Lesson 4 of 5 · A network between missions
A network between missions
5 minute lesson · 3 checks along the way
Your goal for this lessonExplain how a relay can connect missions without erasing their separate identities.
In this lesson 3 sections · 3 checks
Using archive links & definitions
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Read & understand
An international communications test
In November 2021, ESA’s Mars Express received data sent by Zhurong and relayed it to Earth for the Chinese team. The test used a compatible receiving path even though the normal two-way greeting sequence was not available between the two radios. This was a specific demonstrated operation, not proof of universal compatibility.
Check 1 of 3
10 pointsUse the reading above. You can try again without losing points.
Read & understand
Interfaces include timing
A fictional relay has a suitable receiver but passes overhead while the rover is silent. Compatible frequencies alone would not deliver a packet. The partners must coordinate visibility, transmission times, data formats and delivery to the intended ground team. Test results should identify which configuration actually worked.
Mars Express HRSC imagery of eastern Arabia Terra, acquired on October 26, 2009. It illustrates the ESA orbiter’s science work, not Zhurong’s 2021 relay test. Display image resized and compressed.
Look closely
How can one orbiter contribute to both science and another mission’s communications?
See what to notice
Different instruments and scheduled operations can support those roles; each claimed result still needs its own evidence.
Check 2 of 3
10 pointsUse the reading above. You can try again without losing points.
Read & understand
Credit each contribution
Mars Express remained an ESA mission and Zhurong remained part of China’s Tianwen-1 mission. Cooperation connected their capabilities. The terrain image here comes from Mars Express in 2009, illustrating that spacecraft’s separate observing role; it does not depict or prove the 2021 relay test. One history can credit multiple participants without duplicating a mission under several flags.
Check 3 of 3
10 pointsUse the reading above. You can try again without losing points.
Put it together
Your lesson progress
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