Mars Direct

Introduction

In designing a mission to Mars, it is important that the plan be simple and cost effective yet be able to complete the mission requirements. One alternative that fits these criteria is known as the "Mars Direct" plan. In Mars Direct there will be two launches involved. The first will deliver an unfueled and unmanned Earth Return Vehicle (ERV) to the Martian surface. It will then manufacture methane/oxygen propellant out of resources found on Mars. The second launch will deliver the crew to the planet where they will explore and experiment for 1.5 years before returning to Earth in the ERV.

Key points in keeping a Space Exploration Initiative (SEI) mission to Mars low-cost but effective include the following:

1. The mission should not depend upon and LEO stations as it is costly to build and maintain such a station and difficult to repair.
2. To be highly effective, astronauts must have these three elements once they reach their destination: time, mobility, and power. Astronauts must have time to perform their experiments at their destination and explore the surface of Mars. Most Martian mission plans have about 1.5 years of flight time with only a few weeks on the surface. Mobility is needed for the exploration of the Martian surface and to perform experiments on the surface. On Mars, power can be produced using methane/oxygen or carbon monoxide/oxygen combinations. Rocket thrust for the propulsion in the return flight can be produced by using carbon dioxide propellant heated in a nuclear thermal rocket engine.