Science

Europa water plume: Another step toward living on a moon

Europa water plume: Another step toward living on a moon

Nasa's Galileo spacecraft spent eight years in orbit around Jupiter and made its closest pass over Europa, a moon about the size of our own, on 16 December 1997.

But the sensitivity of telescopic data is limited, and more was needed to be sure that these were really plumes, the researchers said.

The research team behind the study notes that this new finding makes Europa one of the most promising places in the solar system to search for life.

"These results provide strong independent evidence of the presence of plumes at Europa", he concluded in a paper published Monday in the journal Nature Astronomy.

Kivelson was the principal investigator for Galileo's magnetometer and helped make the discovery of the subsurface ocean on Europa.

The 20-year-old data was captured on Galileo's closest encounter with the moon but scientists were unable to explain the unexpected signals at the time.

"The idea that Europa might possess plumes seems to be becoming more and more real, and that's very good news for future exploration", said Xianzhe Jia, a space physicist at the University of MI and the lead author of the new paper on the phenomenon.

So why did the Galileo team miss the data during the initial flyby in 1997? By and large, those model predictions matched their observations, ruling out Jupiter as the source and strengthening the case for watery plumes erupting from Europa's depths.

More news: Mike Pompeo points to potential security assurances for Kim Jong Un
More news: 'Killer' US diplomat Col Joseph flees home
More news: Rivals of Iraqi PM 'make gains' in vote count

"When we first saw those images, I think a lot of us in the community were very excited", says planetary scientists Xianzhe Jia from the University of MI.

Jia's team was inspired to dive back into the Galileo data by Melissa McGrath of the SETI Institute in Mountain View, California. "It's incredible how hard it is to anticipate something that just hasn't happened before", she said. Data from NASA's Galileo orbiter launched a generation ago yields new evidence of plumes, eruptions of water vapor, from Jupiter's moon Europa. This new analysis adds backing to theories that an ocean of liquid salt water exists below the ice. There, microbes don't receive energy from sunlight but use methanogenesis, a process that reduces carbon dioxide with hydrogen, to form methane. Then the Galileo mission reached Europa in 1996, and Kivelson's detections revealed that there was an ocean on another planet.

A bit smaller that Earth's moon, Europa's ocean resides under an ice layer 10 to 15 miles (15 to 25 km) thick, with an estimated depth of 40 to 100 miles (60 to 150 km). "I made certain that the Europa orbiter and lander are the only missions it's illegal for NASA not to fly", says Rep. John Culberson (R-Texas), member of the House Appropriations Committee and former chair of the subcommittee with jurisdiction over NASA. The Europa Clipper, named for the innovative, streamlined ships of the 1800s, will launch in the 2020s and arrive at Europa after a few years.

Whereas Galileo didn't know that it was flying through a plume and was incapable of collecting material from the plume, Europa Clipper will be able to gather material from plumes if it can fly through them.

NASA originally wanted to use the Clipper mission to land a probe on Europa for direct sampling, and one idea was for a robot melt its way down through the ice and into the waters below, but budget cuts put paid to that.

Do you believe that Jupiter's icy moon Europa could potentially support alien life? Not only do the plumes suggest that subsurface ocean likely exists, but it also means the Clipper, and any future mission, can just fly through the spewing mist for a sample, instead of hacking through the icy crust.

"And it's those electrically charged parts of the plume that cause the changes in the magnetic field and change the density of the electrons in the environment that were measured by the plasma wave instrument". That's the big picture.


  • Overwatch will be free to play this month on Xbox One

    Overwatch will be free to play this month on Xbox One

    In addition, deathmatch will include a new competitive mode that has placement matches, skill rating tiers, and leaderboards. Blizzard said it's also adding more than 50 new items to the game, including eight new legendary skins and three epic skins.
    Dozens killed in Gaza as USA  opens Jerusalem embassy

    Dozens killed in Gaza as USA opens Jerusalem embassy

    Even as Palestinians' anger erupted, American and Israeli officials celebrated President Trump's move of the embassy to Jerusalem. She said Jerusalem was an internationally recognised disputed territory and a "fair division" was the only hope of peace.
    Weinstein trying to discredit women of colour: Hayek

    Weinstein trying to discredit women of colour: Hayek

    Hayek also remarked on her allegation of sexual harassment made against Harvey Weinstein in an op-ed in December. Hayek said men should not be afraid of change in the gender balance. "The actors have to say: 'OK, time's up .
  • Sichuan Airlines co-pilot was sucked halfway out of window, captain says

    Sichuan Airlines co-pilot was sucked halfway out of window, captain says

    On May 3, another Southwest Airlines flight made an emergency landing after a cabin window pane cracked in flight. Images posted on the official People's Daily newspaper online appear to show a cockpit window completely missing.
    Parents charged after 10 kids found living in terrible  conditions, police say

    Parents charged after 10 kids found living in terrible conditions, police say

    Fairfield police arrested Rogers' 29-year-old husband Jonathan Michael Allen on Friday after a six-week investigation. Rogers, who was arrested March 31 and released after posting $10,000 bail, was booked for child neglect.
    Arizona softball to host regional

    Arizona softball to host regional

    The Bison have a 9-16 record in the NCAA Tournament, including winning the Oklahoma Regional in 2009. On March 5, 2016, Arizona defeated SFU by a 6-4 score in the last meeting.
  • Andrew McCutchen's return to Pittsburgh was awesome

    Andrew McCutchen's return to Pittsburgh was awesome

    Polanco's was his second over his past three games and his eighth of the season. Hernandez led off with his second homer , to left, for a 1-0 Giants lead.
    UEFA Champions League Winners Odds - Real Madrid vs. Liverpool

    UEFA Champions League Winners Odds - Real Madrid vs. Liverpool

    Gareth Bale impressed his manager with two goals. "We will face a team who are very enthusiastic, with very good attacking players".
    'Gotham' Is Renewed for Fifth and Final Season by FOX

    'Gotham' Is Renewed for Fifth and Final Season by FOX

    Do you want to see more Gotham? Well, fortunately, the series has managed to secure a fifth season pick-up. After a disjointed and overly busy first season, Gotham found its feet during season two.
  • Pompeo: US to help North Korea economy if it gives up nuke

    Pompeo: US to help North Korea economy if it gives up nuke

    North Korea has gone back on peace overtures before, but an IN congressman says there are signs the country is serious this time. The North Korean government sees the outside world with distrust and restricts its own people from contacting that world.
    How to watch a lost Pyramid-size asteroid buzz by Earth

    How to watch a lost Pyramid-size asteroid buzz by Earth

    It can be inferred from this that the asteroid would pass somewhere midway in between the moon and the Earth . Astronomers hope to further observe asteroid 2010 WC9 in order to better refine its orbit .
    Malaysia's ex-PM Najib barred from leaving

    Malaysia's ex-PM Najib barred from leaving

    Najib has said the deposit was a donation by an unnamed member of the Saudi royal family which had been largely returned. Dr Mahathir and Deputy Prime Minister Wan Azizah Wan Ismail, the wife of his jailed ally Anwar Ibrahim, make up the rest.