Grady—a member of the Euro-Cares project designed to curate samples returned from missions to asteroids, Mars, the Moon and comets—reveals: "Space agencies from across the world are working to eventually send humans to Mars.
And so one of the big steps in that process is actually to bring a rock back from Mars. Currently, we boil all the equipment in acid, or we heat it to very high temperatures, before we send it off. Meanwhile Professor Grady says that by looking at the bigger, inter-planetary picture, Earth's own ecological situation is brought into sharp focus. She says: "We could be all there is in the galaxy.
And if there's only us, then we have a duty to protect the planet. Professor Grady has also been looking at the bigger picture by focusing on the minutiae—a single grain of rock, the size of a full stop.
This speck was brought to Earth in by the Japanese "Hayabusa' mission—where a robotic spacecraft was sent to the near-Earth asteroid ' Itokawa' in order to collect a sample.
She adds: "When we look at this grain, we can see that most of it is made up of silicates, but it's also got little patches of carbon in it—and that carbon is extra-terrestrial, because it also contains nitrogen and hydrogen, which is not a terrestrial signature. More from Astronomy and Astrophysics.
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You can unsubscribe at any time and we'll never share your details to third parties. Of course, seeing how Earth-like life would evolve over billions of years in a frigid, buried ocean would be pretty exciting, too. And if we discover just one such "second genesis" in our solar system, we would know that life is no miracle and must be common throughout the cosmos. We may be on the verge of answering some of these profound questions. For example, NASA is developing a mission called Europa Clipper , which will characterize the satellite's ocean and scout out potential touchdown sites for a future life-hunting lander mission, among other tasks.
Clipper is scheduled to launch in the early to mids, but the lander's future is murky; though Congress has ordered NASA to develop the surface mission, it's unclear if the funding will come through to make that happen. This robotic rotorcraft could potentially spot signs of life in the big moon's air, if any are there to be found. And over the longer haul, researchers are looking into ways to get a robot through the ice shells of Europa and Enceladus and into their possibly life-supporting oceans.
No such mission is on the books, but one could get off the ground in the s if we're lucky. There will be serious astrobiological action closer to home soon, too. Both of these wheeled robots will focus on finding signs of ancient, not currently existing, Red Planet organisms. Of course, chances are decent that Martians, if they exist, are related to us. The radiation splits apart water molecules H2O, made of oxygen and hydrogen in Europa's extremely tenuous atmosphere.
The hydrogen floats away and the oxygen stays behind. Oxygen is a very reactive element, and potentially could be used in chemical reactions that release energy, which lifeforms could exploit. If the oxygen somehow make its way to the ocean, it could possibly provide chemical energy for microbial life. If Europa does have a salty ocean, chemical reactions between the water and the rocks on the ocean floor could create hydrogen-rich materials.
And if there are areas where the ocean interacts with hot rock, then, like hydrothermal vents in Earth's oceans, that water could be pouring out chemical nutrients to power life. In short, Europa may have a variety of processes that work together to make the chemical energy available for powering life processes of simple organisms like bacteria. Why Europa? Europa could have the essential ingredients needed for life: Water Chemistry Energy. Read More.
Europa's Ocean Ascending. The image on the left shows a region of Europa's crust made up of blocks which are thought to have broken apart and "rafted" into new positions. Scientists are studying processes on the icy surface as they prepare to explore. The rocky layer underneath may be hot enough to melt, leading to undersea volcanoes. Scientists have theorized on the origin of the water plumes possibly erupting from Jupiter's moon Europa.
A likelier source of energy, he concludes, may come from fast-moving, charged particles that pound Europa from the atmosphere of Jupiter. Jupiter has the strongest magnetic field of any planet," Chyba says, more than 10 times stronger than Earth's. When protons, electrons and other particles from space get trapped in Jupiter's magnetosphere, they are accelerated to extremely high velocities.
Europa's orbital path around Jupiter lies deep within this powerful magnetic field, so it receives a continuous barrage of electrified particles or ions. According to Chyba, when these ions slam into the icy surface of the moon, chemical reactions are likely to occur, transforming frozen molecules of water and carbon dioxide into new organic compounds such as formaldehyde.
It turns out that one of the most common bacteria on Earth, Hyphomicrobium , survives on formaldehyde as its sole source of carbon, and Chyba believes that similar formaldehyde-feeding microbes could be alive and swimming in Europa's subsurface ocean. In addition to creating organic fuels, radiation from Jupiter also may drive chemical reactions that produce oxidants -- molecules such as oxygen and hydrogen peroxide that can be used to burn formaldehyde and other carbon-based fuels.
But Chyba notes that the oxidant and organic molecules formed on Europa's frigid surface "are biologically relevant only if they reach the ocean. The problem is that, if there is a liquid ocean on Europa, it's hidden beneath an ice sheet about 50 to miles 80 to km thick.
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