How about busting out the thermal imaging devices round the clock?

I was thinking that people who are motivated to find what goes on at Area 51 may follow this idea. I was thinking maybe it makes sense to bring thermal cameras or some other type of device related to thermal imaging to see what UFO is heading in or out of the base at night. Also the thermal provides (possibly) an image of the size and shape of any secret aircraft. And also, I believe the best way to get any image of any secret aircraft is to position yourself at the end of each runways, I don't mean get into the area and stand at the edge of the end of the runways, but putting yourself where the aircraft must descend or starting to land without having authorities arresting you. Good idea?

No, very bad idea.

You would never get to the runway for starters. You obviously underestimate the size and determination of the camodudes to keep people out of there.

The only publicly accessable place for viewing Area 51 is Tikaboo peak.

The public land around area 51 is loaded with motion sensors and detectors, hidden cameras, plus many surveilance items we know nothing about.

I'm not asking to infiltrate the place and put yourself near the runways, just observe any possible descending aircraft from the distance in the area where aircraft are starting to land in the direction of the runways. After all, any possible secret aircraft must descend a few thousand feet couple of miles away, before landing.

The problem is thermal imaging cameras commercially available to the general public cannot zoom far enough to watch Area 51. And even if you were close enough, you could not identify a stealth aircraft through a thermal cam, not that I know personally but I think it would only show as a blurry blob at best.

They are well aware of those technologies. Think about CADPAT or MARPAT uniforms that reduce infrared signature, or Ghillie suits used by snipers that are completely invisible to thermal cams.