内容简介：Our ship, the space-flyer, Planetara, whose home port was Greater New York, carried mail and passenger traffic to and from both Venus and Mars. Of astronomical necessity, our flights were irregular. The spring of 2070, with both planets close to the Earth, we were making two complete round trips. We had just arrived in Greater New York, one May evening, from Grebhar, Venus Free State. With only five hours in port here, we were departing the same night at the zero hour for Ferrok-Shahn, capital of the Martian Union.