Visible crew/equipment: When Picard, Data and Worf are on the planet, just a few shots after they leave the shuttle, Picard drives a sharp left curve. If you look at him in this shot, it is not Patrick Stewart sitting on the driver's seat, but his stuntman, who is not even wearing goggles. (00:12:45)
Trivia: Director Bryan Singer (X-Men among others) makes a cameo appearance on the bridge of the Enterprise. He's a non-speaking extra. When the Reman boarding party has beamed aboard and Riker and Worf leaves the Bridge to take care of the boarding party Singer is the officer who takes over Worf's tactical station. In the audio commentary on the DVD release Nemesis director Stuart Baird points out Bryan Singer's appearance and continues 'apparently he's a big fan of Star Trek'. (01:23:25)
Answer: Long range sensors can show the general location of specific ships (this is part of the reason Romulans and Klingons use cloaking devices). All Shinzon has to do is find a remote planet close enough to the Enterprise that would cause them to be the most prudent choice to investigate. It's definitely a gamble but not one that is made without calculation.
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