How Jupiter Moon Europa's Underground Ocean Was Discovered - Spokane, North Idaho News & Weather KHQ.com

How Jupiter Moon Europa's Underground Ocean Was Discovered

Posted: Updated:

YAHOO.COM - This is Part 4 of a six-part series telling the story of humankind's efforts to understand the origins of life, by looking for it in extreme environments where life thrives without relying on the sun as an energy source.

It follows an oceanographic expedition to the Mid-Cayman Rise led by Chris German of the Woods Hole Oceanographic Institution, and NASA's efforts to plan a future mission to Jupiter's moon Europa. By understanding how life can live without the sun, we may discover how life began on our planet, and whether or not Earth is the only place in the universe capable of supporting a biosphere.

Nineteen seventy-seven was the kind of year that only comes around once every 176 years. That's how often the outer planets of our solar system (Jupiter, Saturn, Uranus and Neptune — sorry, Pluto) line up just right in their orbits around the sun to allow for a spacecraft to slingshot past all four of them.

Rather than wait until 2153, NASA decided to take advantage of the opportunity of ‘77. The space agency launched the twin 1-ton space probe emissaries, Voyager 1 and Voyager 2, from Florida's Cape Canaveral in September and August of that year, respectively. [Voyager: Humanity's Farthest Journey (Video)]

The Voyager mission was only supposed to last for four years, and technically, both spacecraft were only heading to Jupiter and Saturn. Mission designers had planned Voyager 2's trajectory so it could continue on toward Uranus and Neptune if Voyager 1 (which launched second but took a faster route) succeeded at Jupiter and Saturn. Fifty-two worlds and 12 years later, the Volkswagen Beetle-size probes brought new meaning to success in planetary science.

Their journeys to the outer planets gave humanity a front-row seat to see half the solar system up close in great detail for the first time (NASA's Pioneer 10 and 11 spacecraft had zipped past Jupiter in 1973 and 1974, but they were far less capable and yielded significantly less data).

The Voyager probes sent back stunning images of the Great Red Spot on Jupiter that revealed it to be a raging storm the size of two Earths. Saturn's rings —thought to be smooth and ordered — were revealed to be oddly intertwining and kinked. The mission further discovered that Uranus orbits on its side and Neptune sports the fastest winds in the solar system.

And that was just the planets. The 48 moons captured by the Voyager craft were arguably even more striking than their parent planets.

Jupiter's Galilean moons

The largest of Jupiter's satellites are the four Galilean moons — Io, Ganymede, Callisto, and Europa — which are named for their discoverer, Italian astronomer Galileo Galilee.

Galileo spotted them in 1610 after tweaking his telescope to reach a magnifying capability of 20x (20 times better than the naked eye). These four worlds were the first moons discovered orbiting a planet other than Earth. (Since our own moon is awfully hard to miss, we'll never know who was the first person to look up and say, "What's that?" Thus, it's probably safe to credit Galileo with discovering moons.)

The Galilean moons proved to be full of surprises at close range. An active volcano was spotted on the innermost of the Galilean moons, Io, spouting ash and gases a whopping 174 miles (280 kilometers) in height — the first evidence of active volcanism beyond Earth.

The mission team would find half a dozen more erupting volcanoes on Io over the course of the mission. Team leader Brad Smith said this made Io look like a pizza. Later, astronomers would identify more than 400 active volcanoes there, making Io the most geologically active world in our solar system.

You'd think such a world might be a hot one, but you'd be wrong. Most of Io's surface is minus 238 degrees Fahrenheit (minus 150 degrees Celsius). Colossal eruptions of gases condense and fall back to the surface as pastel yellow, orange and bluish-white sulfur dioxide snow.

This makes Io a surrealist's dream: fiery hell plus winter wonderland with an everything-on-it sulfuric pizza surface and the churning clouds of Jupiter looming above hazy skies.

  • Most Popular StoriesMost Popular StoriesMore>>

  • PHOTOS: Hobo Spider season has arrived

    PHOTOS: Hobo Spider season has arrived

    Friday, August 29 2014 5:37 PM EDT2014-08-29 21:37:17 GMT
    KHQ.COM - Mid August is about the time that we start to see spiders come into our homes, particularly the hobo spider. August and September is mating season for the hobo and that means you may be seeing more funnel-like webs in and around your home. Males are on a mission to find a female which is why they are a lot more active at this time.>>
    KHQ.COM - Mid August is about the time that we start to see spiders come into our homes, particularly the hobo spider. August and September is mating season for the hobo and that means you may be seeing more funnel-like webs in and around your home. Males are on a mission to find a female which is why they are a lot more active at this time.
    >>
  • Priest Lake Auction: Saying goodbye to home

    Priest Lake Auction: Saying goodbye to home

    Wednesday, August 27 2014 10:50 PM EDT2014-08-28 02:50:23 GMT
    PRIEST LAKE, Idaho - After years of obstacles for 61 Priest Lake lot lessees, the end comes on Thursday, August 28th. >>
    PRIEST LAKE, Idaho - After years of obstacles for 61 Priest Lake lot lessees, the end comes on Thursday, August 28th. People who have been leasing land from the state, some more than 40 years, will find out if they get to keep their property in an auction.Back in 2010, the State of Idaho decided to divest more than 300 lake lots on Priest Lake.
    >>
  • PHOTOS: Priest Lake lots auctioned off

    PHOTOS: Priest Lake lots auctioned off

    Thursday, August 28 2014 8:46 PM EDT2014-08-29 00:46:58 GMT
    PRIEST LAKE, Idaho - 61 cottages sites on Priest Lake were auctioned off in Coeur d'Alene on Thursday. >>
    PRIEST LAKE, Idaho - 61 cottages sites on Priest Lake were auctioned off in Coeur d'Alene on Thursday. For years, those already living on the sites leased the land from the State of Idaho, but the State was looking to sell. Residents already living on the sites showed up on Thursday to buy them back, and many were successful. 


    >>
  • National NewsMore>>

  • UPDATE: Joan Rivers 'Resting Comfortably' at Mount Sinai in New York

    UPDATE: Joan Rivers 'Resting Comfortably' at Mount Sinai in New York

    Friday, August 29 2014 12:45 AM EDT2014-08-29 04:45:02 GMT
    NEW YORK (AP) - Comedian Joan Rivers is in a New York City hospital, according to police and hospital officials who say she was rushed there from a doctor's office after going into cardiac arrest.Rivers' daughter later issued a statement about her mother's condition.>>
    NEW YORK (AP) - Comedian Joan Rivers is in a New York City hospital, according to police and hospital officials who say she was rushed there from a doctor's office after going into cardiac arrest.Rivers' daughter later issued a statement about her mother's condition.
    >>
  • VA: No proof delays in veteran care caused hospital deaths

    VA: No proof delays in veteran care caused hospital deaths

    Tuesday, August 26 2014 9:11 PM EDT2014-08-27 01:11:37 GMT
    KHQ.COM- The Department of Veterans Affairs says there's no proof that delays in care caused any deaths at the VA hospital in Phoenix, Ariz.Revelations that as many as 40 veterans died while awaiting care rocked the agency this past spring, bringing to light scheduling problems and allegations of misconduct at other hospitals as well.NBC News obtained a draft report from the VA's Office of Inspector General Tuesday. The draft report says while investigators found substantial delays in care an...>>
    KHQ.COM- The Department of Veterans Affairs says there's no proof that delays in care caused any deaths at the VA hospital in Phoenix, Ariz.Revelations that as many as 40 veterans died while awaiting care rocked the agency this past spring, bringing to light scheduling problems and allegations of misconduct at other hospitals as well.NBC News obtained a draft report from the VA's Office of Inspector General Tuesday. The draft report says while investigators found substantial delays in care an...>>
  • UPDATE: Sergeant who shot herself at Fort Lee dies

    UPDATE: Sergeant who shot herself at Fort Lee dies

    Monday, August 25 2014 6:58 PM EDT2014-08-25 22:58:27 GMT
    Police officer patrols the entrance of Fort Lee in VirginiaPolice officer patrols the entrance of Fort Lee in Virginia
    FORT LEE, Va. (AP) - A commanding general at a Virginia Army base says an enraged soldier with a gun barricaded herself in an office, then shot herself in the head as officials tried to negotiate with her.>>
    FORT LEE, Va. (AP) - A commanding general at a Virginia Army base says an enraged soldier with a gun barricaded herself in an office, then shot herself in the head as officials tried to negotiate with her. Maj. Gen. Stephen R. Lyons says the soldier went on a rampage, throwing objects. >>