Why Xichang launches synchronous satellites to save energy than Jiuquan?

A synchronous satellite is a satellite that flies over the equator. The rocket will launch the satellite over the equator. Xichang is closer to the equator than Jiuquan, so it saves energy. This is one reason.

Second, first of all, you should know one thing: When we watched the launch of Shenzhou 5 Shenzhou VI, I wonder if you noticed it. After the rocket rose to a certain height, the commander issued an order: the rocket program turned. It all turns to the east. Because the earth turns from west to east, we can use the initial speed of the earth to launch rockets to the east, saving energy. The angular velocity of autobiography is the same everywhere on the earth. The closer to the equator, the larger the radius.

Generally speaking, there are two reasons.