Landing on Titan: The New Movies

LANDING ON TITAN: THE NEW MOVIES
(From Lori Stiles, University Communications, 520-621-1877)

- Thursday, May 04, 2006

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Movies in Beta format -
Contact University Communications, 520-621-1877

Contact Information
Erich Karkoschka 520-621-3994
Chuck See 520-621-1097
Martin Tomasko 520-621-6969

Related Web sites - listed at end of release
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Scientists at the University of Arizona Lunar and Planetary Laboratory
(LPL) have made two new movies of the Huygens probe's landing on
Saturn's
giant moon, Titan, on Jan. 14, 2005.

The movies were made from images taken by Huygens' Descent
Imager/Spectral
Radiometer (DISR) during its 147-minute plunge through Titan's thick
orange-brown atmosphere to a soft sandy riverbed. They are the most
realistic way yet to experience the far-out-world landing.

The movies are being released today on
http://www.lpl.arizona.edu/DISR/, on
http://saturn.esa.int, on http://saturn.jpl.nasa.gov and
http://www.nasa.gov/cassini

DISR was developed with NASA funding by UA and Lockheed Martin
researchers
on a team headed by LPL Research Professor Martin Tomasko. The European
Space Agency (ESA) Huygens probe is part of the joint NASA, ESA and
Italian
Space Agency Cassini-Huygens mission to the Saturn system. The probe
landing
was the most distant touchdown ever made by a human-built spacecraft.

LPL senior staff scientist and DISR team member Erich Karkoschka
created
the new Huygens landing movie and the new DISR movie.

Scientists were extremely busy analyzing data for months after the
landing,
Karkoschka said. They didn't have a chance to give the public a good
overview of what was going on until later. "I hope the new movies help
to
put the different results into context," he said.

In the Huygens movie, "I wanted to show what the Huygens probe 'saw'
within
a few hours," Karkoschka said. "At first, the Huygens camera just saw
fog
over the distant surface. But after landing, the probe's camera could
resolve little grains of sand millions and millions times smaller than
Titan. A movie is a perfect medium to show such a huge change of
scale."

DISR team member Chuck See scripted this narrated movie, "The View from
Huygens on January 14, 2005," which runs 4 minutes 40 seconds. KUAT
radio
broadcaster David Harrington narrates. Another version is accompanied
by a
recording of Beethoven's Piano Concerto No. 4 performed by Debbie Hu of
Yelm, Wa.

For the second, more technical movie, Karkoschka shows DISR's 4-hour
operating life in less than five minutes, too. It takes some text to
follow
all the graphics and sidebar information that comes with this version.
Karkoschka's description of this movie is within the online story
posted at
http://uanews.org/science.

"DISR was a very complicated instrument," Karkoschka said. "It had to
be
programmed to take its 3,500 exposures in a way to get the most
science. It
had to decide where and when to take exposures."

DISR was designed when the best images showed Titan as a featureless,
hazy
disk. "We didn't know the dynamics of Titan's atmosphere very well, and
we
didn't know how fast Huygens would rotate and swing," Karkoschka said.
"It
was an extremely challenging programming task to make DISR work well
under
every imaginable condition."

A movie is ideal for showing how DISR worked.

For example, the first part of the movie shows how Titan looked to DISR
as
it acquired more and more images during the probe's descent. Each DISR
image
has a small field of view, and dozens of images were made into mosaics
of
the whole scene.

Karkoschka analyzed Huygens' speed, direction of motion, rotation and
swinging during descent. His DISR movie includes sidebar graphics that
show
such things as:
(Lower left corner) Huygens' trajectory views from the south,
a
scale bar for comparison to the height of Mount Everest, colored arrows
that
point to the sun and to the Cassini orbiter.
(Top left corner) A close-up view of the Huygens probe
highlighting large and unexpected parachute movements, and a scale bar
for
comparison to human height.
(Lower right corner) A compass that shows the changing
direction
of view as Huygens rotates, along with the relative positions of the
sun and
Cassini.
(Upper right corner) A clock that shows Universal Time, also
referred to as Greenwich Mean Time, on Jan. 14, 2005. Above the clock,
events are listed in Mission Time, which starts with the deployment of
the
first parachute.

A musical score comes with this movie, too. But it's definitely modern,
not
classical.

"There's so much information in the different displays that come with
this
movie that one can easily miss something important," Karkoschka said.
"Therefore, I added sound to track the most important features, because
the
ears hear all the sound no matter where you look."

Sounds from a left speaker trace Huygens' motion, with tones changing
with
rotational speed and the tilt of the parachute. There also are clicks
that
clock the rotational counter, as well as sounds for the probe's heat
shield
hitting Titan's atmosphere, parachute deployments, heat shield release,
jettison of the DISR cover and touch down.

Sounds from a right speaker go with DISR activity. There's a continuous
tone that represents the strength of Huygens' signal to Cassini. Then
there
are 13 different chimes - one for each of DISR's 13 different science
parts
- that keep time with flashing-white-dot exposure counters.

All parts of DISR worked together as programmed, Karkoschka said. It
was
pure harmony.

University of Arizona Lunar and Planetary Laboratory scientist Martin
Tomasko leads the DISR team. Team members are based throughout the
United
States and Europe, with the largest contributing groups from the UA in
the
United States, from the Max Planck Institute in Germany, and the Paris
Observatory in Meudon, France.

The Cassini-Huygens mission to Saturn and Titan is a joint mission of
NASA,
the European Space Agency (ESA) and the Italian Space Agency (ASI). ESA
supplied and manages the Huygens probe that descended to Titan's
surface
Jan. 14, 2005. NASA's Jet Propulsion Laboratory, a division of the
California Institute of Technology in Pasadena, manages the mission for
NASA's Science Mission Directorate in Washington, D.C. NASA funded the
Descent Imager-Spectral Radiometer, which was built by Lockheed Martin.
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Related Web links -
DISR- http://www.lpl.arizona.edu/DISR/
ESA - http://saturn.esa.int
JPL - http://saturn.jpl.nasa.gov
NASA - http://www.nasa.gov/cassini
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