From: Ron Baalke
Sent: Wednesday, September 16, 1998 8:53 PM
Subject: [ASTRO] Los Alamos Receives NASA Funding To Test Critical Instrument Components For Possible Use On Future Europa Mission
Public Affairs Office (PAO)
Los Alamos National Laboratory
CONTACT: Ternel Martinez, 505-665-7778 (98-136)
Lab receives NASA funding to test critical instrument components for
possible use on future Europa mission
LOS ALAMOS, N.M., Sept. 16, 1998 -- Los Alamos National Laboratory scientists recently received a $120,000 grant from NASA to use Laboratory space instrument design and manufacturing expertise and test critical components of an instrument that may lead to a final product for use on a future mission to the Jupiter moon Europa.
Concurrently, three Los Alamos researchers are part of a 17-member
international team working on a feasibility study for NASA to determine the
technical requirements for an instrument to study the moon's icy surface.
The preliminary report is due Nov. 1.
Called the Ice Penetrating Radar, the instrument would use a three-antenna
array that sends millions of radar signals at different frequencies to map
out the thickness of Europa's ice surface and detect, if present, a
subsurface Europan ocean. The IPR also would characterize Europa's ice
A liquid ocean is the most important ingredient in the development and
sustenance of life; detecting and characterizing Europa's oceans, if
present, are an integral part of scientists' search for evidence of life in
the solar system.
"If we can confirm the existence of a water ocean on Europa, it would be the
only ocean known to exist in our solar system outside of Earth's," said Brad
Edwards of Los Alamos' Space and Remote Sensing Sciences Group. Edwards also is part of the 17-member Instrument Definition Team, which includes researchers from around the world.
Because ice is transparent to a large range of radar signals, the IPR will
be able to record waves reflected off the top layer of ice and the ice-water
interface, ultimately converting them into three-dimensional images.
"We think the ice crust surface could be as deep as 100 kilometers, but data
we received from the Galileo spacecraft indicate that the ice could be as
thin as hundreds of meters," explained Edwards. Photos transmitted by the
Galileo spacecraft in 1994 presented the first evidence of the possible
existence of liquid water on Europa.
"If a water ocean does exist on Europa, the IPR can map thin areas of the
ice surface for future lander missions to Europa to sample the water for
signs of life," said Edwards.
Edwards said the Instrument Definition Team currently is studying many
things, including how to distinguish the different radar reflection signals
returned by rocks, cracks in the ice, salty and nonsalty ice, and other
conditions on the moon's surface. Another obstacle is making sure the IPR
survives Jupiter's intense radiation that surrounds Europa, he added.
"The radiation around Europa measures about 25 megarads per month. That's
enough radiation to fry a desktop computer in about five minutes," he said.
Still another important consideration is determining just how much power the
IPR will need in order to transmit and receive its radar signals and the
kinds of antennas that need to be used, said Xuan-Min Shao of Los Alamos'
Space and Atmospheric Sciences Group and fellow IDT member. Shao said he
hopes to begin testing the IPR prototype's antennas within the next couple
of months. The testing will take place at Los Alamos.
Shao said the instrument's weight is another major factor in designing and
building the prototype. "We think the Ice Penetrating Radar should weigh no
more than eight kilograms," he said, or about 17 pounds.
The final draft design for the IPR is scheduled to be submitted to NASA
sometime in March 1999, said Edwards. At that time, NASA will put out an
announcement for opportunities for the Europa mission, scheduled for launch
sometime in 2004. It would take anywhere from five to seven years for the
instruments to reach Europa, after which time measurements would be taken
for about a month.
The IPR is one of a suite of instruments -- called a strawman's payload --
that NASA currently is considering sending to Europa, the other instruments
being an optical camera, transponder and laser altimeter. The IPR is the
primary instrument; the laser altimeter would be used to measure the tidal
bulge of Europa's surface caused by Jupiter's tremendous gravitational pull
on the moon. "The laser altimeter will measure the moon's tides. If they're
small, then we'll know that there's little or no water underneath the
surface," said Edwards.
Shao said although it is conceivable that NASA may choose an instrument
suite that does not include the IPR for the Europa mission, because the IPR
is one of only a few instruments that can both measure Europa's ice surface
depth and characterize its structure, there is a good chance that it will
remain part of the suite that ultimately makes the 400-million-mile trek.
Los Alamos National Laboratory is operated by the University of California
for the U.S. Department of Energy.