Launch Option 3: Space Shuttle and Ariane

Using one Space Shuttle launch and an Ariane 5 cuts down launch costs even more than the Titan Option, and uses launchers of multiple nations (for an international project). The Ariane 5 launch saves almost $300 M over the baseline plan of two Shuttles, with a mere $105 M for the AR5. The Ariane family is noted for its low cost and reliability, and the Ariane 5 is likely to be man-rated. The AR5 is also able to carry cryogenics and has the same size payload shroud as the Space Shuttle. There is still no need for an orbital assembly fixture with the Shuttle involved.

Although the price is down to $505 M, there is insufficient payload for the Reference Mission. An Ariane 44P, with a cost of $70 M and a payload of 17,000 lbs (7,700 kg) would be required to boost the payload into the range required. This raises costs to $575 M, but this is still better than the $800 M for the Space Shuttle Option. There is also the added logistical costs of moving hardware to South America for launch on the Ariane.

The Ariane 5 will have a payload of 42,000 lbs (19,000 kg), and the Space Shuttle has a payload of 55,000 lbs (25,000 kg) [possibly being upgraded to some 62,000 lbs (28,000 kg)]. With an Ariane 44P, this gives a total capacity of 114,000 - 121,000 lbs (52,000 - 55,000 kg).

Launcher	Payload	Cost
Shuttle + Ariane 5 + Ariane 44P	114,000 lbs (52,000 kg)	$575 M
Shuttle (upgrade) + Ariane 5 + Ariane 44P	121,000 lbs (55,000 kg)	$575 M

This is probably the preferable Space Shuttle option, as it provides two man-rated launches, albeit with a third small launch. It is more expensive than the less capable Proton option, but it is still cheap if a Shuttle is needed.