ESA Document - Emits - ESA

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HMM
Assessment Study
Report: CDF-20(A)
February 2004
page 22 of 422
1. How far can safety requirements be fulfilled? What is the risk level that can be
accepted without hampering the mission feasibility?
2. What is the impact of radiation protection on the mission?
3. Which is the most appropriate approach to counter microgravity effects on the human
body? Is there any showstopper linked to microgravity exposure over a long period of
time?
4. What is the optimal compromise between mission duration (impact in e.g.
consumable and radiation protection mass) and ∆V (impact in e.g propellant mass)?
5. What is the optimal time-sharing between time spent around Mars and time spent in
interplanetary transfer, and what is the impact on mass?
6. What are the mass critical components and what are the design possibilities to reduce
the impact of these components on the mission feasibility?
7. Which are technologies worth investigating for this mission, meaning that their
implementation will result in significant benefits when compared to the “mission
case”?
8. What is the best assembly strategy for the vehicle in LEO?
The mission “case” has been defined according to the following criteria:
• Capability to perform quantitative assessments in a reliable way. This leads to select
technologies known and relatively mature even if not the most mass effective for the
overall mission.
• Mass effectiveness sought in trajectory and architecture definition (e.g. type of
trajectory, surface stay duration, number of vehicles, etc.). Therefore, an effort to
“optimise” the mission remaining within the limits of existing technologies has been
done.
• Possibility to extend the results to more generic/advanced missions.
2.2 Overall mission requirements and constraints
The requirements for the mission “case” have also been defined taking into account the most
general set possible with emphasis on physiology requirements, safety requirements and
planetary protection (common to all missions).
Specific requirements on functions and operations to be performed on the Martian surface and
during the whole mission have been reduced to a minimum to have a simple first design point as
a basis for future sensitivity analysis.
2.2.1 Mission Objectives
The following mission objectives for the design case to be analysed in this study were agreed by
a group of planetary exploration experts at the second Aurora Working Meeting:
• Land a crew of humans on Mars around 2030 and return them safely, ensuring planetary
protection for both Earth and Mars
• Demonstrate human capabilities needed to support a human presence on Mars
• Perform exploration and expand scientific knowledge taking maximum advantage of
human presence including sample selection
• Assess suitability of Mars for longterm human presence (habitability, resources
availability, engineering constraints)