Martian Cylinder

About
The Martian Cylinders were the transports used by the Martians to reach Earth. From Mars, the cylinders were fired (or launched) at Earth and reached it in ten Earth months. In all, ten cylinders were fired during the Invasion. No reason for why the shots ceased after just ten were ever given, but three theories have been forwarded:
 * 1) The exhaust gasses from the gun/magnetic accelerator on Mars greatly polluted its atmosphere, causing greater-than-expected inconvenience.
 * 2) The gun/hydrogen accelerator itself was badly damaged and rendered unusable.
 * 3) The first ten were a reconnaissance team, and that if they didn't report back the invasion was called off.

Appearance
The Martian Cylinders are the large futuristic-like gray transports.