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Last fall, as NASA's celebrated Cassini spacecraft spiraled towards its final, fatal descent into Saturn's clouds, astrochemist Morgan Cable could not help but shed a tear for the school-bus-size orbiter, which became a victim of its own success
Early in its mission, while flying past Saturn's ice-covered moon Enceladus, Cassini discovered in the south pole – a sign that the body contained a subsurface ocean that could harbor life. When the orbiter began to run low on fuel, it smashed itself into a wayward world that would contaminate the potentially habitable world.
Now, from beyond the grave, the spacecraft has yet another prize for scientists. New analysis of cassini data suggests that these feathers capture the environment in the form of complex compounds.
are one of the largest and most complex organics in the solar system – makes the icy moon an even more tantalizing target in the search for extraterrestrial life, said Cable, a research scientist at the Jet Propulsion Laboratory who was not involved in the new research
"This is a powerful study with a powerful result," she said.
The findings published Wednesday in the journal Cassini Instruments – The Cosmic Dust Analyzer and the Ion and Neutral Mass Spectrometer – as the spacecraft flew through Saturn's outermost ring and the plumes of Enceladus (pronounced "en-SELL-a-dus").
Such molecules, such as methane, which consists of four hydrogen atoms attached to a single carbon. The INMS has also detected molecular hydrogen – a chemical characteristic of hydrothermal activity that provides important fuel for microbes living around seafloor winds on Earth.
The molecules reported in the new Nature paper are "orders of magnitude" larger than anything that has been Frank Postberg, a planetary scientist at the University of Heidelberg in Germany. There were some carbon ring structures known to the world of oxygen atoms, oxygen, maybe even nitrogen.
Some of the molecules sensed by the CDA were so large that the instrument could not analyze them. This suggests that the Cassini organics are only fragments of even larger compounds, Postberg said. There are many polymers – many-segmented molecules such as those that make up DNA and proteins – still waiting to be discovered.
"We astrobiologists get excited about larger molecules "said Kate Craft," a planetary scientist at Johns Hopkins University Applied Physics Laboratory who was not involved in the research.
The molecules Cassini has been detected may be produced abiotically – without the involvement of life. But they are also the kinds of compounds that microbes have on microbial metabolisms.
"Put it this way, if they did not have these tests and did not see these larger molecules, [Enceladus] Would not seem to be habitable, "Craft said. "But these findings … are reason to say, 'Hey, we need to go back and take a lot more data.' "
Scientists believe that the gravitational influence of Saturn squeezes and flexes the porous, rocky material at Enceladus's core, generating heat. This heat allows for chemical interactions between the salty ocean and the seafloor. On Earth, such water-rock interactions provide fuel for chemotrophs – bodies that obtain energy by breaking down chemicals in their environments – and support vast ecosystems in the ocean's deepest, darkest depths.
Postberg and his colleagues proposes that the organic Ingeniously, the film is taken from the ocean in the form of a thin film.
Earth's oceans are capped by a similar film, they note – a millimeter-thick blanket of tiny microbes and organic matter that serves as an important interface between sea and sky. Research shows that this layer helps drive weather; Incentives for the formation of clouds in the air, where they provide a nucleus around which water can condense to form clouds and fog
A similar process on the surface of Enceladus' s ocean may form ice crystals with organics at their core, Postberg said. These grains are then sucked upward by cracks in the moon's crust called "tiger stripes" and then flung into the vacuum of space.
Enceladus's feathers are extremely tenuous – and more The results of this study by Postberg said, "Enceladus" shows that it is a spacecraft that is flying through the air.
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Cable is deputy project scientist for a concept called Enceladus Life Finder, which would be more advanced than the ones on Cassini to sample the feat during a series of flybys. The role of NASA and the role of the United States in the development of the United States of America.
She, Postberg and Craft. 19659002] "Enceladus is screaming at us that it has all the ingredients for life, we know it: water, chemistry, organics," Cable said. "We have to go back."
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