1.   Another popular class is space exploration, in which students learn about orbital mechanics, gravity and aerodynamics while studying about the solar system.

2.   After what appeared to be an unnecessary and quite minor correction to it, we asked one of the flight directors why they were fooling with the orbital mechanics.

3.   It is a return to his old intellectual passion for the science of orbital mechanics.

4.   The trouble with commercial satellite projects has often come when the backers incorrectly assume that aerospace engineering and orbital mechanics are the hard part.