Both spacecraft make use of the US space agency's Tracking and Data Relay Satellite System (TDRSS) to speak to the ground and controllers do not want any conflicts.

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In April, China launched its first tracking data relay satellite to lessen its dependency on ground satellite control and relay stations.

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The data are sent from the orbiting outpost to NASA's Tracking and Data Relay Satellites, which relay it to the satellite reception dishes at NASA's White Sands Test Facility in New Mexico.

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