Thanks to a common spacecraft architecture and use of standardized mission control software, the spacecraft controllers -- the ESA calls them "spacecons" -- provide support to both missions, thereby reducing costs and improving efficiency. A spacon from either team can operate both their own and the other mission, uploading commands and monitoring routine spacecraft operations for both, the ESA said.
"The biggest advantages have come in closer cooperation between the teams -- there is better knowledge sharing and communications, as well as a bigger pool of cross-trained spacons," said Peter Wright, an ESA spacecraft analyst for Mars Express.
The ESA said the commonality enabled it to launch the missions to widely differing destinations on a budget that would otherwise have been much higher.
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