# science \[hottest temperature\] **URL:** \ **Category:** Factual Questions\ **Created:** [March 11, 2010, 2:04pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100 "2010-03-11T14:04:00Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![usmc8792](https://avatars.discourse-cdn.com/v4/letter/u/d6d6ee/32.png) [@usmc8792](https://boards.straightdope.com/u/usmc8792)\ **Post date:** [March 11, 2010, 2:04pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/1 "2010-03-11T14:04:00Z")
Does black heat exist? ---
**Author:** ![Superfluous\_Parentheses](https://avatars.discourse-cdn.com/v4/letter/s/8edcca/32.png) [@Superfluous\_Parentheses](https://boards.straightdope.com/u/Superfluous_Parentheses)\ **Post date:** [March 11, 2010, 2:07pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/2 "2010-03-11T14:07:52Z")
Depends on what you mean. AFAIK it’s quite possible for an object to radiate heat but no visible light. ---
**Author:** ![Superfluous\_Parentheses](https://avatars.discourse-cdn.com/v4/letter/s/8edcca/32.png) [@Superfluous\_Parentheses](https://boards.straightdope.com/u/Superfluous_Parentheses)\ **Post date:** [March 11, 2010, 2:16pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/3 "2010-03-11T14:16:21Z")
Follow up: [this text (2nd diagram)](http://hea-www.harvard.edu/~efortin/thesis/html/Black_body.shtml) indicates that black bodies at 300K (about room temperature) radiate no visible light ---
**Author:** ![Richard\_Pearse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/richard_pearse/32/13144_2.png) [@Richard\_Pearse](https://boards.straightdope.com/u/Richard_Pearse)\ **Post date:** [March 11, 2010, 2:21pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/4 "2010-03-11T14:21:25Z")
Don’t almost all objects radiate heat without visible light? If you close up a room and turn all the lights off, there’s no light but there’s plenty of IR being radiated. ---
**Author:** ![Grey](https://avatars.discourse-cdn.com/v4/letter/g/b782af/32.png) [@Grey](https://boards.straightdope.com/u/Grey)\ **Post date:** [March 11, 2010, 2:25pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/5 "2010-03-11T14:25:44Z")
First off what the hell is “black heat”? Heat, is simply a transfer of energy across system boundaries. If, what you’re asking is "Can heat be invisible to the naked eye?’ then yeah - I mean ever seen a ice cube melt in a blinding flash of light while cooling your drink? ---
**Author:** ![Tapioca\_Dextrin](https://avatars.discourse-cdn.com/v4/letter/t/3d9bf3/32.png) [@Tapioca\_Dextrin](https://boards.straightdope.com/u/Tapioca_Dextrin)\ **Post date:** [March 11, 2010, 2:46pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/6 "2010-03-11T14:46:56Z")
> [@usmc8792](#): > > Does black heat exist? [Yes](http://www.imdb.com/title/tt0125015/). You can buy it on Amazon. ---
**Author:** ![usmc8792](https://avatars.discourse-cdn.com/v4/letter/u/d6d6ee/32.png) [@usmc8792](https://boards.straightdope.com/u/usmc8792)\ **Post date:** [March 11, 2010, 3:03pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/7 "2010-03-11T15:03:52Z")
I mean what is the hottest heat there is ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [March 11, 2010, 3:05pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/8 "2010-03-11T15:05:45Z")
You mean beyond red, white, blue heat, etc? ---
**Author:** ![YamatoTwinkie](https://avatars.discourse-cdn.com/v4/letter/y/cc9497/32.png) [@YamatoTwinkie](https://boards.straightdope.com/u/YamatoTwinkie)\ **Post date:** [March 11, 2010, 3:11pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/9 "2010-03-11T15:11:03Z")
> [@usmc8792](#): > > I mean what is the hottest heat there is The master [speaks](http://www.straightdope.com/columns/read/807/what-is-the-opposite-of-absolute-zero). ---
**Author:** ![usmc8792](https://avatars.discourse-cdn.com/v4/letter/u/d6d6ee/32.png) [@usmc8792](https://boards.straightdope.com/u/usmc8792)\ **Post date:** [March 11, 2010, 3:16pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/10 "2010-03-11T15:16:54Z")
yes beyond red,blue,etc ---
**Author:** ![Grey](https://avatars.discourse-cdn.com/v4/letter/g/b782af/32.png) [@Grey](https://boards.straightdope.com/u/Grey)\ **Post date:** [March 11, 2010, 3:30pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/11 "2010-03-11T15:30:04Z")
That’s not heat - that’s temperature. You _feel_ the transfer of energy from an object to your body (say from red iron to your hand), but it’s the temperature of the object that’s linked to colour. Stupid too when you consider that red hot iron is not at the same temperature as red hot titanium. Basically the more energy your pour into a single contained system the hotter it gets, with limits set by the available energy of the universe, the ability of the system to contain itself and general quantum weirdness. ---
**Author:** ![lazybratsche](https://avatars.discourse-cdn.com/v4/letter/l/ba8739/32.png) [@lazybratsche](https://boards.straightdope.com/u/lazybratsche)\ **Post date:** [March 11, 2010, 3:42pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/12 "2010-03-11T15:42:09Z")
> [@Grey](#): > > Stupid too when you consider that red hot iron is not at the same temperature as red hot titanium. Wait, really? I thought that absent any major absorption or emission, all black body radiation will give the same color at a given temperature. ---
**Author:** ![usmc8792](https://avatars.discourse-cdn.com/v4/letter/u/d6d6ee/32.png) [@usmc8792](https://boards.straightdope.com/u/usmc8792)\ **Post date:** [March 11, 2010, 3:52pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/13 "2010-03-11T15:52:57Z")
but can it get too hot to see ---
**Author:** ![lazybratsche](https://avatars.discourse-cdn.com/v4/letter/l/ba8739/32.png) [@lazybratsche](https://boards.straightdope.com/u/lazybratsche)\ **Post date:** [March 11, 2010, 4:01pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/14 "2010-03-11T16:01:47Z")
> [@usmc8792](#): > > but can it get too hot to see I don’t think so. As the temperature gets extremely high, the peak emission will be at a higher frequency than visible light, but there will still be plenty of visible emissions as well. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [March 11, 2010, 4:07pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/15 "2010-03-11T16:07:21Z")
I think it’s possible for an object to get so hot that it emits only X rays, but if you’re looking at it as it warms up to this temperature, things might go black for an entirely different reason. ---
**Author:** ![Grey](https://avatars.discourse-cdn.com/v4/letter/g/b782af/32.png) [@Grey](https://boards.straightdope.com/u/Grey)\ **Post date:** [March 11, 2010, 4:13pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/16 "2010-03-11T16:13:28Z")
> [@lazybratsche](#): > > Wait, really? I thought that absent any major absorption or emission, all black body radiation will give the same color at a given temperature. Nope I was wrong - [Wein’s displacement law](http://en.wikipedia.org/wiki/Wien%27s_displacement_law) ---
**Author:** ![WarmNPrickly](https://avatars.discourse-cdn.com/v4/letter/w/d78d45/32.png) [@WarmNPrickly](https://boards.straightdope.com/u/WarmNPrickly)\ **Post date:** [March 11, 2010, 5:38pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/17 "2010-03-11T17:38:17Z")
> [@Grey](#): > > Nope I was wrong - [Wein’s displacement law](http://en.wikipedia.org/wiki/Wien%27s_displacement_law) Well if you want to wiggle yourself out of trouble, technically the iron and titanium are not black bodies, so they will have a different color. I don’t know how different, but I’m certain that there are some absorption bands that will slightly deviate from Wein’s displacement law. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [March 11, 2010, 5:52pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/18 "2010-03-11T17:52:54Z")
Edited title to indicate subject. Colibri General Questions Moderator ---
**Author:** ![Grey](https://avatars.discourse-cdn.com/v4/letter/g/b782af/32.png) [@Grey](https://boards.straightdope.com/u/Grey)\ **Post date:** [March 11, 2010, 6:14pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/19 "2010-03-11T18:14:51Z")
> [@WarmNPrickly](#): > > Well if you want to wiggle yourself out of trouble, technically the iron and titanium are not black bodies, so they will have a different color. I don’t know how different, but I’m certain that there are some absorption bands that will slightly deviate from Wein’s displacement law. Nah, I’ll take the hit. 🙂 Was a stupid thing to fling out there without considering what I was saying. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [March 11, 2010, 11:30pm UTC](https://boards.straightdope.com/t/science-hottest-temperature/532100/20 "2010-03-11T23:30:15Z")
> [@](#): > > I think it’s possible for an object to get so hot that it emits only X rays, but if you’re looking at it as it warms up to this temperature, things might go black for an entirely different reason. No. When you heat up an object, the amount of visible light increases (as does the amount of IR, the amount of UV, or any other wavelength band). You can certainly get to a temperature where the amount of X-rays increases _more_ than the visible light does, so in relative terms, the total emission becomes more X-ray dominated, but in absolute terms, there’s still more visible light there than there was before. [Next page](https://boards.straightdope.com/t/science-hottest-temperature/532100.md?page=2)