well, they say. Auguste will be awake soon.

Christophe and Sophie hug each other tightly. When the surgeons are gone, she lets out a whoop, edged with exhaustion.

There are a few scary days for Auguste’s parents. Soon after the surgery, Sophie discovers blood seeping onto his pillow.

A week passes before Auguste can walk again. A few weeks later, he’s playing in the sand at Venice Beach with his family, a new haircut outlining the pink crescent scar behind his ear.

Inside Auguste’s head, his brain is healing and fibrous tissue is growing around the device. Outside, he’s flailing at his older sister, Daria, as they both try to climb onto their dad’s back. Christophe rears like a horse and they slip into the sand, giggling and out of breath.

Auguste sits at a toy-filled table at USC’s Keck School of Medicine. After a month of recovery, it’s time to find out whether the surgery worked.

Margaret Winter and Jamie Glater scrunch around the kid-sized table. They’re known as “child whisperers”; because deaf children can’t say exactly what they’re hearing, the USC audiologists have to be able to read their reactions, such as a quick glance or a sudden stillness.

As Auguste plays with his trucks, Winter uses her computer to remotely activate individual electrodes on the device, each of which represents a different pitch range. If the device works, Auguste should hear these simple beeps.

Auguste is rolling a toy monster truck across the table. As the beep sounds, he freezes, mid-car crash. Something’s happened.

Glater makes a crooked L with her fingers, the thumb pointed at her ear. “Listening! You’re listening!” she says. Auguste searches their faces, then goes back to his toys.

Delighted, the audiologists go through several more electrodes, dialing up the electrical signal on each until they see a clear reaction. Then, it’s time to try a human voice. They turn on the microphone.

“Bap-bap-bap-bap,” Glater says. Every time she says the strong syllables, Auguste drops a token in a Connect Four grid, as he’s been trained to do. The adults cheer.

Winter turns the signal up. Auguste winces — the way you do when a sound is too piercing — and brings his hand to his head, then runs into Sophie’s open arms. He shakes his head so hard, the earpiece flies off.

That’s perfectly normal, Winter tells the parents. It’s a completely new experience — more of a sensation than a sound at first. Whatever he felt, it “penetrated his world,” Winter says.

Photo: Los Angeles Times/MCT/Brian van der Brug

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Giant Volcano With Glacier On Mars May Have Been A Nice Place For Life

Giant Volcano With Glacier On Mars May Have Been A Nice Place For Life

By Amina Khan, Los Angeles Times

If life existed on Mars in the recent past, the best spot for it could have been on a giant volcano once encrusted with a glacier, according to a team of Brown University scientists using data from NASA’s Mars Reconnaissance Orbiter.

Microbial life could potentially have thrived for a time at the foot of Arsia Mons, a giant volcano about twice as tall as Mount Everest, while the dinosaurs were just coming into their own on Earth, according to the study published in the journal Icarus.

Though an active volcano may not sound particularly inviting, this combination of ice and heat would have contained massive, sheltered pockets of water — from melted ice — that could have lasted for hundreds or even a few thousand years.

“I was very excited,” lead author Kathleen Scanlon, a doctoral student and geologist at Brown University, said of the telltale signs left on the Martian surface that led to the team’s conclusions. “It’s all a really nice suite of land forms that together all point to the exact same process. So that was really cool.”

The findings come as NASA and other space agencies send more spacecraft and robots to the Red Planet to better understand how life-friendly Mars was in the past — and whether certain spots were better suited for living things than others.

Recent research has shown that the northwest side of Arsia Mons may have been covered in glacier ice, judging by marks in the terrain that resemble those left by glaciers in Antarctica’s McMurdo Dry Valleys. Around that time, about 210 million years ago, the volcano was active, spewing out lava from beneath the ground and melting some of the thick layer of glacial ice above.

Scanlon looked for certain shapes in the lava that would reveal the conditions under which the lava was coming out. She found a number of striking forms, including pillow-like lava, which extrude into giant rounded globules. On Earth, these pillows form under immense pressure at the bottom of the ocean. On Mars, it could mean the lava was under extreme pressure because it was squeezing out from underneath a glacier.

Two of the liquid bubbles caused by subsequent melting in the solid glacial ice would have held about 40 cubic kilometers of water each, making each of them roughly a third the size of Lake Tahoe. The water in these deposits could have remained liquid for centuries or more, the researchers said.

Microbes trapped in a subglacial lake, in freezing temperatures, total darkness and high pressures may sound extreme, but organisms do it on Earth too. A recent study of ice cores from a subglacial lake in Antarctica found DNA from a variety of microbes living more than 2 miles beneath the ice.

Of course, even a potentially life-friendly zone like Arsia Mons would not have lasted long on geological timescales. At its best, it could have potentially hosted microbes that had already emerged billions of years before, when Mars might have been warmer and wetter.

So the most important thing to understand is whether Mars was habitable more than 3.5 billion years ago, very early in its history, Scanlon noted. If not, then Arsia Mons’ habitability is probably moot. NASA’s Curiosity rover recently dug up some rock in Gale Crater and found some very watery environments rich in chemical building blocks for life. Just before the launch of the atmosphere-testing MAVEN mission last year, NASA released a stunning video of a past Mars, filled with puffy clouds and blue lakes.

But whether much of Mars was so life-friendly, and how long this wet era may have lasted, is up for debate. The less common these life-friendly spots were, and the shorter-lived they were, the less likely that life was able to emerge on the Red Planet. For now, the jury’s out on that mystery.

“If we can confirm that there was life around then, then our next question is, how long was it able to survive, and could there still be dormant microbes lying somewhere around on the surface?” Scanlon said. “I think Arsia Mons would be a good site to answer questions like that — if that does become a question.”

Photo: Luke Bryant via Flickr

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Gravitational Waves From Just After Big Bang Show How Universe Grew

Gravitational Waves From Just After Big Bang Show How Universe Grew

By Amina Khan, Los Angeles Times

Nearly 14 billion years ago, in a tiny fraction of a second after the Big Bang, the universe suddenly expanded from smaller than an atom to 100 trillion trillion times its original size, faster than the speed of light. This mysterious period, known as cosmic inflation, had been theorized but never confirmed.

But now, scientists using telescopes at the South Pole say they have discovered the first direct evidence for this incredible growth, in the signature of gravitational waves.

“It’s amazing,” said experimental cosmologist John Carlstrom of the University of Chicago, who leads the competing South Pole Telescope project. “Everyone in my field, what we’re thinking of doing in the future, we have to all rethink. This is an amazing milestone.”

The groundbreaking results from the BICEP2 team confirm a long-held theory about the universe’s earliest moments and show that what we can see with visible light is just a tiny fraction of the cosmos, which may extend far beyond the edges we know of today. And they confirm the sometimes uneasy relationship between Einstein’s general theory of relativity, which works on large scales, and quantum mechanics, which governs the infinitesimally small scales.

It’s a discovery that could well be worthy of a Nobel Prize, said researchers who were not involved in the project.

“This is a watershed moment,” said California Institute of Technology astrophysicist Jamie Bock, one of the lead scientists on the BICEP2 collaboration.

The researchers used telescopes in Antarctica to stare at the cosmic microwave background radiation — a faint glow of low-energy light left over from the Big Bang that permeates the entire universe — and analyzed the light for signs of polarization. Swirling patterns left in the polarized light would be a clear sign that gravitational waves had left their mark.

Many theorists have long thought that if the universe had suddenly expanded, gravitational waves would have left a rippling mark on the structure of the universe. The discovery of these gravitational waves confirms that theory, but scientists still don’t agree on exactly what triggered inflation in the first place. And whatever inflation was, they do think that it was a mysterious, repulsive force — rather like the dark energy that pervades the universe today and is causing it to expand — but far, far more powerful.

Photo via Wikimedia Commons

Mercury Is Slowly Shrinking, Scientists Say

Mercury Is Slowly Shrinking, Scientists Say

By Amina Khan, Los Angeles Times

They say the world is getting smaller — and in Mercury’s case it’s literally true. Though it’s already the tiniest planet in the solar system, scientists say Mercury is still shrinking — and signs of that contraction can be clearly seen in distortions of the planet’s searing surface.

The findings, published in Nature Geoscience, solve a decades-old mystery about the evolution of the little planet’s interior and provide scientists a window into the long-term changes that affect other worlds that don’t have Earth-like plate tectonics.

“Determining the extent to which Mercury contracted is key to understanding the planet’s thermal, tectonic and volcanic history,” the study authors, led by Paul Byrne of the Carnegie Institution of Washington, wrote in the paper.

Mercury is a weird little world. As the solar system’s innermost planet, it sits less than 36 million miles from the sun — less than two-fifths of the Earth-to-sun distance. It’s mostly made up of its heavy iron core, which has about a 1,255-mile radius and leaves a thin rind of just 261 miles for its crust and mantle. Even though it’s unbearably hot, the planet also hosts permanently shadowed regions inside craters that are among the coldest spots in the solar system.

Researchers have long thought that Mercury must be shrinking, because as the planet cools, and the liquid iron core turns solid over time, it contracts. If so, signs of deformation should show up on the planet’s surface — like a plump, smooth-skinned grape that dries up, shrinks and turns into a wrinkly raisin.

Sure enough, when NASA’s Mariner 10 spacecraft flew by the planet in 1974 and 1975, it discovered strange, snaking “lobate scarps” on the surface of the planet. Those scarps, which are Mercury’s version of mountain ranges, were the signs that the planet had shrunk, causing its rocky skin to deform.

But Mariner 10 imaged only 45 percent of the planet, and scientists could account for only about 0.5 to 2 miles of shrinkage in the radius. The models said that Mercury’s radius should have shrunk roughly 3 to 6 miles over the last 4 billion years, since its crust solidified. Were the models wrong? Or was it simply that we hadn’t seen enough of Mercury?

NASA’s MESSENGER spacecraft, which flew by the planet in 2008 and 2009 and entered Mercury’s orbit in 2011, solved the mystery by mapping the remaining 55 percent of the planet that Mariner 10 missed. Scientists found that the lobate scarps covered the whole globe randomly — and that these weren’t the only signs of shrinkage. The scientists found wrinkle ridges all over Mercury’s volcanic plains, and though they’re not as high or as dramatic as those lobate scarps, they’re also a reliable sign that Mercury has been contracting, and can help researchers measure how much volume has been lost.

Based on this new view of Mercury, the researchers found that the planet’s radius had probably shrunk about 3 to 4.3 miles since its crust solidified — safely within range of the theoretical predictions.

“The findings provide a global framework for investigations into Mercury’s surface and interior evolution,” planetary scientist William McKinnon of Washington University in St. Louis wrote in a commentary on the paper.

All planets, Earth included, are cooling down over time — but the findings don’t apply to Earth because our home planet has constantly shifting tectonic plates and Mercury is a one-plate planet. Still, these wrinkly, mountain-like features have also been seen on the moon and on Mars, and Mercury could make it a model for what happens to other single-plate planets.

“Mercury provides an example of what may really happen to a planet that is shrinking,” McKinnon wrote.

Photo: Lunar and Planetary Institute via Flickr