Researcher and Researched

“Aliens exist! And they’re watching us right now!” Jordan exclaimed in horror as a long string of numbers appeared on his computer.
“Prove it.” His research partner Jim walked over, sceptical.
“I’ve detected their space station, just outside the solar system. See these results?” Jordan pointed to the computer.
“Why haven’t we detected it?”
“It’s invisible, emits no electromagnetic radiation or particles, or anything for that matter.”
“Then how did you detect it?” Jim still didn’t believe him.
But he never found out the answer, for at that moment a powerful death ray hit Earth, obliterating it immediately. For aliens do not like their subjects of research knowing of their existence.