How Jupiter Moon Europa's Underground Ocean Was Discovered
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
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 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.
Sunday, May 19 2013 7:54 PM EDT2013-05-19 23:54:08 GMT
KHQ.COM - The 2013 Spokane Lilac Festival Armed Forces Torchlight Parade is in the books. >>
KHQ.COM - The 2013 Spokane Lilac Festival Armed Forces Torchlight Parade is in the books. With tens of thousands of people in downtown Spokane watching the parade, the floats, the marching bands, we know you took plenty of pictures! Well, we want to see them!>>
Sunday, May 19 2013 10:30 AM EDT2013-05-19 14:30:26 GMT
KHQ.COM - The results of the 2013 Spokane Lilac Festival Armed Forces Torchlight Parade are coming in. We'll post them as we get them.>>
KHQ.COM - The results of the 2013 Spokane Lilac Festival Armed Forces Torchlight Parade are coming in. We'll post them as we get them. In the meantime, if you have any photos from Saturday night's parade and want to submit them for a slideshow, please send them to firstname.lastname@example.org>>
Monday, May 20 2013 4:10 PM EDT2013-05-20 20:10:47 GMT
BOZEMAN, Mont. (AP) - The "Today" show will be broadcasting live from Yellowstone National Park as part of a weeklong travel series.>>
BOZEMAN, Mont. (AP) - The "Today" show will be broadcasting live from Yellowstone National Park as part of a weeklong travel series. All five of the NBC show's anchors will be on the air at Old Faithful starting at 5 a.m. Tuesday.
Monday, May 20 2013 2:21 PM EDT2013-05-20 18:21:01 GMT
COLORADO SPRINGS, Colo. (AP) - It was a bigger-than-average tree rescue for firefighters in Colorado Springs.>>
COLORADO SPRINGS, Colo. (AP) - It was a bigger-than-average tree rescue for firefighters in Colorado Springs. They had to use a ladder truck to reach a black bear after it fell asleep in a tall pine tree after being tranquilized Sunday.>>
Monday, May 20 2013 2:07 PM EDT2013-05-20 18:07:32 GMT
PHOENIX (AP) - Jodi Arias' lawyers have asked to withdraw from the case and say they won't call any witnesses in the penalty phase of her trial.>>
PHOENIX (AP) - Jodi Arias' lawyers have asked to withdraw from the case and say they won't call any witnesses in the penalty phase of her trial. The stunning declaration came Monday after the judge denied their request for a mistrial based on a key witness receiving death threats.
Monday, May 20 2013 11:19 AM EDT2013-05-20 15:19:00 GMT
KHQ.COM - United Airlines is getting its 787s back in the air today. United's first 787 flight on Monday is scheduled for 11 a.m. from Houston to Chicago.>>
KHQ.COM - United Airlines is getting its 787s back in the air. The planes are returning after a four-month grounding because of smoldering batteries on 787s owned by two other airlines. The incidents included an emergency landing of one plane, and a fire on another.>>
Sunday, May 19 2013 1:15 PM EDT2013-05-19 17:15:48 GMT
ZEPHYRHILLS, Fla. (AP) - Some lucky person walked into a Publix supermarket in suburban Florida.>>
ZEPHYRHILLS, Fla. (AP) - Some lucky person walked into a Publix supermarket in suburban Florida over the past few days and bought a winning Powerball ticket now worth an estimated $590.5 million. The jackpot is the highest in Powerball history.>>