This
story was updated at 9:31 a.m. EST.
DARMSTADT. Germany -- Europe's Huygens descent
probe will deliver its promised data on Saturn's moon, Titan, despite the loss
of one of two communications lines with which the probe communicated with NASA's
Cassini Saturn orbiter, U.S. and European scientists said Jan. 15.
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Huygens Speaks!
To
hear Titan's winds click here.
For
Huygen's descent click
here.
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Revealing new images and sounds of the orange-tinted,
methane-rich Titan surface, the European Space Agency (ESA) said it would
nonetheless open an inquiry into how the communications glitch
occurred.
"It was an ESA responsibility," ESA Science Director
said at Huygens mission control here. "We should have redundancy at all levels
[of the mission], including the ability to send commands."
The communications failure occurred on Cassini, not
Huygens, and was caused by an error "as simple as throwing a switch to, 'On.' We
did not set the Cassini software to 'On' and it's our fault," said Jacques
Louet, head of science projects at ESA. "Space does not forgive stupid mistakes,
and we made a stupid mistake. I take full responsibility."
Louet said a Huygens Mission Operations Plan sent by
ESA to Cassini managers at NASA's Jet Propulsion Laboratory contained improperly
written and confusing information. "JPL executed the instructions we gave them,"
Louet said. "One lesson we hopefully will draw from this is that you need
independent reviews of all systems. It's a classic example of the most-simple
things escaping review because they are simple."
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Huygens image of Titan. Credits: ESA/NASA/University of Arizona
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Sleepless science
"I haven't slept in 30 hours and
we're working hard to process the data," said Martin Tomasko, principal investigator for Huygens' Descent
Imager/Spectral Radiometer (DISR), speaking alongside other Huygens science team
leaders during the briefing. "This
is the view that you'd have if you were standing on Titan."
Tomasko unveiled a color image of a
previously released view of Titan's rocky surface as caught by the DISR
instrument during Huygens' landing. The orange hue of Titan, he said, was
recorded by spectrometers aboard the instrument, he said.
Sounds generated from the
microphone and radar sensors of the Huygens Atmospheric Structure Instrument
(HASI) gave researchers a chance to hear the probe's its plunge through Titan's
atmosphere.
Droning winds can be heard in one
sound clip recorded by Huygens' microphone during descent. In another, radar
echoes rise in pitch and intensity as the Huygens gets closer to Titan's
surface.
"It was impossible to transmit the
entire soundtrack," said HASI principal investigator Marcello Fulchigoni, adding
that the sounds he released today were reconstructed from snippets by
researchers. "But we have the principal fragments of these
sounds."
The communications glitch will mean that
doppler wind data from Huygens will need to be pieced together from the many
ground telescopes that were trained on Huygens during its two and one-half-hour
descent to Titan's surface on Jan. 14.
But that data will be available given the global
response of radio astronomers to Huygens, said Leonid Gurvits, head of the team
that coordinated the 18 primary telescopes in Australia, China, Japan, the
United States and Europe. "We will get the same scientific result, it will just
take a little longer," Gurvits said.
Tomasko added that 350 images during descent and
continuing after Huygens' landing were received on the one working
communications channel -- half the crop that would have been harvested had both
lines been functioning.
"We do have
holes sin our panoramic mosaics," Tomasko said after showing one striking
panorama stitched together the night of Jan. 14-15 by science teams. But Tomasko
said the images that have been received will keep scientists working for months.
"Given time, we will be able to learn some very interesting things about this
mysterious world that has been veiled to our view."
SPACE.com Staff Writer Tariq Malik contributed to
this report from New York City.
Touchdown
on Titan: Huygens Probe Hits its Mark