Synchronous Satellites of Venus

Synchronous satellites of Venus have long been thought unstable, but we use Poincare's surface of section technique to show that synchronous quasi-satellites orbiting just outside Venus' Hill sphere are quite stable, at least for centuries. Such synchrosats always remain within a few degrees of Venus' equator, and drift very slowly in longitude. These synchrosats could be useful for continuous monitoring of points on Venus' surface, such as active landforms or long-lived landers.