Editing Mars Express (section)

=== Communications ===
The communications subsystem is composed of three antennas: A 1.6&nbsp;m diameter parabolic dish [[high-gain antenna]] and two omnidirectional antennas. The first one provide links (telecommands uplink and telemetry downlink) in both [[X-band]] (8.4&nbsp;GHz) and [[S-band]] (2.1&nbsp;GHz) and is used during nominal science phase around Mars. The low gain antennas are used during launch and early operations to Mars and for eventual contingencies once in orbit. Two Mars lander relay UHF antennas are mounted on the top face for communication with the ''Beagle 2'' or other landers, using a Melacom transceiver.<ref name="melacom">{{cite web |url=http://apps.qinetiq.com/perspectives/micro_news_article7.asp |title=QinetiQ to put Mars in the picture |archive-url=https://web.archive.org/web/20060831063330/http://apps.qinetiq.com/perspectives/micro_news_article7.asp |archive-date=August 31, 2006 |quote=Consisting of a lightweight bespoke transponder and transceiver weighing less than 650 grams, the system will provide the 10,000-kilometre UHF radio communications link between the ''Mars Express'' orbiter and Beagle-2 lander. |publisher=[[Qinetiq]] |access-date=March 29, 2016 }}</ref>

==== Earth stations ====
Although communications with Earth were originally scheduled to take place with the ESA 35-meter wide Ground Station in New Norcia (Australia) [[New Norcia Station]], the mission profile of progressive enhancement and science return flexibility have triggered the use of the ESA [[ESTRACK]] Ground Stations in [[Cebreros Station]], [[Madrid]], Spain and [[Malargüe Station]], [[Argentina]].

In addition, further agreements with NASA [[Deep Space Network]] have made possible the use of American stations for nominal mission planning, thus increasing complexity but with a clear positive impact in scientific returns.

This inter-agency cooperation has proven effective, flexible and enriching for both sides. On the technical side, it has been made possible (among other reasons) thanks to the adoption of both Agencies of the Standards for Space Communications defined in [[CCSDS]].