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Tagged with “saturn” (5)

  1. The Life Scientific: Michele Dougherty on Saturn

    Michele Dougherty tells Jim Al-Khalili why she diverted the Cassini mission to Saturn.

    The Cassini mission into deep space has witnessed raging storms, flown between Saturn’s enigmatic rings and revealed seven new moons. And, thanks in no small part to Professor Michele Dougherty, it’s made some astonishing discoveries. For the last twenty years, Michele been responsible for one of the key instruments on board Cassini - the magnetometer. In 2005, she spotted a strange signature in the data during a distant fly by of Saturn’s smaller moons, Enceladus and became curious. Now,space missions are planned years ahead of time. Every detail is nailed down. But Michele convinced mission control to divert Cassini from its carefully planned route to take a closer look at Enceladus. And her gamble paid off. Cassini scientists soon discovered jets of water vapour and organic material shooting out of the south pole of Enceladus, not bad for a small moon that could so easily have been ignored. It’s now thought that this tiny moon might be able to support microbial life underneath its icy surface.

    In 2008, Michele was awarded the hugely prestigious Hughes medal for her work - an honour last given to a woman in 1906! She’s also been voted by the UK Science Council as one of the country’s top 100 living scientists. She talks to Jim al-Khalili about growing up in South Africa, moving from mathematics to managing space missions and what they hope will happen when Cassini crashes into Saturn later this year.

    https://www.bbc.co.uk/programmes/b087qjcw

    —Huffduffed by adactio

  2. Carolyn Porco: Searching for Life in the Solar System - The Long Now

    Life nearby

    If we find, anywhere in the universe, one more instance of life besides what evolved on Earth, then we are bound to conclude that life is common throughout the vastness of this galaxy and the 200 billion other galaxies.

    The discovery would change how we think about everything.

    Most of the search for life beyond Earth, Porco explained, is the search for habitats.

    They don’t have to look comfy, since we know that our own extremophile organisms can survive temperatures up to 250°F, total desiccation, and fiercely high radiation, high pressure, high acidity, high alkalinity, and high salinity.

    In our own Solar System there are four promising candidate habitats—Mars, Europa (a moon of Jupiter), Titan (a moon of Saturn), and Enceladus (“en-SELL-ah-duss,” another moon of Saturn).

    They are the best nearby candidates because they have or have had liquids, they have bio-usable energy (solar or chemical), they have existed long enough to sustain evolution, and they are accessible for gathering samples.

    On Mars water once flowed copiously.

    It still makes frost and ice, but present conditions on Mars are so hostile to life that most of the search there now is focussed on finding signs of life far in the past.

    Europa, about the size of Earth’s Moon, has a salty ocean below an icy surface, but it is subject to intense radiation.

    Photos from the Hubble Space Telescope revealed that occasional plumes of material are ejected through Europa’s ice, so future missions to Jupiter will attempt to fly by and analyze them for possible chemical signatures of life.

    The two interesting moons of Saturn are Titan, somewhat larger and much denser than our Moon, and tiny Enceladus, one-seventh the diameter of our Moon.

    Both have been closely studied by the Cassini Mission since

    2004.

    Titan’s hazy atmosphere is full of organic methane, and its surface has features like dunes and liquid-methane lakes “that look like the coast of Maine.”

    But it is so cold, at 300°F below zero, that the chemical reactions needed for life may be too difficult.

    Enceladus looks the most promising.

    Cassini has sampled the plumes of material that keep geysering out of the south pole.

    The material apparently comes from an interior water ocean about as salty as our ocean, and silica particles may indicate hydrothermal vents like ours.

    “I hope you’re gettin excited now,” Porco told the audience, “because we were.”

    The hydrothermal vents in Earth’s oceans are rich with life.

    Enceladus has all the ingredients of a habitat for life—liquid water, organics, chemical energy, salts, and nitrogen-bearing compounds.

    We need to look closer.

    A future mission (arriving perhaps by the 2030’s) could orbit Enceladus and continually sample the plumes with instruments designed to detect signs of life such as complexity in the molecules and abundance patterns of carbon in amino acids that could indicate no biology, or Earth-like biology, or quite different biology.

    You could even look for intact organisms.

    Nearly all of the material in the plumes falls back to the surface.

    Suppose you had a lander there.

    “It’s always snowing at the south pole of Enceladus,” Porco said.

    “Could it be snowing microbes?”

    (A by-the-way from the Q&A:

    Voyager, which was launched 40 years ago in 1977, led the way to the outer planets and moons of our Solar System, and five years ago, Porco pointed out, “It went beyond the magnetic bubble of the Sun and redefined us as an interstellar species.”)

    —Stewart Brand

    http://longnow.org/seminars/02017/jul/24/searching-life-solar-system/

    —Huffduffed by adactio

  3. Magnetic fields of Mars and Saturn

    It is thought planets have dynamos in their centre. This explains the intensity and geometry of the magnetic fields found on the surface. The dynamo is in the form of a fluid sphere of molten iron which is churning around producing electric currents and magnetic fields. But Mars has a strange field. Only the southern hemisphere has a strong magnetic field, emanating from the crust. Secondly, this crustal field is very strong, about ten times what’s found on Earth or other rocky planets. This is one of a range of amazing anomalies with Mars. Saturn has other problems. Its fields are too perfect. Sabine Stanley explains.

    From: http://www.abc.net.au/rn/scienceshow/stories/2010/2881442.htm

    —Huffduffed by adactio

  4. Cassini/Huygens: Rewriting the Textbook on Saturn

    Cassini has given us a whole new view of Saturn, Titan, and other moons of this amazing and beautiful ringed world. Kevin Grazier from Cassini provides an overview of what has been learned so far from the mission and talks with Bob Mitchell, the Cassini Program Manager, and John Smith, the Cassini tour designer.

    http://365daysofastronomy.org/2009/11/12/november-12th-cassinihuygens-rewriting-the-textbook-on-saturn/

    —Huffduffed by adactio

  5. Cover to Cover #322A: Charles Stross

    Hugo Award nominee and winner Charles Stross is in studio to chat about his latest book, Saturn’s Children. Charles explains how the story is really a Heinlein styled period piece, an homage to Heinlein’s late period, and tells the story of an android designed to be a sex robot for humans, only humans have gone extinct before she rolls off the assembly line.

    Why else would a robot have been built with nipples?

    The talk ranges from the appeal of Heinlein, the book sales percentages in the UK, and about the next few books he is working on, a sequl to Halting State, and more in the Merchant Princes series.

    From http://www.dragonpage.com/2008/08/12/cover-to-cover-322a/

    —Huffduffed by adactio