I know that using the scan on the galaxy map will attract reaper attention, but is it also true for the planet part (where you launch the probe)? Basically do I have to rush this bit or can I take my time when finding all the loot?
Scanning planets does not attract Reaper attention. You can take as much time as you want.
You can even scan planets after Reapers start chasing you. Everything in the star system is frozen when you click "Enter Orbit".
8Do note that it doesn't freeze immediately. There is a little lag between hitting the button and everything freezing so if you don't give yourself enough space you can easily be killed after the scanning. Mar 21, 2012 at 21:29
Yeah, the lag is enough to get you killed when checking floating fuel wreckage. Stupid dumb fuel... Mar 21, 2012 at 21:40
The problem is that in order to scan a planet or debris field, the system itself now needs to be scanned for triggers first, which does attract Reaper attention according to the message displayed after first entering a system.