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  • richardmitnick 10:17 am on December 12, 2014 Permalink | Reply
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    From NYT: “Looking to Mars to Help Understand Changing Climates” 

    New York Times

    The New York Times

    DEC. 8, 2014

    NYT Dennis Overbye Older
    DENNIS OVERBYE

    Ten thousand times a hundred thousand dusty years ago
    Where now it stands the Plain of Gold did once my river flow.
    It stroked the stones and spoke in tongues and splashed against my face,
    Till ages rolled, the sun shone cold on this unholy place.

    That was the planet Mars as channeled by the folk singer and science writer Jonathan Eberhart in Lament for a Red Planet.

    m
    Planet Mars

    Ever since the Italian astronomer Giovanni Schiaparelli thought he spied lines that he called “canali” on Mars in 1877, earthlings’ romantic thoughts about our nearest cosmic neighbor have revolved around water and its possible consequence, Life as We Know It. We haven’t found life on Mars, but decades of robotic exploration have indeed strengthened astronomers’ convictions that rivers and perhaps even oceans once flowed on the red planet.

    Today Mars is an arid, frigid desert, suggesting that the mother of all climate changes happened there, about four billion years ago or so. The question that haunts planetary scientists is why? And could it happen here?

    NASA’s Curiosity rover has found evidence of lakes and streams on a warmer, wetter, habitable Mars.

    NASA Mars Curiosity Rover
    Curiosity

    “I think the short story is the atmosphere went away and the oceans froze but are still there, locked up in subsurface ice,” said Chris McKay, an astrobiologist and Mars expert at NASA’s Ames Research Center.

    In September a new spacecraft known as Maven, the Mars Atmosphere and Volatile Evolution mission swung into orbit around the planet. Its job is to get a longer answer to one part of the mysterious Martian climate change, namely where the planet’s atmosphere went.

    NASA Mars MAVEN
    MAVEN

    One idea is that it was sputtered away by radiation and particles from the sun, known as the solar wind. Maven was designed to test that theory by measuring how fast Mars is losing atmosphere today. The results could help scientists determine what the atmosphere was like four billion years ago, and just how warm and wet the planet was.

    “We’re going to get some suggestive answers,” said Bruce Jakosky, a University of Colorado professor and principal investigator for Maven.

    The results could resonate beyond Mars or even our solar system, shedding light on the fickle habitability of exoplanets. Alien astronomers looking at our solar system with a good telescope four billion years ago might have concluded that Mars was a likely habitat for life. Now look at it.

    “What we are learning about are planetary atmospheres in general,” said David Brain, a Colorado astronomer and Maven team member. “It’s really fascinating to think that the planet changed in such a large way.”

    Everybody agrees that Mars was once wetter, on the basis of two lines of evidence. The surface of the planet is crossed with features that resemble old river channels, like the tributaries and canyons that lead into Chryse Planitia, the Plain of Gold, an ancient crater 1,000 miles wide and a mile-and-a-half deep. And NASA’s rovers have found minerals characteristic of watery environments, formed four billion years ago.

    But answers on exactly how wet and warm Mars was — and for how long — depend on whom you talk to.

    According to one camp, Mars back then had a thick atmosphere with enough carbon dioxide, the greenhouse gas looming big in Earth’s future, to warm up the temperature and keep it there for the hundreds of millions of years it would have taken to carve the Martian river system. Others have suggested that phenomena like asteroid impacts or the tilting of Mars’s poles could have produced shorter periods of near-freezing temperatures. The impact that created the huge crater called the Hellas basin, for example, would have hurled vast amounts of vaporized rock into the sky — leading to decades or centuries of hot rain and flash floods, said Brian Toon of the University of Colorado. It might have been followed perhaps by a lingering era of nearly freezing temperatures as clouds left over from the steam bath produced a mild greenhouse effect.

    Some geologists question whether the complicated river systems on Mars could have been created in such relatively short episodes, but they admit a serious flaw in their alternative view of a long-lasting greenhouse atmosphere of carbon dioxide. Namely, where did it go?

    “The holy grail of Mars,” said Dr. Jakosky of the Maven team, is to find the carbonate deposits that should have formed from its atmosphere. “We haven’t found them,” he said.

    Which is where the new Maven mission comes in. One of the most striking clues that something has happened on Mars has come from atmospheric measurements from previous probes. They have shown that the lighter forms, or isotopes, of elements like hydrogen, nitrogen and argon are strangely depleted by contrast with their abundance on Earth.

    On Mars the ratio of heavy nitrogen, which has an extra neutron in its nucleus, to regular nitrogen is twice that of Earth. The same pattern goes for argon, which is Dr. Jakosky’s favorite because it is chemically inert and can’t disappear from the inventory except by being swept out of the atmosphere.

    All told, Dr. Jakosky said, the isotopic ratios on Mars suggest that about 60 to 90 percent of the atoms that were once in the Martian atmosphere might have been lost to space.

    “We know the mechanism by which it was lost, but we can’t quantify it yet,” he said.

    The story goes something like this. Once upon a time, Mars had a magnetic field that, like Earth’s, acted as an umbrella, deflecting the rain of energetic particles shed by the sun. Earth’s field is generated by a dynamo, which in turn is powered by rising heat, convection in the planet’s molten iron core. Once Mars cooled off, the dynamo and the magnetic field stopped and the solar wind began pecking away at Mars’s atmosphere. Ultraviolet radiation from the sun would ionize atoms in the upper atmosphere, making them subject to forces from magnetic fields carried along in the solar wind, and they would slip away into space an atom or two at a time.

    “A little bit every few hours,” Dr. Brain of Colorado said, and “suddenly you can change an entire planet.”

    Eventually — with no atmosphere, no rain and none of the tectonic churning that keeps Earth’s oceans refreshed — the Martian rivers and oceans, if any, would have been absorbed into the ground and frozen, said James Kasting, a geoscientist at Penn State. Indeed, orbiting spectrometers have detected the signature of water in the form of ice under the wasted and lonely red sands.

    In September, after a 10-month trip from Earth and just in time to observe the effects of Comet Siding Spring pass by Mars, Maven began settling into a looping orbit around Mars, flying as close as 77 miles. Its instruments will observe the sun and solar wind; Mars’s upper atmosphere, the pool from which escaping particles are drawn; and the particles themselves as they escape. By understanding how the atmosphere is reacting to the sun today, Dr. Jakosky said, scientists should be able to extrapolate and say how much of the Martian atmosphere has been removed to space over the eons.

    If the amount lost is substantial — “a couple of bars of CO2,” he said, describing it in units of the atmospheric pressure on Earth — “would tell us that Mars must have been warmer in the past.”

    If losses are trivial, he said, that would spell death for the early greenhouse theory, and the great Martian arguments would continue.

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  • richardmitnick 9:44 am on December 12, 2014 Permalink | Reply
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    From NYT: “An Evolutionary Battle Against Bacteria” 

    New York Times

    The New York Times

    DEC. 11, 2014
    Carl Zimmer

    Every disease has a history. Some of that history is written in books, and some is written in our DNA.

    The earliest records of meningitis — an infection of the membranes that line the brain — reach back to 1685. The British physician Thomas Willis described fevered patients, some of whom suffered from “continual raving” and others who suffered from “horrible stiff extensions in the whole body.”

    But meningitis was a threat long before Willis put quill to paper. In a new study, published Thursday in the journal Science, two University of Utah scientists have uncovered a 40-million-year struggle between our ancestors and the bacteria that cause meningitis: As our ancestors evolved new defenses, our enemies evolve counter-defenses. By understanding the history of this struggle, we may be able to fight meningitis more effectively in the future.

    A number of species of bacteria can cause meningitis, but two — Haemophilus influenzae and Neisseria meningitidis — are the top threats. Like all bacteria, these pathogens need iron to grow. But we don’t make it easy for them to find iron inside our bodies.

    h
    Haemophilus influenzae

    m
    Neisseria meningitidis

    To move iron atoms from one cell to another, we seal them inside a kind of molecular lockbox, called transferrin. A cell can load two iron atoms into a single transferrin molecule and deliver it to another cell, which draws the transferrin inside and then opens it.

    t
    transferrin

    Transferrin lets us starve bacteria by making free iron atoms scarce. Simply withholding it from the bacteria “becomes an immune strategy,” said Nels C. Elde, an evolutionary geneticist and an author of the new study.

    A few years ago, Dr. Elde became puzzled by transferrin. Studies by other scientists suggested that it had experienced strong natural selection, changing its molecular structure over generations. But transferrin still does the same job it has been doing for hundreds of millions of years. It ferries iron atoms inside mammals, reptiles, amphibians and even fish.

    To understand what has driven transferrin’s evolution, Dr. Elde teamed with Matthew F. Barber, a postdoctoral researcher in his lab. They carried out an unprecedented study on the evolution of the gene that encodes transferrin, comparing our own version to those in 20 species of apes and monkeys.

    The two scientists confirmed that over the past 40 million years, our transferrin protein had undergone drastic changes. Transferrin is made up of two lobes, each of which grabs an iron atom. By far the most changes had occurred in only one of the lobes. The other one barely evolved.

    This finding gave Dr. Elde a clue as to what was driving the evolution of transferrin: meningitis-causing bacteria.

    Neisseria and Haemophilus can both steal iron from transferrin. They do so with a protein, TbpA, that pries open one of transferrin’s two lobes, exposing the iron atom inside. The lobe under attack is the one that has been evolving swiftly; the unmolested lobe has barely changed.

    t
    TbpA

    As the two Utah scientists were studying these evolutionary changes, researchers at the National Institutes of Health published the molecular details of how TbpA grabs transferrin. When Dr. Barber and Dr. Elde compared their results with the molecular structure, they were shocked. Almost every point at which transferrin made contact with TbpA has evolved, while little has changed beyond them.

    “That was the moment it all snapped together,” said Dr. Elde.

    Dr. Barber and Dr. Elde were able to reconstruct the history of transferrin. Each time its shape changed, it became harder for the bacteria to grab it and steal its iron.

    The scientists wondered if the bacteria had evolved in response to these changes. To find out, they got strains of Haemophilus influenzae and Neisseria meningitis from patients. They looked at the bacteria’s TbpA genes to see where they had evolved new structures.

    It turns out they changed where they made contact with transferrin. “It’s basically a mirror image,” said Dr. Elde.

    He and Dr. Barber argue that our ancestors and meningitis-causing bacteria have been locked in an arms race for 40 million years. Each time we make it harder for the bacteria to steal our iron, the bacteria change their structure to get a better grip on our transferrin.

    The race isn’t over. A new variant of transferrin has evolved in humans, and it is found in 6 to 25 percent of people, depending on their ethnic group. The Utah scientists found that Haemophilus influenzae bacteria can’t steal iron from the new variant. “It’s basically invisible,” Dr. Elde said.

    Harmit S. Malik, an evolutionary geneticist at the Fred Hutchinson Cancer Research Center who was not involved in the research, said that until he saw it, he doubted there were enough clues left in living primates to reconstruct the evolutionary arms race.

    But Dr. Barber and Dr. Elde proved him wrong. “It’s an extremely crisp result,” Dr. Malik said, adding, “Frankly, I didn’t think this could be done.”

    Despite all the defenses our ancestors evolved against these bacteria, they still pose a major threat to humanity. Haemophilus influenzae alone has been estimated to kill 371,000 people a year. Some researchers have investigated treating such infections by giving patients extra transferrin to starve bacteria.

    Dr. Malik suggested that this treatment would be even more effective if scientists used the evolutionary history of transferrin as a guide for designing transferrin that the bacteria can’t attack.

    “I suspect it could be a very, very important therapeutic,” he said. If he is right, our monkeylike ancestors could have a hand in saving the lives of our descendants.

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  • richardmitnick 8:46 am on December 11, 2014 Permalink | Reply
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    From NYT: “With Compromises, a Global Accord to Fight Climate Change Is in Sight” 

    New York Times

    The New York Times

    DEC. 9, 2014
    CORAL DAVENPORT

    LIMA, Peru — Diplomats from 196 countries are closing in on the framework of a potentially historic deal that would for the first time commit every nation in the world to cutting its planet-warming fossil fuel emissions — but would still not be enough to stop the early impacts of global warming.

    The draft, now circulating among negotiators at a global climate summit meeting here, represents a fundamental breakthrough in the impasse that has plagued the United Nations for two decades as it has tried to forge a new treaty to counter global warming.

    But the key to the political success of the draft — and its main shortcoming, negotiators concede — is that it does not bind nations to a single, global benchmark for emissions reductions.

    p
    A coal-burning power plant in Gelsenkirchen, Germany. Officials meeting in Peru are working on a pact to curb global warming. Credit Martin Meissner/Associated Press

    Instead, the draft puts forward lower, more achievable, policy goals. Under the terms of the draft, every country will publicly commit to enacting its own plans to reduce emissions — with governments choosing their own targets, guided by their domestic politics, rather than by the amounts that scientists say are necessary.

    The idea is to reach a global deal to be signed by world leaders in Paris next year, incorporating 196 separate emissions pledges.

    “It’s a breakthrough, because it gives meaning to the idea that every country will make cuts,” said Yvo de Boer, the former executive secretary of the United Nations Convention on Climate Change.

    “But the great hopes for the process are also gone,” he added. “Many people are resigned,” he said, to the likelihood that even a historic new deal would not reduce greenhouse gas levels enough to keep the planet’s atmospheric temperature from rising 3.6 degrees Fahrenheit.

    That is the point at which, scientists say, it will become impossible to avoid the dangerous and costly early effects of climate change — such as melting glaciers, rising sea levels, extreme drought, food shortages and more violent storms.

    The Lima draft represents the input of all the negotiating countries, though there are still several major hurdles to work out. But even then, experts say, at best the new deal might be enough only to curb global warming by about half as much as scientists say is necessary.

    Until recently, the United States and China, the world’s two largest greenhouse gas polluters, have been at the center of the impasse over a climate deal.

    Until this year, the United States had never arrived at the United Nations’ annual climate negotiations with a domestic policy to cut its own carbon emissions. Instead, it merely demanded that other nations cut their use of coal and gasoline, while promising that it would do so in the future.

    China, meanwhile, was the lead voice among nations demanding that developing economies should not be required to commit to any cuts.

    But in November, President Obama and President Xi Jinping of China announced plans to reduce emissions, helping inject new life into the global climate talks.

    Negotiators here call the joint announcement between China and the United States the catalyst for the new draft, which, if approved at the climate summit meeting this week, would set the stage for a final deal to be signed by world leaders next year in Paris.

    In the United Nations’ first effort to enact a climate change treaty, the 1997 Kyoto Protocol, the legally binding language of the agreement prescribed that the world’s largest economies make ambitious, specific emissions cuts — but it exempted developing nations. The United States Senate refused to ratify the treaty, effectively leaving it a failure.

    The Lima draft does not include Kyoto-style, top-down mandates that countries cut emissions by specific levels. Instead, it includes provisions requiring that all nations, rich and poor, commit to policies to mitigate their emissions. Countries that sign on to the deal will commit to announcing, by March, detailed, hard-numbers plans laying out how they will cut emissions after 2020.

    The draft that emerges this week “will look like a game of Mad Libs,” said one negotiator who was not authorized to speak publicly. Over the coming months, as countries put forth their emissions reduction pledges, the details of the final deal will be filled in.

    It is expected that many countries will miss that March deadline. Officials from India and other countries have said that they are unlikely to present a plan before June.

    In order to ensure that all countries are included in the deal, late announcers will get a pass. The point, United Nations officials say, is to ensure that the information exists to finalize a Paris deal by December 2015.

    Negotiators concede that the “each according to their abilities” approach is less than perfect — but that it represents what is achievable.

    “The reality of it is that nobody was able to come up with a different way of going about it that would actually get countries to participate and be in the agreement,” said Todd D. Stern, the lead American climate change negotiator. “You could write a paper, in theory, assigning a certain amount of emissions cuts to every country. That would get the reduction you need. But you wouldn’t get an agreement. We live in the real world. It’s not going to be perfect.”

    And there are still many hurdles ahead.

    While many major developing economies are now expected to follow China’s lead in preparing emissions plans, some countries remain wild cards. This year, the government of Australia repealed a landmark climate change law that taxed carbon pollution. Since then, its emissions have soared.

    “Australia is left without any viable policy to cut emissions,” said Senator Christine Milne, the leader of the Australian opposition Green Party. “It’s going to drag its heels.”

    Money, as always, is a sticking point.

    The increasing likelihood that the planet’s atmosphere will warm past the 3.6 degree threshold, with or without a deal in Paris, is driving demands by vulnerable nations — particularly island states and African countries — that the industrialized world open up its wallet to pay for the damage incurred by its fossil fuel consumption. Under the terms of a 2009 climate change accord reached in Copenhagen, rich countries have agreed to mobilize $100 billion annually by 2020 to help poor countries adapt to the ravages of climate change. But a report this month by the United Nations Environmental Program estimates that the cost to poor countries of adapting to climate change could rise to as high as $300 billion annually — and vulnerable countries are stepping up their demands that more money be included in any final deal. Many vulnerable and developing countries insist that each country’s national pledge include not just a plan to cut emissions, but also money for adaptation.

    “The financing question will be one of the deepest divides,” said Jennifer Morgan, an expert in climate change negotiations with the World Resources Institute, a research organization.

    Another element to be hashed out by negotiators will be devising an international number-crunching system to monitor, verify and compare countries’ pledged emissions cuts.

    China has always balked at any outside monitoring of its major economic sectors, and is pushing back on proposals for rigorous outside scrutiny.

    Hong Lei, a spokesman for the Chinese Ministry of Foreign Affairs, said that his country “always supports increasing transparency” but that the new reporting system should reflect “the reality that developing countries’ basic capacities in areas like national statistics and assessment are still insufficient.” He added that “developed countries should provide appropriate support to developing countries.”

    The United States has urged that a final deal not take the form of a legally binding treaty requiring Senate ratification, hoping to avoid a repeat of the 1997 Kyoto Protocol experience.

    But many countries continue to press for a legally binding deal.

    French officials have already given the yet-to-be-signed deal a working title: the “Paris Alliance.”

    The name, they say, is meant to signify that many different economies are working together, rather than complying with a single, top-down mandate.

    Edward Wong contributed reporting from Beijing.

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  • richardmitnick 8:32 am on December 11, 2014 Permalink | Reply
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    From NYT: “Study Gauges Plastic Levels in Oceans” 

    New York Times

    The New York Times

    DEC. 10, 2014
    JOHN SCHWARTZ

    It is no secret that the world’s oceans are swimming with plastic debris — the first floating masses of trash were discovered in the 1990s. But researchers are starting to get a better sense of the size and scope of the problem.

    A study published Wednesday in the journal PLOS One estimated that 5.25 trillion pieces of plastic, large and small, weighing 269,000 tons, could be found throughout the world’s oceans, even in the most remote reaches.

    p
    Plastic debris washed up on a beach in Azores, Portugal. Credit Marcus Eriksen

    The ships conducting the research traveled the seas collecting small bits of plastic with nets and estimated worldwide figures from their samples using computer models. The largest source of plastic by weight comes from discarded fishing nets and buoys, said Marcus Eriksen, the leader of the effort and co-founder of the 5 Gyres Institute, a nonprofit group that combines scientific research with antipollution activism.

    Dr. Eriksen suggested that an international program that paid fishing vessels for reclaimed nets could help address that issue. But that would do nothing to solve the problem of bottles, toothbrushes, bags, toys and other debris that float across the seas and gather at “gyres” where currents converge. The pieces of garbage collide against one another because of the currents and wave action, and sunlight makes them brittle, turning these floating junkyards into “shredders,” he said, producing smaller and smaller bits of plastic that spread far and wide.

    When the survey teams looked for plastics floating in the water that were the size of grains of sand, however, they were surprised to find far fewer samples than expected — one-hundredth as many particles as their models predicted. That, Dr. Eriksen said, suggests that the smaller bits may be swept deeper into the sea or consumed by marine organisms.

    The result echoed that of a paper published this year in Proceedings of the National Academy of Sciences that found a surprisingly low amount of small plastic debris. Those researchers estimated as much as 35,000 tons of the smaller debris were spread across the world’s oceans, but they had expected to find millions of tons.

    Andrés Cózar, a researcher from the University of Cadiz who headed that study, said in an email that he and Dr. Eriksen came to different conclusions about the amount of plastic afloat, but that “it is evident that there is too much plastic in the ocean,” adding, “The current model of management of plastic materials is (economically and ecologically) unsustainable.”

    The fact that the small plastics are disappearing is hardly good news. In fact, it could be far more troubling than the unsightly mess the plastics cause. Plastics attract and become coated with toxic substances like PCBs and other pollutants. Researchers are concerned that fish and other organisms that consume the plastics could reabsorb the toxic substances and pass them along to other predators when they are eaten.

    “Plastics are like a cocktail of contaminants floating around in the aquatic habitat,” said Chelsea M. Rochman, a marine ecologist at the University of California, Davis. “These contaminants may be magnifying up the food chain.”

    The ocean studies make an important contribution to the understanding of the floating waste problem, said Nancy Wallace, director of the marine debris program for the National Oceanic and Atmospheric Administration.

    Further research should look beyond the surface to test where the smaller plastic bits might have gone: into the deeper ocean depths, along the shoreline or settled on the seafloor. “It’s premature to say there is less plastic in the ocean than we thought,” she said. “There may just be less where we’re looking.”

    Dr. Eriksen said the scope of the problem makes floating garbage collection impractical. His group has had some success with campaigns to get manufacturers of health and beauty aids to stop using small scrubbing beads of plastic in their products.

    Manufacturers of other products, he said, must be urged to change their practices as well. “We’ve got to put some onus on producers,” he said. “If you make it, take it back, or make sure the ocean can deal with it in an environmentally harmless way.”

    Dr. Wallace agreed. “Unless we can stop the flow — turn off the tap of these pieces of debris going into the ocean all the time — we’re not going to be able to stop the problem.”

    The American Chemistry Council, which speaks for the plastics industries, issued a statement saying that its members “wholeheartedly agree that littered plastics of any kind do not belong in the marine environment,” and it cited industry efforts to combat the problem, including the 2011 Declaration of the Global Plastics Associations for Solutions on Marine Litter, which has led to 185 projects around the world.

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  • richardmitnick 10:37 am on December 9, 2014 Permalink | Reply
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    From NYT: “A One-Way Trip to Mars? Many Would Sign Up” 

    New York Times

    The New York Times

    DEC. 8, 2014
    NATALIE ANGIER

    When Seth Shostak, an astronomer who scans the cosmos for signs of extraterrestrial intelligence, asks middle school students how many of them want to go to Mars, all hands shoot up. When he asks how many would rather design robots that go to Mars, most hands drop back to their desks.

    SETI Seth Shostak
    Dr. Seth Shostak, SETI Institute

    And when he asks general audiences how many would go to Mars even if it meant dying a few weeks after arriving, he invariably finds volunteers in the crowd. “I kid you not,” said Dr. Shostak, the director of the Center for SETI Research. “People are willing to risk everything just to see Mars, to walk on the surface of our little ruddy buddy.”

    His experience accords with what many say is a distinct surge in public enthusiasm for space travel generally, and a manned mission to Mars in particular. Or make that a human mission: Women, too, are wholly on board. “I would totally love to go to Mars,” said Pamela A. Melroy, a former NASA astronaut who piloted two space shuttle missions and commanded a third.

    “We’ll get there,” she added. “I feel very strongly that we will.”

    But the questions of when and who the “we” will be remain very much up in the air. A “global exploration road map” prepared by NASA and 15 other space agencies envisions a presumably international team of astronauts bouncing over the frigid rouge dustscape of Mars by the 2030s. Private companies like SpaceX and Virgin Galactic say they may get there first, or better, or more democratically. Among the bolder if farther-fetched plans comes from a Dutch nonprofit venture called Mars One, which insists it will land four people on Mars — two men and two women — by 2025. As the project leaders see it, the technology needed to reach and colonize the red planet already exists, so why not go ahead and start loading the moving van?

    There is a catch, they say. Where NASA-style flight plans are designed on the Apollo moonshot model of round-trip tickets, the “one” in Mars One means, starkly, one way. To make the project feasible and affordable, the founders say, there can be no coming back to Earth. Would-be Mars pilgrims must count on living, and dying, some 140 million miles from the splendid blue marble that all humans before them called home.

    Nevertheless, enthusiasm for the Mars One scheme has been of middle-school proportions. Last year, the outfit announced that it was seeking potential colonists and that anybody over age 18 could apply, advanced degrees or no. Among the few stipulations: Candidates must be between 5-foot-2 and 6-foot-2, have a ready sense of humor and be “Olympians of tolerance.” More than 200,000 people from dozens of countries applied. Mars One managers have since whittled the pool to some 660 semifinalists.

    k
    Kellie Gerardi is also in the running to go to Mars. Credit Chang W. Lee/The New York Times

    Many space experts and Mars aficionados remain deeply skeptical about the program’s odds of success. They point out that Mars One doesn’t build rockets or any other aeronautic equipment, as SpaceX does. Nor does it have the tycoon portfolio of Virgin’s Sir Richard Branson. “I don’t take Mars One seriously at all,” said Andy Weir, author of The Martian,” a novel about a stranded astronaut struggling to survive on Mars that is so revered by engineers and techno-space geeks that it has been called “competence porn.”

    “I think they honestly believe in what they’re doing,” he added, “but I don’t think they have any chance of accomplishing it.”

    Others have complained that the group’s emphasis on the colonist selection process over financial or technical details of the mission is little more than a publicity stunt. Karen Cumming, 52, a Canadian journalist and teacher who is among the Mars One semifinalists, said she recently met the Canadian astronaut Chris Hadfield, who won fame on the International Space Station by singing David Bowie songs and showing the world how water behaves in low gravity.

    “I told him who I was, and I asked if he had any advice,” Ms. Cumming said. “He said: ‘Be relentless in your questioning about the hardware. Astronaut selection is the least of their worries.’ ”Bas Lansdorp, 37, who conceived of Mars One as an engineering student at the University of Twente in the Netherlands, admitted that its founders sought publicity, but said nobody paid attention when they announced last year that they had formed a partnership with Lockheed Martin.

    Choosing the right people for the expedition, he said, is not the least of their worries, but ultimately the only worry. The mission’s success or failure hinges on assembling a team of people who can live together in extreme circumstances, he said, “without losing their minds.”

    The various reasons offered for sending humans to Mars, at a cost of billions if not hundreds of billions of dollars — “but less expensive than the war in Iraq!” insisted Andrew Rader, a Mars One candidate and expert in human spaceflight with a doctorate from M.I.T. — include elements both practical and profound, optimistic and dystopian. Ellen Stofan, NASA’s chief scientist, said that for all the success of robots like Curiosity, sending humans to the surface “may be the only way to prove life evolved on Mars and what the nature of it is.” And demonstrating that some form of life arose at least twice in our solar system would lend ballast to the argument that the universe teems with life. Humans will soon need more space and more resources than Earth can offer, Dr. Shostak said, adding, “If you want to have Homo sapiens for the long run, you have to move out somewhere.” Whatever hardships the Mars homesteaders endure, Mr. Lansdorp argued, may well improve life for those back on Earth. “We’re a species that explores and pushes boundaries,” he said. “By exploring our own planet, we’ve developed technology to make our life more comfortable. Mars is the next logical step, the boundary to push, to make us more developed still.”

    Scientists agree that of all the places in the solar system where a few expatriate earthlings might settle, Mars is the least hostile. It’s roughly one-sixth the size of Earth, but given its lack of oceans, it nearly matches us in landmass. It rotates on an Earthlike tilt of 24 degrees and so has seasons, the length of its day is similar to ours, and its soil is about 2 percent frozen water, which in theory could be melted out and put to use. Its gravity is about 40 percent that of Earth — enough to keep inhabitants from the severe bone and muscle loss caused by long-term stints in outer space, but still of sufficient levity, said Norbert Kraft, chief medical officer for Mars One, “that maybe your knees won’t hurt and your wrinkles will go away.”
    Continue reading the main story Continue reading the main story
    Continue reading the main story

    Yet Mars remains a forbidding, frigid place, with an average temperature of minus 50 degrees Fahrenheit and an unbreathable atmosphere just 1 percent the density of Earth’s and consisting largely of carbon dioxide. Colonists would live in artificial podlike habitats, grow vegetables in greenhouses and get their protein from insects. No pets, sorry. And if you plan on going outside — as you will, often, to repair infrastructure battered by the chronic Martian wind, or to wipe off solar panels encrusted with the ubiquitous Martian dust — you must wear your spacesuit at all times.
    Photo

    j
    At 64, Jan Millsapps, holding an artist’s rendition of the Martian landscape, is among the older candidates on the Mars One list. Credit Thor Swift for The New York Times

    “No more smell of fresh grass, or the ocean,” Ms. Melroy said. “Giving that up would be a huge deal.” Another sacrifice, said Stephan Guenther, 46, a flight instructor and software developer in Cologne, Germany, and a Mars One semifinalist, would be the sound of silence. “There will always be some sound in the background, because the life support systems have to run,” he said. “If there’s real silence on Mars, something is going very badly.”

    Yet oh, how he wants to go to Mars. “I was not yet 1 year old when Neil Armstrong landed on the moon,” he said. “I was standing on the couch watching it on TV, and my mother wasn’t able to pull me away.” All he ever wanted to do in life was fly and go to space. “I had my pilot’s license before my driver’s license,” he said. At 64, Jan Millsapps, a professor of cinema at San Francisco State University, is among the older candidates on the Mars One list. “I’m at a point in my life where I’m ready for a new adventure,” she said. “I don’t feel like I’m running away. It’s more like I’m running toward.”

    Kellie Gerardi, 26, who works in the commercial spaceflight industry, says that even if Mars One never gets off the ground, it has already succeeded, elevating “the conversation about the need for space settlements to a global scale.”

    Ms. Gerardi is planning to get married in September, and a NASA astronaut is to officiate at the ceremony. Yet she would be willing to leave her husband behind should a Mars passport bear her name.

    Why doesn’t he apply to the program, too? For one thing, she said, “he doesn’t think it would be fun.” For another, he’s an inch too tall.

    See the full article here.

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  • richardmitnick 9:51 am on December 9, 2014 Permalink | Reply
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    From NYT: “Curiosity Rover’s Quest for Clues on Mars” 

    New York Times

    The New York Times

    DEC. 8, 2014
    KENNETH CHANG

    More than 3.5 billion years ago, a meteor slammed into Mars near its equator, carving a 96-mile depression now known as Gale Crater.

    g
    Curiosity Cradled by Gale Crater
    NASA’s Curiosity rover landed in the Martian crater known as Gale Crater, which is approximately the size of Connecticut and Rhode Island combined. A green dot [?]shows where the rover landed, well within its targeted landing ellipse, outlined in blue.
    This oblique view of Gale, and Mount Sharp in the center, is derived from a combination of elevation and imaging data from three Mars orbiters. The view is looking toward the southeast. Mount Sharp rises about 3.4 miles (5.5 kilometers) above the floor of Gale Crater.
    The image combines elevation data from the High Resolution Stereo Camera on the European Space Agency’s Mars Express orbiter, image data from the Context Camera on NASA’s Mars Reconnaissance Orbiter, and color information from Viking Orbiter imagery. There is no vertical exaggeration in the image.
    Image credit: NASA/JPL-Caltech/ESA/DLR/FU Berlin/MSSS
    Date 13 August 2012
    Source http://www.nasa.gov/images/content/676519main_pia16058-full_full.jpg
    Author NASA/JPL-Caltech/ESA/DLR/FU Berlin/MSSS
    That was unremarkable. Back then, Mars, Earth and other bodies in the inner solar system were regularly pummeled by space rocks, leaving crater scars large and small.
    What was remarkable was what happened after the impact.

    m
    Some scientists think Gale Crater was once fully buried with sediment and that winds excavated most of it, leaving an 18,000-foot mountain in the middle. (The colors represent different elevations.) Credit European Space Agency

    Even though planetary scientists disagree on exactly what that was, they can clearly see the result: a mountain rising more than three miles from the floor of Gale.
    More remarkable still, the mountain is layer upon layer of sedimentary rock.
    The layered rock drew the attention of the scientists who chose Gale as the destination for NASA’s Curiosity rover, a mobile laboratory the size of a Mini Cooper.
    Now, more than two years after arriving on Mars, Curiosity is climbing the mountain.

    NASA Mars Curiosity Rover
    Curiosity

    ESA Mars Express Orbiter
    ESA/Mars Express

    NASA Viking
    NASA/Viking

    In sedimentary rock, each layer encases the geological conditions of the time it formed, each a page from the book of Mars’ history. As Curiosity traverses the layers, scientists working on the $2.5 billion mission hope to read the story of how young Mars, apparently once much warmer and wetter, turned dry and cold in what John P. Grotzinger, the project scientist, calls “the great desiccation event.”

    Dr. Grotzinger remembers the first time he heard about Gale. “I looked at it, and immediately I’m like, ‘This is a fantastic site,’ ” he said. “What’s that mountain in the middle?”

    am
    Aeolis Mons

    Officially, the name is Aeolis Mons, but mission scientists call it Mount Sharp in homage to Robert P. Sharp, a prominent geologist and Mars expert at the California Institute of Technology who died in 2004.

    On Earth, mountains rise out of volcanic eruptions or are pushed upward by plate tectonics, the collision of pieces of the planet’s crust.

    Mars lacks plate tectonics, and volcanoes do not spew out of sedimentary rock. So how did this 18,000-foot mountain form?

    In the late 1990s, NASA’s Mars Global Surveyor spacecraft was sending back images of the Martian surface far sharper than those from earlier missions, like Mariner and Viking.

    NASA Mars Global Surveyor
    NASA/Mars Global Surveyor

    Kenneth S. Edgett and Michael C. Malin of Malin Space Science Systems, the San Diego company that built Global Surveyor’s camera, saw fine layered deposits at many places on Mars, including Gale. In 2000, they offered the hypothesis that they were sedimentary, cemented into rock.

    Indeed, Dr. Edgett said, it appeared that Gale Crater had been fully buried with sediment and that later winds excavated most of it, leaving the mountain in the middle.

    Imagine carving out of an expanse as large as 1.5 Delawares — a mound as tall, from base to peak, as Mount McKinley in Alaska, the tallest mountain in North America at 20,237 feet.

    Dr. Edgett asserts that that is plausible on Mars. He points to other Martian craters of similar size that remain partly buried. “There are places where this did happen, so it’s not ridiculous to think this is what happened at Gale,” he said.

    Still, in 2007 Gale had been discarded from the list of potential landing sites for Curiosity, because observations from orbit did not show strong evidence for water-bearing minerals in the rocks. NASA’s Mars mantra for the past two decades has been “Follow the water,” because water is an essential ingredient for life.

    Dr. Grotzinger asked Ralph E. Milliken, then a postdoc in his research group at Caltech, to take a closer look at Gale. With data from an instrument on NASA’s Mars Reconnaissance Orbiter that can identify minerals in the rocks below, Dr. Milliken showed the presence of clays at the base of Mount Sharp as well as other minerals that most likely formed in the presence of water.

    “The fact we have this mountain, and it’s not all the same stuff — the mineralogy is changing from one layer to the next — that gives us the hope that maybe those minerals are recording the interaction of the water and the atmosphere and the rocks,” said Dr. Milliken, now a geologist at Brown.

    Were water conditions there becoming more acidic? Was there oxygen in the water? “That’s something we can assess with the rover on the ground,” Dr. Milliken said.

    Since its landing on Mars in August 2012, Curiosity took a detour to explore a section named http://en.wikipedia.org/wiki/Yellowknife_Bay,_Mars
    and discovered geological signs that Gale was once habitable, perhaps a freshwater lake.

    y
    Geologic feature of Yellowknife Bay informally known as Shaler. The outcrop displays prominent cross-bedding, a feature indicative of water flows

    After that, the rover drove to Mount Sharp, with only brief stops for science. To date, the rover, operated by NASA’s Jet Propulsion Laboratory in Pasadena, Calif., has driven more than six miles, taken more than 104,000 pictures and fired more than 188,000 shots from a laser instrument that vaporizes rock and dirt to identify what they are made of.

    In September, Curiosity drilled its first hole in an outcrop of Mount Sharp and identified the iron mineral hematite in a rock. That was the first confirmation on the ground for a Gale mineral that had been first identified from orbit.

    When Curiosity reaches rocks containing clays, which form in waters with a neutral pH, that will be the most promising place to look for organic molecules, the carbon compounds that could serve as the building blocks of life, particularly if the rover can maneuver into a spot shielded from radiation. (It does not have instruments that directly test for life, past or present.)

    The orbiter also detected magnesium sulfate salts, which Dr. Milliken described as possibly similar to Epsom salts.

    h
    A 1999 Hubble telescope image showing Mars at a distance of 54 million miles from Earth. Credit NASA

    NASA Hubble Telescope
    NASA/ESA Hubble

    That layer appears to be roughly as old as sulfates that NASA’s older Opportunity rover discovered on the other side of Mars. If Mount Sharp sulfates turn out to be the same, that could reflect global changes in the Martian climate. Or they could be different, suggesting broad regional variations in Martian conditions.

    NASA Mars Opportunity Rover
    Opportunity

    “We’re finally beginning the scientific exploration of Mount Sharp,” Dr. Milliken said. “That was the goal.”

    Along the way, Curiosity may also turn up clues to the origins of Mount Sharp. While Dr. Edgett thinks Gale Crater filled to the brim before winds excavated the mountain, others, like Edwin S. Kite, a postdoctoral researcher at Princeton who is moving to the University of Chicago as a professor, think the mountain formed as a mound, with winds blowing layers of sand together that then were cemented by transient water. “Can you build up a pile like that without necessarily filling up the whole bowl with water?” Dr. Kite said. “Perhaps just a little bit of snow melt as the pile grows up.”

    He said the layers of Mount Sharp dip outward at the edges, as in an accumulating mound; they are not flat, as would be expected if they were lake sediments subsequently eroded by wind.

    Dr. Grotzinger thinks that both could have happened: that Gale Crater partly filled, then emptied to form the lower half of Mount Sharp, and a different process formed the upper portion. A sharp divide between the upper and lower parts of the mountain is suggestive.

    On Monday, during a NASA telephone news conference, Dr. Grotzinger and other members of the science team described new data suggesting long-lived lakes in the crater. The deposits at Yellowknife Bay could have been part of an ancient lake filled by streams flowing from the crater rim. As Curiosity drove toward Mount Sharp, it appeared to be traveling down a stack of accumulated deltas — angled layers where river sediment emptied into a standing body of water — and yet it was heading uphill. That pattern could have occurred if the water level were rising over time, and Mount Sharp was not there yet.

    That does not mean Gale was continually filled with water, but it suggests repeated wet episodes. “We don’t imagine that this environment was a single lake that stood for millions of years,” Dr. Grotzinger said, “but rather a system of alluvial fans, deltas and lakes and dry deserts that alternated probably for millions if not tens of millions of years as a connected system.”

    Ashwin Vasavada, the deputy project scientist, said that to explain the episodes of a lake-filled Gale crater, “the climate system must have been loaded with water.”

    But answers will remain elusive. “We’re not going to solve this one with the rover,” Dr. Edgett said. “We’re not going to solve this one with our orbiter data. We’re going to be scratching our heads a hundred years from now. Unless we could send some people there.”

    As successful as the NASA Mars rovers have been, their work is limited and slow. Curiosity’s top speed is not quite a tenth of a mile per hour. What might be obvious at a glance to a human geologist, who can quickly crack open a rock to peer at the minerals inside, could take days or weeks of examination by Curiosity.

    “I’d like to think it would take only a few months,” Dr. Edgett said of solving Mount Sharp’s mysteries, “with a few people on the ground.”

    See the full article, with interactive features, here.

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  • richardmitnick 8:45 am on December 9, 2014 Permalink | Reply
    Tags: , , , , , New York Times   

    From NYT: 28 Months on Mars 

    New York Times

    The New York Times

    December 9, 2014
    By Mike Bostock, Shan Carter, Jonathan Corum and Jeremy White
    Sources: NASA; Jet Propulsion Laboratory; NASA’s Navigation and Ancillary Information Facility; Joe Knapp; U.S.G.S. Astrogeology Science Center. Images by NASA and J.P.L. Panoramas, animation and mountain rendering by The New York Times

    NASA’s Curiosity rover has explored Gale Crater for 833 Martian days, or Sols. And it has found evidence, written in red rocks and sand, of lakes and streams on a warmer, wetter, habitable Mars.

    NASA Mars Curiosity Rover
    Curiosity

    t
    Traces of a Crater Lake
    Gale Crater as it might have appeared several billion years ago. Snow on the crater’s rim fed rivers and deltas flowing into the lake. The moving water carried sediment and carved patterns in the sand of the lakebed, leaving traces in the rocks that Curiosity is now driving over. The water was not too salty or too acidic, and could have supported microbial life.

    l
    Precision Landing
    Sol 0·Aug. 6, 2012
    The Curiosity rover touches down after an intricate, seven-minute landing sequence. The first images returned from the martian surface show the rover’s shadow stretching toward the bright slopes of Mount Sharp.

    r
    Rolling Out
    Sol 16·Aug. 22, 2012
    After spending two weeks testing its instruments, Curiosity makes its first drive and leaves its rocket-scorched landing site.

    o
    A Scoop of Rocknest
    Sol 61·Oct. 7, 2012
    Curiosity’s arm scoops its first sample of Martian soil, leaving a dark mark in a dune named Rocknest.

    s
    Self Portrait at Rocknest
    Sol 84·Oct. 31, 2012
    The rover spends six weeks at the Rocknest dune, studying the composition of the crater’s wind blown sand.

    r
    Six Months in Yellowknife Bay
    Sols 124–299·Dec. 11, 2012–June 9, 2013
    Curiosity spent most of its first Earth year on Mars in a broad, shallow basin called Yellowknife Bay. The rover drilled holes and took samples of low-lying mudstone, which formed from ancient lake and stream sediment.

    w
    Drilling at John Klein
    Sol 168·Jan. 25, 2013
    The rover examines a patch of mudstone on the floor of Yellowknife Bay for a suitable spot to drill. Curiosity was the first rover to drill a hole in another planet and extract a sample. A suite of chemistry experiments in the rover analyze the rock, which formed billions of years ago from lake sediments.

    c
    Drilling at Cumberland
    Sol 279·May 19, 2013
    Curiosity’s extended arm drills a second hole in Yellowknife Bay, extracting samples from a flat mudstone site named Cumberland.

    e
    The Long Drive to Mount Sharp
    Sol 324·July 4, 2013
    Curiosity begins driving toward its destination at the base of Mount Sharp, after almost a full Earth year studying the terrain near the landing site.

    d
    Darwin
    Sol 392·Sept. 12, 2013
    The rover’s first waypoint on its long drive to Mount Sharp is an outcrop called Darwin, an exposed patch of the bedrock underlying Gale Crater. Curiosity briefly studies the rock for evidence of past flowing water.

    c
    Upgrade at Cooperstown
    Sol 442·Nov. 3, 2013
    Curiosity pauses at its second waypoint, a scarp named Cooperstown. The rover spends a week downloading, installing and unexpectedly troubleshooting a software update from Earth.

    d
    Crossing Dingo Gap
    Sol 538·Feb. 9, 2014
    Curiosity looks back after driving over an elegant crescent-shaped dune spanning a narrow valley pass.

    l
    Layered Sandstone at the Kimberley
    Sol 580·March 25, 2014
    Curiosity examines the Kimberley, a large outcrop of layered sandstone slabs tilted toward Mount Sharp. The outcrop supports the idea that layers of lake and stream sediment accumulated in Gale Crater over millions of years.

    w
    Self Portrait at Windjana
    Sol 613·April 27, 2014
    Curiosity takes a self portrait near the end of its two-month exploration of the Kimberley outcrop. The rover is looking down at Windjana, a sandstone slab it drilled into eight days later.

    d
    On Damaged Wheels
    Sol 679·July 4, 2014
    The rover’s aluminum wheels have been heavily torn by driving five miles across the rough terrain of Gale Crater. To limit further damage, the rover has tried choosing paths over softer ground and sometimes driving in reverse.

    r
    Retreat From Hidden Valley
    Sol 711·Aug. 6, 2014
    Curiosity ends its second Earth year on Mars with its wheels deep in soft sand. Mission planners had hoped to drive across the rippled sand of Hidden Valley to protect the rover’s battered wheels, but decide to back out and stick to harder ground.

    p
    Pahrump Hills
    Sol 752·Sept. 17, 2014
    Curiosity reaches the Pahrump Hills, a pale outcrop of rock that is part of the base of Mount Sharp. The dark rippled areas are windblown drifts of sand and dust covering the flat bright rocks of the Pahrump Hills outcrop.

    h
    Drilling Into the Mountain
    Sol 759·Sept. 24, 2014
    Curiosity drills a hole in the Pahrump Hills outcrop. This is the rover’s first chance to sample rock from the base of Mount Sharp. Previous drill sites were rocks from the plain surrounding the mountain.

    s
    Salt Crystals in Mojave
    Sol 809·Nov. 15, 2014
    Curiosity cleans red dust from a patch of Martian rock named Mojave, part of the Pahrump Hills outcrop. Scattered through the rock are rice-shaped crystals of salt, which likely formed when an ancient lake or stream dried out. The crystals hint at a cycle of dry and wet conditions in the distant past of Gale Crater.

    t
    This Week
    Sol 831·Dec. 7, 2014
    In its 11th week at Pahrump Hills, Curiosity is making a second loop around the pale stones of the outcrop, brushing dust from the most interesting rocks and looking for a suitable place to drill.

    p
    The Path Ahead
    Curiosity has driven six miles since leaving its landing site. Soon the rover will begin climbing Mount Sharp, picking its way through buttes striped with layers that record the geological history of Gale Crater and the changing Martian environment.

    See the full article, with animations, here.

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  • richardmitnick 7:01 am on December 2, 2014 Permalink | Reply
    Tags: , , , , , , , New York Times   

    From NYT: “New Images Refine View of Infant Universe” 

    New York Times

    The New York Times

    DEC. 1, 2014

    NYT Dennis Overbye
    Dennis Overbye

    In a throwback to another era in cosmic history, astronomers on Monday discussed the birth of the universe in a 15th-century palace, the Palazzo Costabili in Ferrara, Italy, where the amenities do not include Internet access.

    The subject of Planck 2014, as the meeting is called, is a new baby picture — and all of the accompanying vital statistics — of the universe when it was 380,000 years old and space was as hot as the surface of the sun. The portrait taker was the European Space Agency’s Planck satellite, which spent three years surveying a haze of microwave radiation left over from the last moments of the Big Bang with a bevy of sensitive radio receivers.

    Cosmic Background Radiation Planck
    CMB

    ESA Planck
    ESA/Planck

    The data will not be published until Dec. 22 in the journal Astronomy & Astrophysics, and the lack of Internet access frustrated astronomers who had planned on watching a webcast of the proceedings but found themselves relying on Twitter feeds instead.

    At least, they reported, the coffee was suitably strong.

    The new data largely confirms and refines the picture from a temperature map of the microwaves that Planck scientists, a multinational collaboration led by Jan Tauber of the European Space Agency, produced in 2013, showing the faint irregularities from which gargantuan features like galaxies would grow. Its microwave portrait reveals a universe 13.8 billion years old that is precisely mysterious, composed of 4.9 percent atomic matter, 26.6 percent mysterious dark matter that is not atomic, and 68.5 percent of even more mysterious dark energy, the glib name for whatever it is that seems to be blowing the universe apart.

    new
    A map of a patch of sky showing the temperature and polarization of cosmic microwaves from the end of the Big Bang, as reflected by dust swirling in the magnetic field of the Milky Way. Credit European Space Agency

    The result is a resounding victory for a sort of Standard Model of Cosmology that has grown up over the last two decades, said Lyman Page, a Princeton astrophysicist, in a phone call from Ferrara. “What we see is pretty impressive,” he said. “It’s amazing that just six parameters describe the universe.”

    Standard Model of Cosmology Inflation Lambda Model
    Lambda-CDM model

    Standard Model of Cosmology
    Another view

    Cosmologists still do not know what dark matter — the material that provides the gravitational scaffolding for galaxies — is, but the Planck results have increased their knowledge of what it is not, according to the French Center for National Scientific Research.

    Recently space experiments like NASA’s Fermi Gamma-ray Space Telescope and Alpha Magnetic Spectrometer have recorded excess cosmic ray emissions that, some say, could be evidence of a certain kind of dark matter particles colliding and annihilating one another.

    NASA Fermi Telescope
    NASA/Fermi

    NASA AMS02 device
    NASA/AMS-02

    After Planck, we need another answer for those experiments, the French agency concluded in a statement.

    Neal Weiner, a particle theorist at New York University, who is not part of Planck, concurred. That model of dark matter, he said in an email, if not completely excluded, now could be severely constrained. “If this holds up, at the very least a possibility to discover dark matter is now diminished.”

    Planck dealt a blow to another possible dark matter candidate, namely a brand of the ghostly particles known as neutrinos. Physicists have known of three types of neutrinos for some time and have wondered if there were any more, whose accumulated mass would affect the evolution of the universe. Planck’s results leave little room for a fourth kind, so-called sterile neutrinos.

    Compounding the frustration of cosmologists in the room in Ferrara and at large was an issue that has galvanized them for the better part of a year: whether astronomers had detected the very beginnings of the Big Bang in the form of space-time ripples known as gravitational waves.

    Gravitational Wave Background
    Gravitational Waves per BICEP2 radio telescope.

    BICEP 2
    BICEP 2 interior
    BICEP 2 with South Pole Telescope

    The added value of the new Planck data is a map showing how the microwaves are polarized, information that could shed light on what was going on when the universe was a trillionth of a trillionth of a trillionth of a second old, and in the grip of forces about which physicists can only speculate.

    Among the hottest topics of speculation these days is the idea — known as inflation — that the universe underwent a violent and brief surge of expansion in the earliest moments, settling the geometry and other aspects of the present universe. Such an explosion, theorists say, would have left faint corkscrew swirls, known technically as B-modes, in the pattern of polarization of the microwaves.

    In March there was much excitement when a team of American astronomers operating a radio telescope at the South Pole called Bicep2 announced they had detected such a pattern. Alan Guth of M.I.T., one of the inventors(?) [theorist would be better] of inflation, was at the news conference at Harvard announcing the results.

    Alan Guth
    Alan Guth

    After three months of spirited debate, the astronomers conceded, however, that their signal could have been caused by interstellar dust, which can also twist the microwaves.

    Enter Planck, which observed the microwaves in nine different frequencies, making it easy to distinguish dust. Bicep2 had only one frequency.

    A preliminary report from Planck in September confirmed that there was enough dust in Bicep2’s patch of sky to account for the twisting, but there are still large uncertainties that leave room for primordial gravitational waves.

    Subsequently, Planck and Bicep agreed to pool their data for a joint analysis.

    Planck scientists have meanwhile published their own polarization maps, which astronomers say will be useful for studying how the anti-gravitational push of dark energy and the gravitational pull of dark matter orchestrated the growth of galaxies and the universe when it was two or three billion years old — a sensitive age.

    The bumps in the microwave maps that eventually grow to galaxies amount to a temperature difference of only about 75-millionths of a Kelvin, in an otherwise uniform hiss. To measure polarization, radio astronomers have to discern temperature differences about a tenth of that.

    The difficulty of doing this research, while the world looks on, can be gauged by the number of missed deadlines. Planck researchers originally hoped to have their polarization studies done this summer. Recently they had set November as their deadline, aiming to present the results at this conference in Ferrara. Likewise, the joint Bicep/Planck paper is now expected this month or in January.

    Asked about this, David Spergel, a Princeton cosmologist and veteran of cosmic microwave studies who had spent the day fielding Twitter messages from Ferrara, said he had adopted an acronym often used by NASA in announcing launch dates: NET, meaning “No Earlier Than.”

    See the full article here.

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  • richardmitnick 6:13 am on December 2, 2014 Permalink | Reply
    Tags: , , , , New York Times   

    From the NYT: “Avi Loeb Ponders the Early Universe, Nature and Life” 

    New York Times

    The New York Times

    DEC. 1, 2014
    Claudia Dreifus

    Much-Discussed Views That Go Way Back

    Among astrophysicists, Abraham Loeb is known for his creative and prolific attempts to understand the early universe.

    Dr. Loeb, known as Avi, specializes in 400,000 years to one billion years after the Big Bang. He has published more than 400 papers on the nature of early stars, galaxies, planets and black holes.

    al

    “Avi is very good at picking problems to work on that have testable results,” said Robert Wilson, who received the Nobel Prize in Physics (with Arno Penzias) for discovering cosmic microwave background radiation, thought to be a remnant of the Big Bang.

    I spoke with Dr. Loeb, 52, in his office here at Harvard, where he is the chairman of the astronomy department, and then later by telephone.

    Here is an edited and condensed version of our conversations.

    Q. WHY DID YOU CHOOSE THE EARLY UNIVERSE AS YOUR AREA OF STUDY?

    A. Because I like to work where there’s no crowd. One of the great pleasures of astrophysics is trying figure out something about the universe that nobody else has.

    When I first came to Harvard, about 20 years ago, I was attracted to the question of how and when did the first stars and galaxies form, because this was something that we really didn’t know much about. The only thing we knew was related to the cosmic microwave background radiation which originated about 400,000 years after the Big Bang.

    Cosmic Microwave Background  Planck
    CMB per ESA/Planck

    ESA Planck
    ESA/Planck

    We also knew that the galaxies and the stars didn’t always exist. So the question was, when did they form?

    Over the years, I’ve helped develop tools to image and map what happened. I’ve done calculations and suggested to observational astronomers ways to approach this era. I’ve developed a technique to image the universe in three dimensions that relates to the times when galaxies were formed, and I helped develop tests so that we can detect previously unknown galaxies and black holes. I also developed a test which will hopefully permit us to see the expansion of the universe in real time.

    It will be loaded onto the James Webb Space Telescope, which is scheduled to be launched in 2018. This should produce new insights. So this once lonely field has gotten crowded. It may be time to do other things.

    NASA Webb Telescope
    NASA/Webb

    LAST YEAR YOU PUBLISHED AN ASTONISHING PAPER SUGGESTING THAT SOME TYPE OF LIFE MIGHT HAVE BEEN POSSIBLE IN THE EARLY UNIVERSE, BILLIONS OF YEARS BEFORE IT APPEARED ON EARTH. WHERE DID THIS COME FROM?

    On Thanksgiving morning, I had this realization: that at the time the first stars and galaxies were formed, the cosmic microwave background — the radiation left over from the earliest time — was roughly at room temperature. So the universe, at roughly 15 million years after the Big Bang, was at a comfortable enough temperature for the chemistry of life to have incubated.

    I realized this while in the shower — as often happens. We had guests coming in the afternoon. So I asked my wife if instead of helping her with the meal, I could take care of the dishes after dinner. That gave me a few free hours to think this out.

    What it came down to was that if there had been planets that early, they could have been warmed by the cosmic microwave background. They didn’t need to be warmed by a star. And so the chemistry of life could have started that early.

    After I finished working this out, I posted a draft of my paper on arXiv.org, a server where astrophysicists upload writings for feedback from colleagues. To my surprise, journalists also looked at it. Immediately, the phone rang. The paper ended up receiving a lot of media attention.

    WHAT DO YOU MAKE OF THAT?

    People are interested. Historically, cosmology has described the universe as full of lifeless objects. That may be a misconception. It may be that the universe is teeming with life. The problem is that life does not produce a lot of energy and it’s hard to detect.

    I’ve been curious about how this limits us in the search for life. Suppose there is an extraterrestrial civilization on a planet near a star not far from us, and suppose there was a nuclear war there. Could we see it with our telescopes? Turns out that even with the most powerful of contemporary telescopes, we couldn’t see the flare.

    However, there are ideas and techniques for detecting more subtle signatures — for example, radio signals.

    YOU ONCE PUBLISHED A PAPER SUGGESTING THAT IF WE’RE SERIOUS ABOUT LOOKING FOR EXTRATERRESTRIAL LIFE, WE MIGHT SEEK OUT MARKERS OF INDUSTRIALIZATION, LIKE SMOG. SMOG?

    Yes, smog might serve as a fingerprint of an industrial civilization. It’s always been thought that the way to detect life elsewhere was to look for signs of oxygen. But intelligent life could produce unnatural molecules. They might do that intentionally if their planet was too cold for life. Unnatural molecules might even show signs of a civilization that may not exist anymore because unnatural molecules can survive long after a civilization.

    SOME OF YOUR WORK SOUNDS ALMOST LIKE SCIENCE FICTION. WHERE DO YOU DRAW THE LINE?

    It’s not that. Nature has richness beyond our imagination. What I look for are interesting astrophysics questions that are provable. Though my research may ask unconventional questions, the answers are based on calculations, experiments and observations.

    DID YOU ALWAYS WANT TO BE AN ASTROPHYSICIST?

    At a young age, I was attracted to philosophy because it asked the most interesting questions. But then, at 18, I had to do my military service in Israel, where I grew up. After some testing, I was allowed to join a special program where you could work on projects useful for the defense of the country. I ended up doing research in plasma physics. And because of that, I was able to visit the United States in the 1980s.

    During one of these trips, I visited the Institute for Advanced Study. A month later, I was offered the opportunity to do a postdoc there. There was one condition, though: I had to switch to astrophysics. That appealed because it was like returning to an old love — philosophy. In astrophysics, I could address very big questions about nature and life.

    IN YOUR STUDIES OF THE EARLY UNIVERSE, YOU RUN SMACK AGAINST THE IDEAS OF THE BOOK OF GENESIS. HOW DO YOU DEAL WITH THAT?

    The first chapter of the Bible states that there was a beginning in time. Science shows that we live in an expanding universe, and if you extrapolate, there was a point in time in when things began. In some ways, they are consistent.

    IS IT POSSIBLE FOR AN ASTROPHYSICIST TO BE RELIGIOUS?

    It really depends on what you mean by “God.” [Baruch] Spinoza would feel very comfortable with modern science because in his philosophy, God is nature. That pretty much summarizes [Albert] Einstein’s view, too. So if you’re defining God in a way that identifies the laws of nature with his or her qualities, that’s perfectly consistent. But if you attribute parts of reality to God in a way that cannot be understood by rational thinking, a conflict emerges.

    HOW DO YOU HANDLE THE VAST QUANTITIES OF TIME AND SPACE THAT YOU MUST NAVIGATE TO DO YOUR WORK? DO YOU, AS IN THAT OLD KURT WEILL SONG, EVER FEEL LOST IN THE STARS?

    Personally, I do not feel lost in the stars, but rather at home with all of them. When I look at the stars of the Milky Way on a clear night, they appear to me like the lights of a giant spaceship streaming through the universe.

    Are there any passengers around the other lights in this spaceship? It would be fun to know and perhaps, share experiences with them.

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

     
  • richardmitnick 10:11 am on November 29, 2014 Permalink | Reply
    Tags: , , , , , New York Times, Triton   

    From NYT: “A Captured Ice Moon | Out There | The New York Times “ 

    New York Times

    The New York Times

    temp
    Global Color Mosaic of Triton, taken by Voyager 2 in 1989

    NASA Voyager 2

    Neptune’s moon Triton was the last stop on Voyager 2’s tour of the outer planets. It is one of the coldest objects in the solar system and a big brother of Pluto, which NASA will visit next year.

    Produced by: Dennis Overbye, Jason Drakeford and Jonathan Corum

    Watch, enjoy learn.

    See the full article here.

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

     
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