Decades of meticulous investigation have revealed many features of the 1st Century BC Antikythera Mechanism, a portable planetarium that demonstrated the motion of celestial objects. But we must question researchers’ conclusion that the Mechanism incorrectly represented the orbit of Mars, in particular, by roughly 30 degrees during retrograde motion1.
This discrepancy seems anomalous in a sophisticated device that otherwise exhibited a much smaller range of error. So maybe there is some other explanation.
A new theory of the origin of the terrestrial planets—that Jupiter’s gravity pulled them inward from the outer solar system—solves longstanding scientific riddles and offers a rich agenda for further investigation.