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In 1996, Simon Rowland conducted a cursory study of six options for launching and assembling the Artemis Project reference mission spacecraft, with the goal of determining the lowest-cost method of transporting the spacecraft and crew to low Earth orbit. The study examines only launch systems which are currently operational or under development, and contain a significant bias based on accepting undemonstrated cost and performance for the Ariane 5. However, the documents resulting from this study are useful because they show a general trend in launch costs and collect some data regarding the estimated costs and performance of these launchers.
From this limited evaluation, the lowest-cost option appears to be expendable boosters in conjunction with a simplified private transportation node in low Earth orbit. Initially, the transportation node would consist of the minimum equipment necessary to support assembly and servicing of the Lunar Transfer Vehicle and the landing stack. Later, a fuel depot might be added.
That's why our presentation of the current reference mission emphasizes use of a new, commercial service station in low Earth orbit. Note that the artwork shows Soyuz spacecraft used for launching the crew. This study did not consider the alternative of using expendable boosters for the heavy cargo and a Shuttle flight for personnel transportation.
For the first mission, the estimated cost of option 5 (Ariane-Proton combination using the International Space Station as a staging base), and option 4 (Shuttle-Proton combination) are nearly equal. An Ariane launch is required in conjunction with the Proton because SPACEHAB modules will not fit in a Proton's payload shroud.
This plan includes many inherent risks, which remain subjects for future study:
Here is Simon's summary of the resulting costs for each option. Note that all the cases examined show launch costs significantly lower than the $800 million assumed in the original reference mission study.
Assembly Platform | Option # | Launcher | Payload | Cost | Comments |
LEO Node | 6 | Ariane 5 + 2 Protons + 2 Soyuz | 137,000 lbs (67,000 kg) (Assembly node) | $275M + $150M for node | Apparently the lowest-cost option |
International Space Station | 5 | 2 Ariane 5's + 2 Protons + 2 Soyuz | 170,000 lbs (77,000 kg) | $380M | Boiloff, inclination mass penalties |
Shuttle | 4 | Shuttle (upgrade) + 2 Protons | 168,000 lbs (66,000 kg) | $520M | Requires new Proton launch facilities, which are not included in the cost estimate |
Shuttle | 3 | Shuttle (upgrade) + Ariane 5 + Ariane 44P | 121,000 lbs (55,000 kg) | $575M | Most flexible Shuttle option |
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