|
Posted by baalke on November 20, 2006, 12:15 am
Please log in for more thread options
http://www.jpl.nasa.gov/news/features.cfm?feature=1230
NASA's Newest Mars Orbiter Passes Communications Relay
Media contact: Guy Webster/JPL, (818) 354-6278
November 17, 2006
An orbiting NASA spacecraft just starting to study Mars with six
science
instruments has successfully tested another key part of its payload, a
versatile radio for relaying communications with robots on the surface
of Mars.
During its first relay test since reaching Mars in March, the Mars
Reconnaissance Orbiter used this radio payload, called Electra, in a
two-way link with NASA's Mars Exploration Rover Spirit. The orbiter has
dual roles as a science mission and a telecommunications satellite. It
will support communications between Earth and future Mars surface
missions, such as the 2007 Phoenix Mars Lander and 2009 Mars Science
Laboratory.
"The successful test establishes Mars Reconnaissance Orbiter as a key
element of our Mars telecommunications infrastructure," said Chad
Edwards, chief telecommunications engineer of the Mars Network Office
at
NASA's Jet Propulsion Laboratory, Pasadena, Calif. "With its Electra
relay payload, this orbiter will play a critical role in providing
robust, high-bandwidth communications links for our future landers
later
this decade and into the next. It will increase the science return from
these missions and enhance our virtual presence on the Martian
surface."
JPL's Jim Graf, project manager for Mars Reconnaissance Orbiter, said,
"Our primary science phase started Nov. 7, and this successful Electra
test shows we're also in good shape for the following phase, the relay
phase of the mission. Both phases will make good use of our orbiter's
capability for sending data to Earth at up to 10 times the rate of any
previous Mars mission."
Using Mars orbiters as radio relays to increase data return from rovers
and other landers reduces the mass and power the surface spacecraft
need
for communications. To build the relay network cost-effectively, NASA
includes a relay communications payload on each of its science
orbiters.
Mars Global Surveyor, at Mars since 1997, and Mars Odyssey, there since
2001, established a relay capacity that the twin rovers Spirit and
Opportunity have used extensively since their 2004 landings. More than
96 percent of the data returned from the rovers has come to Earth via
energy-efficient relay through those two orbiters, at much higher data
rates than the rovers can achieve on their direct links to Earth.
The Electra package on Mars Reconnaissance Orbiter, like the relay
radios on Global Surveyor and Odyssey, uses an ultra-high-frequency
(UHF) portion of the radio spectrum. In addition to its relay function,
Electra can also be used by surface missions, or by future spacecraft
approaching Mars, to determine their positions with precision and to
synchronize their clocks.
During last week's tests, Electra initiated a relay session by hailing
the Spirit rover. Spirit responded with its own relay radio, and the
two
spacecraft established a link at 8 kilobits per second on the forward
link from Mars Reconnaissance Orbiter to Spirit and 128 kilobits per
second from Spirit back to the orbiter. Both radios used a
communications standard called the Proximity-1 Space Link Protocol,
established by the international Consultative Committee for Space Data
Systems for ensuring compatible and gap-free communications on such
relay links.
During the four-minute session, the orbiter delivered five commands to
the rover, and the rover sent up 30 megabits of information, which the
orbiter subsequently transmitted to Earth for delivery to the rover's
operations team at JPL.
Nearly all of the signal-processing capabilities of Electra can be
reprogrammed in flight, giving it more flexibility than earlier
spacecraft relay radios.
"Electra is NASA's first software-defined radio sent to deep space,"
said JPL's Tom Jedrey, manager for the Electra payload. "From the
ground, we can change the fundamentals of its signal processing
whenever
that is helpful. This means it will be able to accommodate new
communication protocols and signal-processing methods over the course
of
the Mars Reconnaissance Orbiter's operational life."
Additional information about Mars Reconnaissance Orbiter is available
online at http://www.nasa.gov/mro . The mission is managed by JPL, a
division of the California Institute of Technology in Pasadena, for the
NASA Science Mission Directorate, Washington. Lockheed Martin Space
Systems, Denver, is the prime contractor for the project and built the
spacecraft.
|
|
Posted by Jan Panteltje on November 20, 2006, 5:55 am
Please log in for more thread options
On a sunny day (19 Nov 2006 21:15:54 -0800) it happened baalke@earthlink.net
>Additional information about Mars Reconnaissance Orbiter is available
>online at http://www.nasa.gov/mro .
This is a nice one:
http://www.nasa.gov/mission_pages/MRO/multimedia/pia01922.html
|
| Similar Threads | Posted | | Mars Reconnaissance Orbiter Tweaks Course, Passes Halfway Point | November 21, 2005, 11:13 am |
| Newest Phobos Images from Mars Orbit | April 13, 2008, 7:53 pm |
| NASA's New Mars Orbiter Returns Test Images | March 24, 2006, 3:45 pm |
| Re: NASA's New Mars Orbiter Returns Test Images | April 18, 2006, 10:45 pm |
| Re: NASA's New Mars Orbiter Returns Test Images | April 19, 2006, 11:34 am |
| Re: NASA's New Mars Orbiter Returns Test Images | April 19, 2006, 5:01 pm |
| Re: NASA's New Mars Orbiter Returns Test Images | April 19, 2006, 5:01 pm |
| Re: NASA's New Mars Orbiter Returns Test Images | April 19, 2006, 11:13 pm |
| Re: NASA's New Mars Orbiter Returns Test Images | April 19, 2006, 5:01 pm |
| Re: NASA's New Mars Orbiter Returns Test Images | April 19, 2006, 11:15 pm |
|
XML Sitemap