"We hope to find a big piece of this object that survived the impact because then we can tell if it's a rock or technological gadget." He's just leaving the do

"We hope to find a big piece of this object that survived the impact because then we can tell if it's a rock or technological gadget." He's just leaving the door open. It's a bit intentional, as opposed to collecting evidence and seeing what it says. There's an assumption that a technological gadget was created by aliens and not humans. Or some god.