Congress has passed and sent to President Donald Trump’s desk a NASA Authorization Bill that, for the first time in a long time, mandates that the space agency conduct a long-term program of space exploration with Mars and “other destinations” as goals. The bill also mandates the Orion deep space exploration vehicle and the heavy lift Space Launch System as key components of that effort.

Verbiage is included for NASA to seek international, academic, and commercial partners to explore space.

The authorization bill strikes the right balance between focus and flexibility. The former consists on the directive for NASA to land humans on the planet Mars. The latter allows for other destinations, both along the way and in parallel. The language of the bill does not mention lunar surface operations, preferring “cis-lunar space” as a stepping stone to Mars. The bill also suggests that the Asteroid Redirect Mission does not have much support and advises NASA to develop another mission that would test solar electric propulsion technology.

Trump is likely to sign the bill into law, which raises the question of what happens next. The new NASA administrator will have to develop a “road map” for space exploration that focuses on Mars. How that mandate will be integrated into a likely “Moon First” strategy will be interesting to see. It is entirely possible if and when Trump directs NASA to return to the moon, Congress may have to amend the authorization bill to explicitly accommodate that destination.

The moon would not, strictly speaking, violate the Mars focus of the bill so long as going back to the lunar surface would support to the ultimate goal. Water at the lunar poles could be refined into rocket fuel to make the moon a refueling stop for deep space operations.

The lunar surface would be used to test technologies such as habitats that would be applicable for Mars surface operations.

In any case, the next step will be President Trump’s, with the election of a NASA administrator, a space agency budget proposal, and a direction for future space exploration activities. The authorization bill is but one small step in the process of reinvigorating NASA and its space exploration activities.