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Is There Life on Enceladus?

  • Posted 08.28.14
  • NOVA

NASA's Cassini mission to Saturn made surprising discoveries about Enceladus, one of Saturn’s 62 moons. Carolyn Porco, leader of the Cassini mission's science imaging team, describes some of the features Cassini observed on this icy moon, including a series of large cracks named "tiger stripes," through which jets of frozen vapor shoot upward into space. She believes this frozen moon may be the best candidate to harbor life beyond Earth.

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Transcript

CAROLYN PORCO: Cassini's mission, from the outset, was to investigate everything we could about the Saturn system. It is a major exploratory expedition.

NARRATOR: Cassini gives scientists their best view yet of this mysterious planetary system.

CAROLYN PORCO: Cassini was outfitted with the most sophisticated suite of scientific instruments ever carried into the outer solar system. It has cameras, spectrometers. It is really the farthest robotic outpost that humanity has ever established, around the sun.

NARRATOR: Seven years after launch, Cassini finally enters orbit around Saturn.

These images reveal the rings in unprecedented detail. They stretch out across hundreds of thousands of miles, yet in places, they are just tens of feet thick.

Using its instruments to analyze wavelengths of reflected light, Cassini confirms these majestic rings are made of billions of shining particles of almost pure water ice. They range in size from a grain of dust to the size of a mountain.

After nearly eight months collecting data of Saturn and its rings, Cassini makes its way to one of the closer moons.

This tiny ball of ice, only 300 miles across, is Enceladus.

These Cassini images reveal a glistening white surface, unlike any other of Saturn's moons. It is carved with crevasses, ridges and cracks.

And stretching out across the south pole, Cassini photographs these strange large cracks, seen here in blue; four parallel fissures, scientists named the "tiger stripes." They are 75 miles long and hundreds of feet deep. They look a lot like fault lines on Earth.

CAROLYN PORCO: Enceladus was a major focus for the Cassini mission. It was clear that there had been something going on on Enceladus, in the past. The question was, was there anything going on on Enceladus at present.

NARRATOR: On another fly-by, Cassini's thermal imaging sensors reveal something unexpected. At the south pole, the tiger stripes should be colder than the rest of the moon, but they are radiating heat. Though still a frigid minus-120 degrees, the cracks are more than 200 degrees warmer than most of the moon.

Then, as Cassini changes its orientation, it sees Enceladus silhouetted by the sun and vast jets of ice erupting into space.

These actual images reveal the jets are blasting hundreds of miles out from the tiger stripes.

Carolyn and her team are stunned.

CAROLYN PORCO: Never did we expect that were going to see something like a whole forest of jets shooting hundreds of kilometers into the sky above Enceladus. It was like nothing we'd ever seen before.

NARRATOR: Could Enceladus also have an internal energy source like Io and Europa? Scientists believe that when Enceladus orbits the massive Saturn, friction from gravitational forces causes it to heat up, melting ice in the moon's interior in the same way as on Europa.

They believe the jets consist of liquid water, vaporizing and freezing, as it meets the cold vacuum of space. They shoot upwards at 1,200 miles per hour.

CAROLYN PORCO: Enceladus is being flexed as it's orbiting Saturn. That's like flexing a paperclip. It creates heat inside, and we think the heat maintains liquid under the surface.

NARRATOR: Excited by this discovery, the team programs Cassini to fly through the jets and collect particles. After several fly-throughs, Cassini's spectrometers detect, in the jets, some of the basic chemical building blocks of life.

CAROLYN PORCO: That was tremendously exciting to find, because not only do we think there's liquid water there, not only is there an enormous amount of excess heat, but we also have organic materials. That, I mean, that is the trifecta that we're looking for, the three main ingredients for a habitable zone.

Credits

FINDING LIFE BEYOND EARTH: ARE WE ALONE?

Written, Produced and Directed by
Oliver Twinch

Produced in cooperation with NASA and the National Institute of Aerospace

ASSISTANT PRODUCER
Alexis Burke
EDITED BY
Mairin O’Faolain
Dudley Sargeant
Nigel Barker
CAMERA
Jonathan Dacey
NARRATED BY
Jay O. Sanders
SOUND RECORDISTS
Percy Urgena
Gregg Hinnen
Haven McKinney
MUSIC
Universal Audio Network
VISUAL EFFECTS
Prime Focus
VISUAL EFFECTS SUPERVISOR FOR PRIME FOCUS
Simon Clarke
VISUAL EFFECTS LINE PRODUCER FOR PRIME FOCUS
Vikas Gandhi
VISUAL EFFECTS ASSISTANT PRODUCER FOR DARLOW SMITHSON PRODUCTIONS
Andrew Ryder
ONLINE EDITOR
Alan Jones
COLORIST
Blair Wallace
AUDIO MIX
Danny Finn
PROGRAM ADVISORS
Jim Bell David Grinspoon
ARCHIVE RESEARCH
Paul Gardner
James Labous
RESEARCH
Eloisa Noble
Faran Ismailpour
PRODUCTION COORDINATOR
Julia Speed
LINE PRODUCER
Ann Hampsey
ARCHIVAL MATERIAL
ASI
ASU
BBC Motion Gallery
Caltech
Carnegie Institution of Washington
Cassini Radar Team
Cornell University
ESA
ESO
Footage Vault
Gemini Observatory/AURA
Harvard University
HiRISE Imaging Team
Honeybee Robotics
Hubble
JAXA/Hayabusa Dome Movie Production Committee
JHU APL
Kennedy Space Center
NASA
NASA/Goddard Space Flight Center
NASA/JPL
Space Science Institute
Texas A&M University
The Institute for Solar Physics
University of Arizona
University of Rome
USGS
Washington University in St. Louis
SPECIAL THANKS
Southwest Research Institute
Caltech
Chris Abbas
David Chapman
Richard Kraus
Sarah Stewart
W. M. Keck Observatory
Harvard University
McGill University
Jacqueline Goordial
Lyle Whyte

FOR DARLOW SMITHSON PRODUCTIONS

DIRECTOR OF OPERATIONS
Ulla Streib
EXECUTIVE PRODUCER
Ben Bowie
NOVA SERIES GRAPHICS
yU + co.
NOVA THEME MUSIC
Walter Werzowa
John Luker
Musikvergnuegen, Inc.
ADDITIONAL NOVA THEME MUSIC
Ray Loring
Rob Morsberger
POST PRODUCTION ONLINE EDITOR
Spencer Gentry
CLOSED CAPTIONING
The Caption Center
MARKETING AND PUBLICITY
Karen Laverty
PUBLICITY
Eileen Campion
Victoria Louie
SENIOR RESEARCHER
Kate Becker
NOVA ADMINISTRATOR
Kristen Sommerhalter
PRODUCTION COORDINATOR
Linda Callahan
PARALEGAL
Sarah Erlandson
TALENT RELATIONS
Scott Kardel, Esq.
Janice Flood
LEGAL COUNSEL
Susan Rosen
DIGITAL PROJECTS MANAGER
Kristine Allington
DIRECTOR OF NEW MEDIA
Lauren Aguirre
ASSOCIATE PRODUCER
POST PRODUCTION Patrick Carey
POST PRODUCTION EDITOR
Rebecca Nieto
POST PRODUCTION MANAGER
Nathan Gunner
COMPLIANCE MANAGER
Linzy Emery
DEVELOPMENT PRODUCERS
Pamela Rosenstein David Condon
SUPERVISING PRODUCER
Stephen Sweigart
BUSINESS AND PRODUCTION MANAGER
Jonathan Loewald
SENIOR PRODUCER AND PROJECT DIRECTOR
Lisa Mirowitz
COORDINATING PRODUCER
Laurie Cahalane
SENIOR SCIENCE EDITOR
Evan Hadingham
SENIOR SERIES PRODUCER
Melanie Wallace
EXECUTIVE PRODUCER
Howard Swartz
MANAGING DIRECTOR
Alan Ritsko
SENIOR EXECUTIVE PRODUCER
Paula S. Apsell

A NOVA Production by Darlow Smithson Productions

© 2011 WGBH Educational Foundation All rights reserved

This material is based on work supported by National Aeronautics and Space Administration, Langley Research Center under the Research Cooperative Agreement No. NNL09AA00A awarded to the National Institute of Aerospace. Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of National Aeronautics and Space Administration, Langley Research Center or the National Institute of Aerospace.

FINDING LIFE BEYOND EARTH: MOONS AND BEYOND

Written, Produced and Directed by
Oliver Twinch

Produced in cooperation with NASA and the National Institute of Aerospace

ASSISTANT PRODUCERS
Alexis Burke
Dominic Aston
EDITED BY
Mairin O’Faolain
Jason Savage
Nigel Barker
CAMERA
Jonathan Dacey
NARRATED BY
Jay O. Sanders
SOUND RECORDISTS
Percy Urgena
Gregg Hinnen
Haven McKinney
Pandora Kronenburg
MUSIC
Universal Audio Network
VISUAL EFFECTS
Prime Focus
VISUAL EFFECTS SUPERVISOR FOR PRIME FOCUS
Simon Clarke
VISUAL EFFECTS LINE PRODUCER FOR PRIME FOCUS
Vikas Gandhi
VISUAL EFFECTS ASSISTANT PRODUCER FOR DARLOW SMITHSON PRODUCTIONS
Andrew Ryder
ONLINE EDITOR
Alan Jones
COLORIST
Blair Wallace
AUDIO MIX
Danny Finn
PROGRAM ADVISORS
Jim Bell
David Grinspoon
ARCHIVE RESEARCH
Paul Gardner
James Labous
RESEARCH
Eloisa Noble
Faran Ismailpour
PRODUCTION COORDINATOR
Julia Speed
LINE PRODUCER
Ann Hampsey
ARCHIVAL MATERIAL
Artbeats
BBC Motion Gallery
Corbis
Getty
Joseph Resing/NOAA
Footage Vault
Woods Hole Oceanographic Institution
NASA
NASA/JPL
Caltech
NASA/Goddard Space Flight Center
Southwest Research Institute
Eastbay Astronomical Society
Cassini Radar Team
ESA
Hubble
ASI
ESO
Gemini Observatory/AURA
Max-Planck-Institute for Astronomy
Rice University
STScI
University of Arizona
DLR
ASU
JHU APL
GSFC
Space Science Institute
Universities Space Research Association
Lunar & Planetary Institute
University of Colorado
USGS
NCSA/MSU/UC San Diego
Swedish Solar Telescope / L. Rouppe van der Voort (University of Oslo)
The Institute for Solar Physics
Hawaii Institute of Geophysics and Planetology
SPECIAL THANKS
YMCA Snow Mountain Ranch
Space Telescope Science Institute
Chris Abbas
Emily Lakdawalla
Charles Fisher
Penn State University
Linda Amaral Zettler
Marine Biological Laboratory

FOR DARLOW SMITHSON PRODUCTIONS

DIRECTOR OF OPERATIONS
Ulla Streib
EXECUTIVE PRODUCER
Ben Bowie
NOVA SERIES GRAPHICS
yU + co.
NOVA THEME MUSIC
Walter Werzowa
John Luker
Musikvergnuegen, Inc.
ADDITIONAL NOVA THEME MUSIC
Ray Loring
Rob Morsberger
POST PRODUCTION ONLINE EDITOR
Spencer Gentry
CLOSED CAPTIONING
The Caption Center
MARKETING AND PUBLICITY
Karen Laverty
PUBLICITY
Eileen Campion
Victoria Louie
SENIOR RESEARCHER
Kate Becker
NOVA ADMINISTRATOR
Kristen Sommerhalter
PRODUCTION COORDINATOR
Linda Callahan
PARALEGAL
Sarah Erlandson
TALENT RELATIONS
Scott Kardel, Esq.
Janice Flood
LEGAL COUNSEL
Susan Rosen
DIGITAL PROJECTS MANAGER
Kristine Allington
DIRECTOR OF NEW MEDIA
Lauren Aguirre
ASSOCIATE PRODUCER POST PRODUCTION
Patrick Carey
POST PRODUCTION EDITOR
Rebecca Nieto
POST PRODUCTION MANAGER
Nathan Gunner
COMPLIANCE MANAGER
Linzy Emery
DEVELOPMENT PRODUCERS
Pamela Rosenstein
David Condon
SUPERVISING PRODUCER
Stephen Sweigart
BUSINESS AND PRODUCTION MANAGER
Jonathan Loewald
SENIOR PRODUCER AND PROJECT DIRECTOR
Lisa Mirowitz
COORDINATING PRODUCER
Laurie Cahalane
SENIOR SCIENCE EDITOR
Evan Hadingham
SENIOR SERIES PRODUCER
Melanie Wallace
EXECUTIVE PRODUCER
Howard Swartz
MANAGING DIRECTOR
Alan Ritsko
SENIOR EXECUTIVE PRODUCER
Paula S. Apsell

A NOVA Production by Darlow Smithson Productions

© 2011 WGBH Educational Foundation All rights reserved

This material is based on work supported by National Aeronautics and Space Administration, Langley Research Center under the Research Cooperative Agreement No. NNL09AA00A awarded to the National Institute of Aerospace. Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of National Aeronautics and Space Administration, Langley Research Center or the National Institute of Aerospace.

IMAGE:

Image credit: Still from "Finding Life Beyond Earth" (Enceladus)
© WGBH Educational Foundation 2014

This is an excerpt from the NOVA program "Finding Life Beyond Earth."

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