Astronomers Track a Deep-Space Anomaly in NASA’s Pioneer 10 and 11 Missions

Astronomers Track a Deep-Space Anomaly in NASA’s Pioneer 10 and 11 Missions

When NASA’s Pioneer 10 and Pioneer 11 spacecraft passed about 20 astronomical units from the Sun, scientists noticed something strange: both probes seemed to experience an unexplained acceleration back toward the Solar System. Credit to : NASA Space News