Emissivity is supremely sensitive to the surface topography. It is seldom dominated by the intrinsic properties of the material. These apparent temperature differences could easily be the result of differences in surface weathering or dirt or differences in orientation of the tiny crystals of the various materials that make up granite. Another answer would come from an instrument that uses two different spectral bands to estimate temperature, as emissivity is less likely to be wavelength dependent, or better yet, contact measurements with a thermocouple on particular areas which seem to show anomalies.
I was thinking that rough granite would have a high emmisivity, I wonder if the tables I found refer to polished granite like in kitchens etc. , that said there seems to be sky reflections on one of the photos. Although on reflection (pun intended) for the image anomaly to be caused by reflection the heat mass would need to be quite significant, using what looks like a person in the image for scale a reflected heat source would need to be several meters high. The only other reflection possibility I can think of would be the sun? In any case would be easy to verify with different angle images.
The other possibility would be the presence of moisture due to different material or surface. If my understanding is correct a damp stone would hold the heat longer at night.
If the idea of a hidden passage were correct would it show up like this? Assume they took an image in the morning as the sun warmed the cool stone, blocks with nothing behind them would in theory warm up faster as they have no thermal heat sink behind them.
While you can get thermal lags like this, it seems unlikely in this case. If the hypothetical hidden passages were only a few centimeters from the surface they would definitely show such a signal under appropriate conditions. But a rock wall that thin would have been obvious to any number of other observation techniques that have been used in the past. If the passages are further from the surface the thermal signal will start to disappear for a couple of reasons. First the thermal time constant gets long relative to a day. Secondly, the passages need to be human scale, or else cave-ins or detections be other means would have occurred. But if human scale, lateral heat spreading tends to blur any signal.
That leaves you with theories only the ancient astronaut or crystal energy crowds could believe. Theories like "The materials of these rocks were engineered to have different thermal characteristics so that they could be detected once a sufficiently advanced civilization developed." And they predicted how far in the future that would occur so that the engineered rocks would be on the surface after the theft of the surfacing stones and erosion/weathering of the layers underneath.
As an aside, I thought the pyramids were mostly constructed of limestone with granite only on a few interior walls and features. Same arguments about emissivity apply to limestone. If granite is seen on currently exposed faces of the pyramids that is a far bigger clue to interior passages than any thermal differences.
Indeed you are right, limestone was used on the outside granite only on the chambers.
The image in question:
I wonder if water could have accumulated somehow increasing the thermal capacity.
But I wonder what they are doing here, surely inside a pyramid chamber will be as close to equilibrium as you can possibly get, even if there was air behind a stone it's not going to have enough heat mass to change the surface temperature, unless as you say its a very thin stone sheet.
Wow, sounds like they went to town to prove this. It's not like someone with a Flir just showed up and waved it around.
I can remember the UPUAT II robot in the air shaft finding that door. That was exciting. Don't recall whatever came of that.
Simply tear it down beginning at the top stone. then you'll know for sure.
All that work for a pile of rocks with a long dead guy in it...
Wouldn't this be relatively easy to detect with SONAR/ultrasound? Send acoustic pings through the walls and look for reflections caused by the discontinuity where the wall becomes air in the hidden room?
Wouldn't this be relatively easy to detect with SONAR/ultrasound? Send acoustic pings through the walls and look for reflections caused by the discontinuity where the wall becomes air in the hidden room?
I was thinking along the same lines but somehow progress doesn't arrive at all places. For example: yesterday I was reading an article about a completely new invention which allows to measure the depth of burn wounds without physical contact and that everybody was so happy with it. Several years ago I build a device (for a customer) which does the same and much better because it also produces a 3D model of the wound.
Also some colleagues of mine are working on 'cosmic ray muon tomography' I believe this is/will be used to look at the internal structure of the pyramids. As well as the internal structure of the Fukushima reactors/volcanoes/look for very dense e.g. nuclear materials in shipping containers at ports. I don't know a lot about it but I understand it works like an x-ray machine but it uses the passive background level of muons caused by cosmic rays to illuminate an object and create an image.
Damn, they found my super secret fusion power core im building to help me take over the world...
Who would have thought some idiots drags thermal camera next to pyramid...
Humans, they always find ways to suprise you...
I believe that a group headed by Alvarez did muon tomography of the great pyramid back in the 1970's, looking for unknown chambers.
Their final report specified a minimum dimension: anything larger would have been detected.
I believe that a group headed by Alvarez did muon tomography of the great pyramid back in the 1970's, looking for unknown chambers.
Their final report specified a minimum dimension: anything larger would have been detected.
I recall that was well. Nobel prize winner Luis Alvarez did it. Found nothing.
sounds like a load of spin to me, Egypt trying to keep their tourist industry going in the midst of the Sharm el Sheikh crisis