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Nasa Curiosity rover tests suggest life may have existed on Mars

Technogin

Link to video: Curiosity rover finds drinkable water on Mars, says Nasa

An ancient network of rivers on Mars once made parts of the planet habitable for microbial life, according to the latest analysis from Nasa‘sCuriosity rover.

Rock dust drilled from sediments in the giant Gale crater on the red planet were found to contain clay minerals that can have formed only in water, scientists said.

The discovery of other substances alongside the clays, such as calcium phosphate, suggest the soil was neutral or mildly alkaline, making the environment suitable for microbes.

Instruments aboard the Curiosity rover have allowed scientists to build up a gradual picture of the planet’s geological past, but the latest analyses are the strongest evidence yet that Mars was once hospitable to life.

“A fundamental question for this mission is whether Mars could have supported a habitable environment,” Michael Meyer, a lead scientist…

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Glaciers Contribute Significant Iron to North Atlantic Ocean

Research area: During the course of two expeditions to the Greenland ice sheet in May and July 2008, Bhatia and her colleagues collected samples from sites at three land-terminating glaciers. The meltwater from these glaciers travels through a flood plain and eventually drains into Qasigiatsigit Lake, before finally emptying into the fjord. (courtesy Maya Bhatia, Woods Hole Oceanographic Institution)

Research area: During the course of two expeditions to the Greenland ice sheet in May and July 2008, Bhatia and her colleagues collected samples from sites at three land-terminating glaciers. The meltwater from these glaciers travels through a flood plain and eventually drains into Qasigiatsigit Lake, before finally emptying into the fjord. (courtesy Maya Bhatia, Woods Hole Oceanographic Institution)

All living organisms rely on iron as an essential nutrient. In the ocean, iron’s abundance or scarcity means all the difference as it fuels the growth of plankton, the base of the ocean’s food web.

A new study by biogeochemists and glaciologists at Woods Hole Oceanographic Institution (WHOI) identifies a unexpectedly large source of iron to the North Atlantic – meltwater from glaciers and ice sheets, which may stimulate plankton growth during spring and summer. This source is likely to increase as melting of the Greenland ice sheet escalates under a warming climate.

 

The study was published online in Nature Geoscience on March 10, 2013.

“There’s only been one other study looking at the amount of iron that’s being released in meltwater runoff itself,” says Maya Bhatia, a graduate of the MIT/WHOI Joint Program in Oceanography and Applied Ocean Sciences and Engineering, and the study’s lead author, “and that had reported high nanomolar concentrations. So to find iron in concentrations several orders of magnitude higher – in the micromolar range – was very surprising.”

Iron from wind-blown dust and river runoff fuels annual plankton blooms in the world’s ocean. Ice sheets and glaciers are now also thought to contribute iron from sediments on the bottom of calved icebergs and glacially-derived dust. Until now, meltwater runoff from glaciers and ice sheets was considered too dilute to carry much iron, although previous research has shown a strong correlation between the plankton blooms and the runoff from Greenland ice sheet.

“Glacial runoff has only recently been considered a potentially important source of nutrients that are useable, or bioavailable, to downstream ecosystems,” says Bhatia. “We believe our study now adds iron to that list of nutrients, and underscores the potential for a unique but as-yet-undetermined chemical impact from increasing ice sheet meltwater runoff.”

During the course of two expeditions to the Greenland ice sheet in May and July 2008, Bhatia and her colleagues collected samples from sites at several land-terminating glaciers on the western side of the Greenland ice sheet. The glaciers’ meltwater empties into a large lake, which eventually drains into an estuary system before reaching the open ocean. Their study reports levels of dissolved iron orders of magnitude higher than previously found for Greenland glacial runoff rivers.  When the WHOI team extrapolated their findings to calculate the contribution of iron from the entire ice sheet, they estimated its value to be within the range of that from dust deposition in the North Atlantic, which is believed to be the primary source of bioavailable iron to this ocean. This value is only an order of magnitude lower than the estimated annual contribution of iron from rivers worldwide.

When an ice sheet or glacier melts, most of the water doesn’t simply run off the surface of the ice sheet. Instead it first drains to the bedrock below the ice sheet through cracks and conduits called moulins and then exits in large runoff rivers.

“A lot of people think of a glacier and an ice sheet as a big block of ice,” says Bhatia, “but it’s actually quite a porous, complicated system underneath a glacier, with lots of moulins and crevasses leading to the bottom. Once you get into the bottom, there are large tunnels that these waters are passing through.” The more time the water spends in contact with the bedrock and sediments beneath the glacier, the more nutrients it picks up, including iron.

The WHOI team says further research is needed to determine how much of this iron actually reaches the open ocean, as their study followed the meltwater from the edge of the glaciers to the large lake they empty into. For this study, the team assumed that the amount of iron filtered out as the water moves through estuaries before reaching the marine environment would be roughly the same for glacial systems as it is for river systems.

The researchers hope to do more work to confirm the study’s numbers by sampling over a larger geographical area. Additional research could also confirm whether this influx of iron is in a form that can be easily utilized by phytoplankton and therefore stimulates primary production in the ocean.

“We don’t have enough historical measurements to say that this iron contribution is an increase over past conditions, but if it is working the way we think it is, the contribution would be greater as meltwater discharge increases,” Bhatia says. “It is interesting to think that, as ice sheets melt, there are biogeochemical considerations beyond changing sea level.”

Are we ready to meet ET?

Once only science fiction, astronomers are now finding hundreds of planetary systems beyond our own. Given recent discoveries through space exploration, it is entirely feasible that we may soon discover the existence of extra-terrestrial life (ET) forms on other planets.

The idea of extra-terrestrial life forms fascinates some and terrifies others. And even though our search for ET never quite panned out, we never stopped looking.

However, could this all be about to change following the discovery of hundreds of exoplanets (planets outside our Solar System), and thousands of candidate exoplanetary systems, some of which might be habitable for life.

 

Speaking about these momentous discoveries at the Cambridge Science Festival on March 16, NASA’s Dr Jennifer Wiseman will reveal how these exoplanets may provide evidence of biological activity, and discuss the profound invigoration of scientific and related religious and philosophical thought this might inspire if we find that life could thrive beyond Earth.

In a recent interview, Dr Wiseman said: “It’s a very exciting time for astronomy; we are finding a plethora of planets around other stars, including some that may be similar to Earth in size and temperature. The question that humans have had for centuries – whether or not there are planets similar to our own around other stars – seems more and more to be best answered as, ‘Yes!’”

It is expected that there is at least one planet, on average, orbiting around each star in our Milky Way galaxy, resulting in hundreds of billions of exoplanets, some fraction of which are the size of Earth at similar distances from their parent stars as Earth is to the Sun. These staggering numbers means there is a real possibility that we are on the verge of discovering our twin. If so, could this also mean the discovery of alien life forms similar to humans? And, what could this mean for humanity’s self-image if we were to discover that we are not unique or alone in the universe?

As Senior Project Scientist for NASA’s Hubble Space Telescope and Director of the Dialogue on Science, Ethics and Religion for the American Association for the Advancement of Science, Dr Wiseman is uniquely placed to provide both insights into the latest developments in the search for inhabitable exoplanets, as well as reflections on philosophical and religious implications of finding life on another planet.

From identifying seismic wave activity and colour patterns on these other worlds, to the use of enormous telescopes that could potentially hunt for evidence of alien life by their atmospheres, astronomers are continuing to find new ways to look for that tantalising hint of life.

In January this year, astronomers announced the discovery of an Earth-like exoplanet candidate orbiting a star similar to our Sun in the ‘habitable zone’ – the area around a star within which it is theoretically possible for water to exist on a planet’s surface (and therefore also the possibility of supporting life). And in February, Harvard researchers identified three planets as ‘objects of interest’ – meaning they could also be potentially habitable.

Harvard astronomer and lead author Courtney Dressing, who presented the findings at the Harvard-Smithsonian Center for Astrophysics, said: “We thought we would have to search vast distances to find an Earth-like planet. Now we realise another Earth is probably in our own backyard, waiting to be spotted.”

In addition, the World Economic Forum Global Risks report for 2013 states that, “Given the pace of space exploration, it is increasingly conceivable that we may discover the existence of alien life or other planets that could support human life. … In 10 years’ time, we may have evidence not only that Earth is not unique, but also that life exists elsewhere in the universe.”

The report continued, “The discovery of even simple life would fuel speculation about the existence of other intelligent beings and challenge many assumptions that underpin human philosophy and religion.”

Professor Meric Srokosz, Associate Director of The Faraday Institute for Science and Religion, Cambridge (the organisers of the event) said: “This is a unique opportunity to hear a genuine expert in her field, and to learn and think about one of the questions that continues to fascinate: is there life out there in the universe?”

Scientists make mouse model of human cancer, demonstrate cure

Scientists report the first successful blocking of tumor development in a genetic mouse model of an incurable human cancer.

“To my knowledge, this is the first time that a mouse model of a genetically defined malignant human cancer has been generated in which the formation of the tumor from beginning to end can be monitored and in which blocking the pathway cures the mouse of the tumor,” said Dr. Luis Parada, chair of the department of developmental biology at UT Southwestern and senior author of the study published in Cell and online. The study’s first author is Dr. Wei Mo, a postdoctoral researcher in the department.

 

“We showed that blocking the activity of a receptor molecule named CXCR4 in these tumors – through genetic manipulation or by chemical blockade – inhibited tumor development. Together, these data reveal a potential target for therapy of these uncommon but currently untreatable malignant peripheral nerve sheath tumors (MPNSTs),” Dr. Parada added.

The study is a collaboration between Dr. Parada’s laboratory and that of Dr. Lu Q. Le, co-senior author of the study and assistant professor of dermatology. Dr. Le also is co-director of the adult Comprehensive Neurofibromatosis Clinic at UT Southwestern, the first such clinic in North Texas, which is part of the Simmons Comprehensive Cancer Center. The researchers noted that co-authors at The University of Texas MD Anderson Cancer Center and Baylor College of Medicine, Houston, greatly accelerated the research effort.

MPNSTs are rare but highly aggressive tumors that are resistant to therapy and are typically fatal. The malignancies can occur sporadically or in a subset of patients with a condition called neurofibromatosis 1 (NF1) – one of the most commonly inherited disorders of the nervous system, which affects an estimated 1 in 3,500 people.

The severity of NF1 can vary widely, even among family members, from mild dermatological symptoms to benign tumors that wrap around nerves and can be disfiguring, debilitating, and even life-threatening, depending on where they form, Dr. Le said. In addition, individuals with an improperly-functioning NF1 gene have an increased risk of developing cancerous tumors such as MPNSTs, he said.

The researchers generated a mouse model that spontaneously develops MPNSTs and compared gene expression activity in cancerous tumors and in the precursor cells that give rise to the tumors, which are the kind of cells in which MPNSTs develop.

They found that a protein (CXCR4), which is essential for tumor growth, is more abundant in cancerous cells than in precursor cells. In addition, they found that a molecule produced by the cancer cells themselves (CXCL12) works with CXCR4 to further the growth of cancer by stimulating the expression of the cyclin D1 protein, which promotes cell division via a signaling pathway outlined in the study.

When they examined human MPNSTs, the scientists found increased expression of CXCR4 accompanied by activity in the same pathway as the one identified in the mice, the researchers said.

Next, they blocked the activity of CXCR4 in the MPNST mice using either genetic manipulation or an FDA-approved antagonist drug for CXCR4 called AMD3100. Both strategies inhibited cancer development in mice whose tumors expressed increased levels of CXCR4, and were less effective in tumors without increased CXCR4 expression. They identified the same situation in the human cancer cells, the researchers report.

“We are very encouraged by these findings because they provide us with new directions and therapeutic windows to combat this deadly cancer, where none exist today,” said Dr. Le, who added that the researchers are currently planning human trials.

Building a better battery

A new battery technology provides double the energy storage at lower cost than the batteries that are used in handheld electronics, electric vehicles, aerospace and defence.

The batteries used in these applications are typically based on lithium and a metal oxide, such as cobalt, manganese or nickel. Researchers from the University of Cambridge have developed a composite of sulphur and nanostructured carbon, for use as a battery cathode with much higher energy storage at much lower cost than conventional materials.

 

The cathode, or positive electrode, is one of three functional components of a battery, along with the anode (negative electrode) and electrolyte. The raw cathode materials are the single largest material cost in battery production, representing between 35 and 40 per cent of total costs.

The global lithium-ion battery market is expected to expand to $54 billion by 2020, up from $11.8 billion in 2010, driven primarily by demand from the consumer electronics and electric vehicle sectors.

“Using sulphur instead of the materials currently used in lithium-ion batteries could substantially reduce production costs, as sulphur is a fraction of the cost of other materials,” says Dr Can Zhang of the Department of Engineering, one of the developers of the material. “Additionally, compared with conventional lithium-ion batteries, the carbon-sulphur electrodes achieve double the energy density per unit of weight.”

The carbon-sulphur electrodes are produced by growing a “forest” of high-quality carbon nanotubes (CNTs) on a layer of metal foam. The CNT forest provides excellent electrical conductivity, and acts as a three-dimensional scaffold into which the sulphur is injected in order to form the cathode.

The sulphur is trapped within the scaffold in the form of small particles which store electrons. The pore structure of the metal foam, combined with the dense vertical packing of CNTs, provides a labyrinth with a large surface area for the retention of electrode material.

Despite their higher density and lower costs, the commercial development of lithium-sulphur batteries has been largely plagued by short cycle life, typically below 80 charge-discharge cycles. In comparison, a conventional lithium-ion battery will usually achieve 500 charge-discharge cycles. The CNT-sulphur composite significantly enhances the cycle performance of lithium-sulphur batteries, retaining 80% capacity after over 250 full charge-discharge cycles.

The work is the result of a collaboration between the groups of Professor John Robertson of the Department of Engineering and Dr Vasant Kumar of the Department of Materials Science and Metallurgy.

Dr Zhang, a postdoctoral researcher in Professor Robertson’s group, has formed CamBattery to commercialise the technology, along with PhD students Bingan Chen, Kai Xi and Wentao He. The company won Technology Start-up of the Year at the 2012 Cambridge University Entrepreneurs competition.

Over the next two years, the team intends to build the first roll-to-roll machine to continuously produce the cathode material, and sell the product to major battery manufacturers. While the number of charge-discharge cycles achieved by lithium-sulphur batteries is not yet high enough for CamBattery to enter the consumer electronics market, applications in aerospace and defence are strong possibilities. “For aerospace and defence applications, energy storage takes precedence over life cycle,” says Dr Zhang. “However, we will continue working at getting the number of life cycles high enough for consumer electronics and electric vehicles.”

The Cambridge University Entrepreneurs (CUE) Business Creation Competition is the UK’s biggest student business plan competition. Since its creation in 2000, the competition has had more than 1,000 entries and awarded £500,000 in prize money to students and staff. Companies from the competition have gone on to raise close to £70 million in further funding.

NASA Mission Helps Craft 3-D Image Of Buried Mars Flood Channels

This illustration schematically shows where the Shallow Radar instrument on NASA's Mars Reconnaissance Orbiter detected flood channels that had been buried by lava flows in the Elysium Planitia region of Mars. Marte Vallis consists of multiple perched channels formed around streamlined islands. These channels feed a deeper and wider main channel. In this illustration, the surface has been elevated, and scaled by a factor of one to 100 for clarity. The color scale represents the elevation of the buried channels relative to a Martian datum, or reference elevation. The reason the values are negative is because the elevation of the surface of Mars in this region is also a negative -- below average global elevation.  Credit: NASA/JPL-Caltech/Sapienza University of Rome/Smithsonian Institution/USGS

SIllustration  shows where the Shallow Radar instrument detected flood channels that had been buried by lava flows in the Elysium Planitia region of Mars.

NASA’s Mars Reconnaissance Orbiter (MRO) has provided images allowing scientists for the first time to create a 3-D reconstruction of ancient water channels below the Martian surface.

The spacecraft took numerous images during the past few years that showed channels attributed to catastrophic flooding in the last 500 million years. Mars during this period had been considered cold and dry. These channels are essential to understanding the extent to which recent hydrologic activity prevailed during such arid conditions. They also help scientists determine whether the floods could have induced episodes of climate change.  The estimated size of the flooding appears to be comparable to the ancient mega flood that created the Channeled Scablands in the Pacific Northwest region of the United States in eastern Washington.


The findings are reported in the March 7 issue of Science Express by a team of scientists from NASA, the Smithsonian Institution, and the Southwest Research Institute in Houston.

“Our findings show the scale of erosion that created the channels previously was underestimated and the channel depth was at least twice that of previous approximations,” said Gareth Morgan, a geologist at the National Air and Space Museum’s Center for Earth and Planetary Studies in Washington and lead author on the paper. “This work demonstrates the importance of orbital sounding radar in understanding how water has shaped the surface of Mars.”

The channels lie in Elysium Planitia, an expanse of plains along the Martian equator and the youngest volcanic region on the planet. Extensive volcanism throughout the last several hundred million years covered most of the surface of Elysium Planitia, and this buried evidence of Mars’ older geologic history, including the source and most of the length of the 620-mile-long (1000-kilometer-long) Marte Vallis channel system. To probe the length, width and depth of these underground channels, the researchers used MRO’s Shallow Radar (SHARAD).

Marte Vallis’ morphology is similar to more ancient channel systems on Mars, especially those of the Chryse basin. Many scientists think the Chryse channels likely were formed by the catastrophic release of ground water, although others suggest lava can produce many of the same features. In comparison, little is known about Marte Vallis.

With the SHARAD radar, the team was able to map the buried channels in three dimensions with enough detail to see evidence suggesting two different phases of channel formation. One phase etched a series of smaller branching, or “anastomosing,” channels that are now on a raised “bench” next to the main channel. These smaller channels flowed around four streamlined islands. A second phase carved the deep, wide channels.

“In this region, the radar picked up multiple ‘reflectors,’ which are surfaces or boundaries that reflect radio waves, so it was possible to see multiple layers, ” said Lynn Carter, the paper’s co-author from NASA’s Goddard Space Flight Center in Greenbelt, Md. “We have rarely seen that in SHARAD data outside of the polar ice regions of Mars.”

The mapping also provided sufficient information to establish the floods that carved the channels originated from a now-buried portion of the Cerberus Fossae fracture system. The water could have accumulated in an underground reservoir and been released by tectonic or volcanic activity.

“While the radar was probing thick layers of dry, solid rock, it provided us with unique information about the recent history of water in a key region of Mars,” said co-author Jeffrey Plaut of NASA’s Jet Propulsion Laboratory (JPL), Pasadena, Calif.

The Italian Space Agency provided the SHARAD instrument on MRO and Sapienza University of Rome leads its operations. JPL manages MRO for NASA’s Science Mission Directorate in Washington. Lockheed Martin Space Systems of Denver built the orbiter and supports its operations.

Aegis Ballistic Missile Defense System Scores Another Hit

This photo is pretty impressive. The story behind it is even more impressive. It shows the test of the U.S. Navy’s Aegis Ballistic Missile Defense System, the sea-based component of the Missile Defense Agency’s Ballistic Missile Defense System. So what happened during this joint MDA and Navy test?

 

  • At 11:10 p.m. HST last Tuesday, a medium-range ballistic missile target was launched from the Pacific Missile Range Facility, on Kauai, Hawaii.
  • The target flew northwest towards a broad ocean area of the Pacific Ocean.
  • The in-orbit Space Tracking and Surveillance System-Demonstrators detected and tracked the target.

Space Tracking and Surveillance System-Demonstrator (Source: Northrop Grumman)

Space Tracking and Surveillance System-Demonstrator (Source: Northrop Grumman)

  • It forwarded track data to USS Lake Erie (CG 70), which is equipped with the second-generation Aegis BMD weapon system, to engage the target with Launch on Remote doctrine.
  • The ship developed a fire control solution from the STSS-D track and launched the SM-3 Block IA guided missile approximately five minutes after the target launched.
  • The SM-3 intercepted the target and vaporized it following a direct-hit minutes after its launch.

This marked the first live-fire intercept of a medium-range ballistic missile using space-based sensors. It was the 24th successful intercept in 30 flight test attempts for the Aegis BMD program since flight testing began in 2002.