The author's excellent 'powers of observation' [=ability to notice and pay close attention to things] are evident in the book's detailed descriptions.
The plants seem to have recovered from the disease, but they are still 'under observation'. [=someone is watching them carefully]
They're keeping him at the hospital 'for observation' [=so that doctors can watch him carefully] for another few days.
(..) Is this right? I just say whatever to the video log? Yeah, we gotta get in the habit of documenting everything. You know, what we see, what we feel. - It's all part of the science. - And good science is good observation. Plus it'll help to keep you sane for the next six years. All right. Whatever. (..)2009 Avatar