[Jay Seneca]

I used a Milwaukee infrared thermometer and pointed it towards the sun. I had to hit it exactly or a little to the left,  right, up or down and the temperature went to 0-50 degrees. But when I did aim it directly on the sun the temperature immediately rose to >500 degrees Fahrenheit.  Does that tell me the earth is closer than 85 million miles or 8 light minutes away?

[TierraPlana]

No because at ground level the contribution of infra-red radiation from the Sun has a negligible effect on any temperature variation. Whatever caused your temperature variation to that extent it wasn't the Sun.

[Jay Seneca]

No. It’s definitely the sun making it do that. It has to be exactly on the Sun.  Tested everyday for 2 weeks. After 3pm the temperature would only show 420F and it’s more difficult to hit.

[Pete Svarrior]

You're misusing your IR thermometer. By pointing it at the sky, you're capturing largely unfocused infrared radiation, and any readings you may have obtained will be largely unrelated to real world temperatures.

Yeah, you probably captured more IR when you pointed it at the Sun. But it'll mean absolutely nothing.

[Jay Seneca]

It’s not the exact temperature I’m curious about. Because over a distance it does lose accuracy.  It’s the immediate rise in temperature when I point it directly at the sun, in 1-2 seconds the temperature readings start to rise. It takes light 8 minutes to get to the sun. So is a infrared thermometer faster than light?
And the sun was the only thing in the sky.

[rpt]

It takes light 8 minutes to get to the sun. So is a infrared thermometer faster than light?

Why does it matter how far away the sun is? Light isn't going to the sun, radiation is coming from the sun.

I think you misunderstand how an infrared thermometer works. All it does is record the radiation falling on it, so it isn't surprising that when you point it at the sun it reads a higher temperature.

[somerled]

No. It’s definitely the sun making it do that. It has to be exactly on the Sun.  Tested everyday for 2 weeks. After 3pm the temperature would only show 420F and it’s more difficult to hit.

Those are interesting observations . Measuring that temp. change throughout the day , and the suns angle , would be worth doing hmmm.

[Jay Seneca]

When I say directly on the sun, I mean I have about 1 square inch I have to hit and anything more to the left or right and the temperature drops to 0-30F.
Maybe I’m misunderstanding how infrared works.  But the only radiation in the sky is when I point it directly at the sun?

[Pete Svarrior]

It takes light 8 minutes to get to the sun. So is a infrared thermometer faster than light?

Your thermometer measures radiation that hits it. Sure, light coming from the Sun will take some time (whatever that may be) to reach us. But that also means that there is light that's already left the Sun and which is on the way to us, since it's a (more or less) constant stream.

[Tom Bishop]

The value the device reads probably does reflect the temperature of something. Why else would it report that and change at different times of the day?

However, it seems that it is likely measuring the temperature of the atmolayer localized to the observer's position rather than the temperature of the sun itself. What is the maximum range of the thermometer?

[Pete Svarrior]

The value the device reads probably does reflect the temperature of something. Why else would it report that and change at different times of the day?

Not really. In order to actually measure the temperature of something, it would have to be able to focus on the IR source.

What it does is capture some unfocused ambient IR and perform the same calculations as it would if used correctly. Electronic devices have limitations - if you choose to misuse them, the insight gathered will be limited.

Of course, the link you propose is still there - if everything around you gets colder, there will be less ambient IR for you to capture.

[Jay Seneca]

But if it was reading the radiation for a distant sun it would be distributed almost the same through the entire sky.  It would not be limited to a square inch and move the gun 1/2” one way or the other and the temperature drops from 450F to 50F.

[rpt]

Can you look directly at the sun without it burning your eyes (or at least feeling like that)? Whether you observe the sun with your eyes or an IR thermometer it is exactly the same.

[Jay Seneca]

Does anyone think this would work.

Testing to see if the sun is in our atmosphere and should the size of the sun.

The last week of July between 12:00-1300 was the first time I pointed the infrared gun at the sun.  It gave me a reading over 800F. It shocked me caught me off guard but I do remember running inside the control room and showing a co-worker. The sun was basically directly over my location.
This infrared thermometer has a 10:1 ratio. So if the sun is directly over my location and has an elevation of 200 miles the infrared gun will be taking that temperature over a diameter of 20mile.  If I keep testing and documenting the temperatures of the sun as it travels west.  And when the temperature reading eventually drops a lot more and out of pattern with the previous readings then I’ll know that the (10:1)infrared testing area is larger than the suns surface. Then I’ll keep testing and comparing temperature drop due to infrared thermometer testing area becoming increasingly larger than the sun. With the help of time zones getting the western distance from the sun should be quite easy.  Honestly I’ll probably struggle then eventually fail Due to Math.

[somerled]

Keep doing the readings please . If the sun is 93,000,000 away and you get that reading pointing towards the sun at midday then that reading should be similar pointing the thermometer at the sun all over the sky till the sun is low at the horizon . Infra red wavelengths are affected less than visible wavelengths by atmospheric refraction and dispersion .
    In fact we can look directly at the sun at dawn and dusk , but don't do that on my account . It would be nice to see whether the thermometer picks up any difference between the visible sun position and the infrared hotspot position at those times .

[Jay Seneca]

Currently the Sun at 12:00-13:00 is at a minimum of 2000 miles south of my location. My IR thermometer has  a 10:1 ratio so that makes the point of contact at a minimum of 200 miles in diameter.  So it seems I will have to wait till May or June of next year before I can get another good temperature of the Sun.
Sun < 200 Miles
As of now I’m getting around 400F during 12:00. 250F around 8:00. And If I aim straight up on a clear day/night it reads -30F. 

[somerled]

Thanks for posting those observations . As I see it , pointing the thermometer at the changing sun position should not result in such a large change if the sun is huge and 93,000,000 miles away .

Was the 8:00 reading am or pm . Sun moves 4 degrees per hour  . I think that those readings could give a way , via the inverse square law and degree of change in suns position , of working out an estimate of distance to the sun .

[Jay Seneca]

AM. This time of the year it’s already dark by 8pm. And Wednesday at 2pm I was able to get a temp of 480F.  After that the temperature started to decrease.   Like I said in July around 1-2pm I was getting readings over 800F.