Persol said:
An object, includign air. Because of this visible wavelength lasers are visible on FLIR systems... they heat up the air.
Persol, that statement is only slightly true. Most visible wavelength lasars
are not powerful enough to heat up the air to any detectable amount over
large distances. If lasars were pointed at the Mexican plane that were
powerful enough to heat the air between the laser and the plane, they
would also have heated the plane and destroyed the eyes of the crew
who were looking out the windows for several minutes trying to see the
objects. They knew where to look and would have been looking right at the
lasers. Again, FLIR cameras detect the invisible infrared wavelength of
photons emitted by an electron excited by heat. If the atoms, and thus
the electrons, are heated too much, the energy and the wavelength of
the photons changes to the visible spectrum, first becoming red, visible
red light. The FLIR camera they used is designed to operate on the infrared
spectrum, detecting photons emitted from a cooler source. The returns they
picked up would have been warm, but not red hot. That is why the FLIR
camera they used can detect the infrared emissions from a warm jet engine, but not the very hot exhaust gasses from that same engine. It detects a
certain range of the electromagnetic spectrum, the infrared range. Even
your home remote control devices use infrared, but use the near-infrared
spectrum closest to visible light. The detector mounted in the TV or whatever, picks up this invisible light from your handheld remote control
to operate the TV. The handheld remote is not 'hot' and it does not heat
the air between it and the TV. It does generate infrared signals by 'slightly'
heating elements within the remote control. That is where infrared photons
they detected came from, warm objects, not 'hot' objects, and not just hot air.