The Ad Astra Rocket Company is an American rocket propulsion company dedicated to the development and sales of advanced plasma rocket propulsion technology. Located in Webster, Texas, several miles from NASA's Johnson Space Center, the company was incorporated on January 14, 2005. The President and CEO of Ad Astra Rocket Company is retired astronaut, Dr. Franklin Ramón Chang-Díaz. The company builds Engines on Chang-Diaz's concept of the Variable Specific Impulse Magnetoplasma Rocket, known by its acronym VASIMR. The VASIMR is used to achieve several advantages over other rocket designs, including lunar cargo transport, in-space refueling, and ultra-high speeds for distant space missions.