[Defender2]

Yes, The F-102 as the F-101B/F and F-106A/B were equipped with an Infrared seeker device which could be tuned so sensitive as to track a lit cigarette from over 10,000 ft.
They F-102s'(during Operation Stovepipe) would go out at night and use their IR seekers finding enemy encampments at night sometimes using their rockets and IR homing missiles against them.

[CholeraJoe]

What won't they think of next? I expect if the USAF had IR seekers that sensitive in Vietnam, that the ones they have now can track a mouse's body heat from Low Earth Orbit.