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NASA’s Europa Mission Begins With Selection Of Science Instruments


Bizarre features on Europa’s icy surface. Credits: NASA/JPL-Caltech

Bizarre features on Europa’s icy surface. Credits: NASA/JPL-Caltech

NASA has selected nine science instruments for a mission to Jupiter’s moon Europa, to investigate whether the mysterious icy moon could harbor conditions suitable for life.

NASA’s Galileo mission yielded strong evidence that Europa, about the size of Earth’s moon, has an ocean beneath a frozen crust of unknown thickness. If proven to exist, this global ocean could have more than twice as much water as Earth. With abundant salt water, a rocky sea floor, and the energy and chemistry provided by tidal heating, Europa could be the best place in the solar system to look for present day life beyond our home planet.

“Europa has tantalized us with its enigmatic icy surface and evidence of a vast ocean, following the amazing data from 11 flybys of the Galileo spacecraft over a decade ago and recent Hubble observations suggesting plumes of water shooting out from the moon,” said John Grunsfeld, associate administrator for NASA’s Science Mission Directorate in Washington. “We’re excited about the potential of this new mission and these instruments to unravel the mysteries of Europa in our quest to find evidence of life beyond Earth.”

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A Habitable Environment On Martian Volcano?


The slopes of a giant Martian volcano, once covered in glacial ice, may have been home to one of the most recent habitable environments yet found on the Red Planet, according to new research led by Brown University geologists.

Nearly twice as tall as Mount Everest, Arsia Mons is the third tallest volcano on Mars and one of the largest mountains in the solar system. This new analysis of the landforms surrounding Arsia Mons shows that eruptions along the volcano’s northwest flank happened at the same time that a glacier covered the region around 210 million years ago. The heat from those eruptions would have melted massive amounts of ice to form englacial lakes — bodies of water that form within glaciers like liquid bubbles in a half-frozen ice cube.

The ice-covered lakes of Arsia Mons would have held hundreds of cubic kilometers of meltwater, according to calculations by Kat Scanlon, a graduate student at Brown who led the work. And where there’s water, there’s the possibility of a habitable environment.

“This is interesting because it’s a way to get a lot of liquid water very recently on Mars,” Scanlon said.

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Clay-Like Minerals Found On Icy Crust Of Europa

December 11, 2013 Leave a comment

Image credit: NASA/JPL-Caltech/SETI

Image credit: NASA/JPL-Caltech/SETI

A new analysis of data from NASA’s Galileo mission has revealed clay-type minerals at the surface of Jupiter’s icy moon Europa that appear to have been delivered by a spectacular collision with an asteroid or comet. This is the first time such minerals have been detected on Europa’s surface. The types of space rocks that deliver such minerals typically also often carry organic materials.

“Organic materials, which are important building blocks for life, are often found in comets and primitive asteroids,” said Jim Shirley, a research scientist at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. Shirley is giving a talk on this topic at the American Geophysical Union meeting in San Francisco on Friday, Dec. 13. “Finding the rocky residues of this comet crash on Europa’s surface may open up a new chapter in the story of the search for life on Europa,” he said.

Many scientists believe Europa is the best location in our solar system to find existing life. It has a subsurface ocean in contact with rock, an icy surface that mixes with the ocean below, salts on the surface that create an energy gradient, and a source of heat (the flexing that occurs as it gets stretched and squeezed by Jupiter’s gravity). Those conditions were likely in place shortly after Europa first coalesced in our solar system.

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Two Suns Are Probably Better Than One, Or Not?


An International Collaboration of FACom researchers and Astronomers of the University of Texas (El Paso) and New Mexico State University, have discovered a physical mechanism that could make binary stars more hospitable to habitable planets than single stars. The discovery could imply a modification in the estimations of the number of planets potentially harboring life in the Galaxy and in the future selection of targets for the search of life elsewhere.

Habitability is the term astronomers use for referring to the general condition a planet must fulfill in order to be suitable for life. It has been customary to think that habitability is determined mainly by the amount of light a planet receives from its host star. If the planet receives too much light it is too hot and water will be boiling in its atmosphere (if it has one!). On the other hand, if the planet is too far and light from the star shines weakly, the surface is too cold and water becomes frozen. In the middle between these extremes lies the so called “radiative habitable zone” also nicknamed the “Goldilocks Zone”.

But planets in the Goldilocks Zone need to meet other conditions to be considered actually habitable. One of the most important is having a dense and wet atmosphere where heat could be trapped and water could condensate at the surface. But preseving an atmosphere is a real challenge for a young planet.

Full Story: http://urania.udea.edu.co/sitios/facom/press.php?

Cassini Finds Hints Of Activity At Saturn Moon Dione


Image credit: NASA/JPL/Space Science Institute

Image credit: NASA/JPL/Space Science Institute

From a distance, most of the Saturnian moon Dione resembles a bland cueball. Thanks to close-up images of a 500-mile-long (800-kilometer-long) mountain on the moon from NASA’s Cassini spacecraft, scientists have found more evidence for the idea that Dione was likely active in the past. It could still be active now.

“A picture is emerging that suggests Dione could be a fossil of the wondrous activity Cassini discovered spraying from Saturn’s geyser moon Enceladus or perhaps a weaker copycat Enceladus,” said Bonnie Buratti of NASA’s Jet Propulsion Laboratory in Pasadena, Calif., who leads the Cassini science team that studies icy satellites. “There may turn out to be many more active worlds with water out there than we previously thought.”

Other bodies in the solar system thought to have a subsurface ocean – including Saturn’s moons Enceladus and Titan and Jupiter’s moon Europa – are among the most geologically active worlds in our solar system. They have been intriguing targets for geologists and scientists looking for the building blocks of life elsewhere in the solar system. The presence of a subsurface ocean at Dione would boost the astrobiological potential of this once-boring iceball.

Full Story: http://www.jpl.nasa.gov/news/news.php?release=2013-178

New ET Detection Method Leads To Quest For World’s Largest Telescope


Until recently, one of the ultimate mysteries of the universe — how many civilizations may exist on planets orbiting other stars in the Milky Way Galaxy — relied on the possibility of detecting intelligent beings by radio signals. Now a team of astronomers, engineers, and physicists from the University of Hawaii, the University of Freiburg, and elsewhere has proposed a new and powerful technique to search for intelligent life.

The revolutionary method is described by four of the team’s astronomers in the June 2013 issue of Astronomy magazine, the world’s largest magazine on the subject, with a print and web readership of half a million each month. The story, “How to Find ET with Infrared Light,” was written by Jeff R. Kuhn of the University of Hawaii’s Institute for Astronomy, Svetlana V. Berdyugina of the University of Freiburg and the Kiepenheuer Institute for Solar Physics in Germany, David Halliday of Dynamic Structures, Ltd., in British Columbia, and Caisey Harlingten of the Searchlight Observatory Network in The Grange, Norwich, England.

Rather than looking for radio waves, the team suggests searching for the heat signatures of nearby planets, which requires a giant telescope that could detect infrared radiation directly from an exoplanet, thus revealing the presence of a civilization.

“The energy footprint of life and civilization appears as infrared heat radiation,” says Kuhn, the project’s lead scientist. “A convenient way to describe the strength of this signal is in terms of total stellar power that is incident on the host planet.” The technique arises from the fact that a civilization produces power that adds to the heat on a planet, beyond the heat received from its host star. A large enough telescope, idealized for infrared detection, could survey planets orbiting stars within 60 light-years of the Sun to see whether or not they host civilizations.

Astronomy Magazine Article (PDF): http://www.astronomy.com/~/media/Files/PDF/Magazine%20articles/ET-with-infrared-light.pdf

NASA Curiosity Rover Team Selects Second Drilling Target On Mars


The team operating NASA’s Curiosity Mars rover has selected a second target rock for drilling and sampling. The rover will set course to the drilling location in coming days.

This second drilling target, called “Cumberland,” lies about nine feet (2.75 meters) west of the rock where Curiosity’s drill first touched Martian stone in February. Curiosity took the first rock sample ever collected on Mars from that rock, called “John Klein.” The rover found evidence of an ancient environment favorable for microbial life. Both rocks are flat, with pale veins and a bumpy surface. They are embedded in a layer of rock on the floor of a shallow depression called “Yellowknife Bay.”

“We know there is some cross-contamination from the previous sample each time,” said Dawn Sumner, a long-term planner for Curiosity’s science team at the University of California at Davis. “For the Cumberland sample, we expect to have most of that cross-contamination come from a similar rock, rather than from very different soil.”

Full Story: http://www.jpl.nasa.gov/news/news.php?release=2013-159

Looking For Life By The Light Of Dying Stars


Because it has no source of energy, a dead star — known as a white dwarf — will eventually cool down and fade away. But circumstantial evidence suggests that white dwarfs can still support habitable planets, says Prof. Dan Maoz of Tel Aviv University’s School of Physics and Astronomy.

Now Prof. Maoz and Prof. Avi Loeb, Director of Harvard University’s Institute for Theory and Computation and a Sackler Professor by Special Appointment at TAU, have shown that, using advanced technology to become available within the next decade, it should be possible to detect biomarkers surrounding these planets — including oxygen and methane — that indicate the presence of life.

Published in the Monthly Notices of the Royal Astronomical Society, the researchers’ “simulated spectrum” demonstrates that the James Webb Space Telescope (JWST), set to be launched by NASA in 2018, will be capable of detecting oxygen and water in the atmosphere of an Earth-like planet orbiting a white dwarf after only a few hours of observation time — much more easily than for an Earth-like planet orbiting a sun-like star.

Full Story: http://www.aftau.org/site/News2?page=NewsArticle&id=18487

Universality Of Circular Polarization In Star- And Planet-Forming Regions: Implications For The Origin Of Homochirality Of Life


A research team with Jungmi KWON (GUAS/NAOJ) has performed deep imaging linear and circular polarimetry of the ‘Cat’s Paw Nebula’ (NGC 6334) located in the constellation Scorpius, successfully detecting high degrees of circular polarization (CP) of as much as 22% in NGC 6334. The detected CP degree is the highest ever observed.

In addition, the team has presented the first systematic survey of a combination of linear and circular polarimetry in nine star- and planet-forming regions. As the results of statistical analysis of observations of various star-forming regions, CPs were detected in nine star- and planet-forming regions. Putting it differently, it can be said that CP is a universal feature of star- and planet-forming regions. The team’s findings enable us to obtain information about magnetic fields of circumstellar structures around protostars, which is difficult to obtain using existing methods.

There is a hypothesis that large CP causes homochirality of amino acids and that left-handed amino acids come from outer space. The team’s findings imply an extraterrestrial origin of homochirality of life, from the universality of CP detected in star- and planet-forming regions.

This research is part of an ongoing survey project of wide-field near-infrared (JHKs) imaging polarimetry for star-forming regions (PI: Motohide TAMURA, University of Tokyo/NAOJ). Doctoral student Jungmi KWON, who is contributing to the project, led this research with nine international researchers from Japan and the United Kingdom. The team’s findings were published in the Astrophysical Journal Letter on March 1, 2013.

Full Story: http://esppro.mtk.nao.ac.jp/Members_PRESS/201304/index_E.html

Has Kepler Found Ideal SETI-Target Planets?


NASA’s Kepler mission has discovered a new planetary system that is home to five small planets around a slightly smaller star than our Sun. Two of them are super-Earth planets, most likely made of rock or ice mixed with rock, which are located in the habitable zone of their host star. This discovery is providing a target for the SETI search, since if life has thrived on these worlds and reached a point where civilization has developed complex technology, it may be detectable.

When the NASA Kepler mission was launched on March 9, 2007, the Delta II rocket was carrying the hope of a large community of scientists who dedicate their work to studying extra-solar planets, planets in orbit around other stars. The Kepler mission’s main scientific objective is exploration of the structure and diversity of planetary systems. It accomplishes this goal by staring almost constantly at a large field composed of about 150,000 stars to detect small dips in brightness due to the transits of a planet.

Full Story: http://www.seti.org/seti_kepler_62