Conversation so far:
What is Columbia Hills?
Spirit reached the first of many targets at the base of the Columbia Hills called West Spur.
What happened after this?
Hank's Hollow was studied for 23 sols.
Why is this significant?
it contains hematite.
This kind of rock can be built in connection with water.

Question: What did the Spirit do?
Self-contained rewrite: What did the Spirit do after reaching West Spur and Hank's Hollow?