Also, because of Reed Richards' Thing-Finderer...I mean, his Portable Energy-Detector.
Panels from Marvel Two-in-One Annual #7 (1982); script by Tom DeFalco; pencils by Ron Wilson; inks by Bob Camp, Mike Esposito, Frank Giacoia, Dan Green, Armando Gil, and Chic Stone; colors by George Roussos; letters by Jim Novak
Clearly an evolutionary and technological advance on Reed's Heat-Image Tracer, it picks up and analyzes not heat, but alien residue. So, like, stray hairs that fell off the Watcher's head (wait, perhaps a bad example), fabric shreds where Dominus stepped accidentally on his really dramatic albeit waaaaay-too-long cape, or the Silver Surfer's belly-button lint. Instantly Reed discovers that the alien being who kidnapped Ben Grimm has cosmic energy and power greater than Galactus and stranger than anything our puny Earth minds can conceive. So, Cosmic Paris Hilton, then.
Later, of course, Sue pointed out that they could just click on Ben's laptop to "Show My StarkPhone," which zeroed directly in on the Thing, allowing the Fantastic Four to rush directly to his side at the bar of the Yancy Street Grill. It was Monday night: 25¢ buffalo wings and buck-a-drafts, and Mavericks vs. Knicks on the big screen. Sometimes Ben just can't escape his "pals," not even for just one ferschluggin' night. Whatta revoltin' development.