Often, many people overlooked Luna's intelligence. She didn't work on the "right" sort of things, so that made her loony and obviously unintelligent. However, when Luna focused on something she accomplished quite a lot. She had good grades (in the classes she cared about), and she could name you any fact about "her" animals. Luna's research on her virus was taking shape as well. She was working alongside Hermione and Stephen, and they were all taking their own approaches. Stephen was mostly interested in the mist that had taken over the school, Hermione was interested in the virus itself - what had caused it and why? Whereas Luna was interested in patters, because she felt the world moved in cycles, and this was just another cycle.
With a smile, Luna bounded towards the professor. She wouldn't have picked up on Septima's nerves if her life depended on it. Why on earth would anyone be nervous to see her? "Afternoon Professor," Luna greeted cheerily. Luna was always too happy, even in grim situations she was fairly content and calm. This entire time stuck in Hogwarts she hadn't freaked out - it wasn't much different than a normal semester, after all.