[meteorite-list] NASA Radio on Europe's New Mars Orbiter Aces Relay Test

[Ron Baalke]

http://www.jpl.nasa.gov/news/news.php?feature=6685

NASA Radio on Europe's New Mars Orbiter Aces Relay Test
Jet Propulsion Laboratory
November 29, 2016

Data from each of the two rovers active on Mars reached Earth last week 
in the successful first relay test of a NASA radio aboard Europe's new 
Trace Gas Orbiter (TGO).

The transmissions from NASA rovers Opportunity and Curiosity, received 
by one of the twin Electra radios on the orbiter on Nov. 22, mark a strengthening 
of the international telecommunications network supporting Mars exploration. 
The orbiter's main radio for communications with Earth subsequently relayed 
onward to Earth the data received by Electra.

The European Space Agency's (ESA's) ExoMars/Trace Gas Orbiter reached 
Mars on Oct. 19, 2016. As planned, its initial orbit shape is highly elliptical, 
ranging from as far as 60,000 miles (98,000 kilometers) above the surface 
to less than 200 miles (less than 310 kilometers). Each loop takes 4.2 
days to complete.

Frequent use of TGO's relay capability to support Mars rover operations 
is planned to begin more than a year from now. That's after the orbiter 
finishes adjusting its orbit to a near-circular path about 250 miles (400 
kilometers) above Mars' surface. Meanwhile, four other active Mars orbiters 
also carry radios that can provide relay service for missions on the surface 
of Mars. The two active rovers routinely send data homeward via NASA orbiters 
Mars Odyssey and Mars Reconnaissance Orbiter (MRO).

"The arrival of ESA's Trace Gas Orbiter at Mars, with its NASA-provided 
Electra relay payload on board, represents a significant step forward 
in our Mars relay capabilities," said Chad Edwards, manager of the Mars 
Relay Network Office within the Mars Exploration Program at NASA's Jet 
Propulsion Laboratory, Pasadena, California. "In concert with our three 
existing NASA orbiters and ESA's earlier Mars Express orbiter, we now 
have a truly international Mars relay network that will greatly increase 
the amount of data that future Mars landers and rovers can return from 
the surface of the Red Planet."

NASA is on an ambitious journey to Mars that will include sending humans 
to the Red Planet. Current and future robotic spacecraft are leading the 
way and will prepare an infrastructure in advance for human missions.

The JPL-designed Electra radios include special features for relaying 
data from a rover or stationary lander to an orbiter passing overhead. 
Relay of information from Mars-surface craft to Mars orbiters, then from 
the Mars orbiters to Earth, enables receiving much more data from the 
surface missions than would be possible with a direct-to-Earth radio link 
from the rovers or landers.

"We already have almost 13 years' experience using ESA's Mars Express 
as an on-call backup for data relay from active Mars rovers, and TGO will 
greatly expand this to routine science-data relay," said Michel Denis, 
TGO flight director at ESA's European Space Operations Centre, Darmstadt, 
Germany. "In 2020, TGO will extend this relay support to ESA's ExoMars 
rover and the Russian Surface Platform, an important capability together 
with its science mission that enhances the international data network 
at Mars."

As an example of Electra capabilities, during a relay session between 
an Electra on the surface and one on an orbiter, the radios can maximize 
data volume by actively adjusting the data rate to be slower when the 
orbiter is near the horizon from the surface robot's perspective, faster 
when it is overhead.

Curiosity and Mars Reconnaissance Orbiter already use Electra technology 
to relay data. NASA's Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft, 
in orbit since 2014, also carries an Electra radio.

Due to improvements in the newest Electra radios and reduced interference 
levels, TGO's relay radios are expected to offer relay performance about 
double that of MRO's Electra.

TGO's main X-band radio uses a dish antenna 87 inches (2.2 meters) in 
diameter to communicate with Earth-based antenna networks operated by 
ESA, NASA and Russia.

JPL, a division of the California Institute of Technology in Pasadena, 
manages the Curiosity, Opportunity, MRO and Odyssey missions, and NASA's 
role in the ESA ExoMars program for the NASA Science Mission Directorate, 
Washington.

For more about ESA's ExoMars program, including TGO, visit:

http://exploration.esa.int/mars/

For more information about NASA's journey to Mars, visit:

https://www.nasa.gov/topics/journeytomars

News Media Contact
Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6278
guy.w.webster at jpl.nasa.gov

Dwayne Brown / Laurie Cantillo
NASA Headquarters, Washington
202-358-1726 / 202-358-1077
dwayne.c.brown at nasa.gov / laura.l.cantillo at nasa.gov

2016-305