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.”
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.
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.
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?
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.
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
Gone are the days of being able to count the number of known planets on your fingers. Today, there are more than 800 confirmed exoplanets — planets that orbit stars beyond our sun — and more than 2,700 other candidates. What are these exotic planets made of? Unfortunately, you cannot stack them in a jar like marbles and take a closer look. Instead, researchers are coming up with advanced techniques for probing the planets’ makeup.
One breakthrough to come in recent years is direct imaging of exoplanets. Ground-based telescopes have begun taking infrared pictures of the planets posing near their stars in family portraits. But to astronomers, a picture is worth even more than a thousand words if its light can be broken apart into a rainbow of different wavelengths.
Those wishes are coming true as researchers are beginning to install infrared cameras on ground-based telescopes equipped with spectrographs. Spectrographs are instruments that spread an object’s light apart, revealing signatures of molecules. Project 1640, partly funded by NASA’s Jet Propulsion Laboratory, Pasadena, Calif., recently accomplished this goal using the Palomar Observatory near San Diego.