# temperature R **URL:** \ **Category:** Factual Questions\ **Created:** [September 15, 2002, 2:39am UTC](https://boards.straightdope.com/t/temperature-r/128493 "2002-09-15T02:39:10Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![SlickRoenick](https://avatars.discourse-cdn.com/v4/letter/s/e68b1a/32.png) [@SlickRoenick](https://boards.straightdope.com/u/SlickRoenick)\ **Post date:** [September 15, 2002, 2:39am UTC](https://boards.straightdope.com/t/temperature-r/128493/1 "2002-09-15T02:39:10Z")
On my graphing calculator (TI-86) I have temperature conversions. I know the F, C, and K–BUT, there is one called R. What is it and how does it measure up with the other temps? ---
**Author:** ![bibliophage](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bibliophage/32/7615_2.png) [@bibliophage](https://boards.straightdope.com/u/bibliophage)\ **Post date:** [September 15, 2002, 2:50am UTC](https://boards.straightdope.com/t/temperature-r/128493/2 "2002-09-15T02:50:23Z")
The Rankine scale is an absolute temperature scale (meaning absolute zero is 0ºR). The magnitude of a degree is the same as on the Fahrenheit scale, so the temperature on the Rankine scale is always a little less than 460º lower than the corresponding temperature on the Fahrenheit scale. The scale is named after William John Macquorn Rankine. ---
**Author:** ![andy\_fl](https://avatars.discourse-cdn.com/v4/letter/a/49beb7/32.png) [@andy\_fl](https://boards.straightdope.com/u/andy_fl)\ **Post date:** [September 15, 2002, 2:51am UTC](https://boards.straightdope.com/t/temperature-r/128493/3 "2002-09-15T02:51:59Z")
°R is for Rankin, the Russian Temperature unit. Rankine is based on the same size units as °Fahrenheit except that water freezes at 459.67 Rankine ---
**Author:** ![robby](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/robby/32/11048_2.png) [@robby](https://boards.straightdope.com/u/robby)\ **Post date:** [September 15, 2002, 2:52am UTC](https://boards.straightdope.com/t/temperature-r/128493/4 "2002-09-15T02:52:30Z")
That temperature scale is degrees Rankine, the non-metric absolute temperature scale. (“Absolute”, meaning that zero deg R is absolute zero.) Zero degrees Rankine is thus the same temperature as zero kelvins, that is, absolute zero. Zero deg R is also equal to -459.67 deg F. A Rankine degree is the same size as a Farenheit degree. A kelvin is the same size as a Celsius degree. ---
**Author:** ![bibliophage](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bibliophage/32/7615_2.png) [@bibliophage](https://boards.straightdope.com/u/bibliophage)\ **Post date:** [September 15, 2002, 2:56am UTC](https://boards.straightdope.com/t/temperature-r/128493/5 "2002-09-15T02:56:30Z")
I should note there is also a Réaumur scale, named after René Antoine Ferchault de Réaumur, but that is very rarely used. I don’t think it it was ever abbreviated **ºR** , but a dim memory suggests **ºRe** might have been used. This scale sets zero as the melting point of water (same as Celsius), but 80 as the boiling point of water. ---
**Author:** ![robby](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/robby/32/11048_2.png) [@robby](https://boards.straightdope.com/u/robby)\ **Post date:** [September 15, 2002, 3:04am UTC](https://boards.straightdope.com/t/temperature-r/128493/6 "2002-09-15T03:04:49Z")
> [@](#): > > \*Originally posted by andy\_fl \* > \*\*°R is for Rankin, the Russian Temperature unit. > > Rankine is based on the same size units as °Fahrenheit except that water freezes at 459.67 Rankine \*\* William John Macquorn Rankine was a Scottish engineer and physicist, who proposed his namesake temperature scale in 1859. I don’t know of any particular Russian connection. Also water freezes at 32 °F, not 0 °F, so in degrees Rankine, water freezes at 491.67 °R. ---
**Author:** ![Una\_Persson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/una_persson/32/346_2.png) [@Una\_Persson](https://boards.straightdope.com/u/Una_Persson)\ **Post date:** [September 15, 2002, 11:51am UTC](https://boards.straightdope.com/t/temperature-r/128493/7 "2002-09-15T11:51:49Z")
> [@](#): > > \*Originally posted by bibliophage \* > \*\*I should note there is also a Réaumur scale, named after René Antoine Ferchault de Réaumur, but that is very rarely used. I don’t think it it was ever abbreviated **ºR** , but a dim memory suggests **ºRe** might have been used. This scale sets zero as the melting point of water (same as Celsius), but 80 as the boiling point of water. \*\* The only sources I can find for the Réaumur scale say it too was denoted “ **ºR** ”. Note that there were also temperature scales created by Dalton and Giaque too, both of which are just as obsolete as Réaumur. ---
**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:** [September 15, 2002, 6:48pm UTC](https://boards.straightdope.com/t/temperature-r/128493/8 "2002-09-15T18:48:41Z")
I’ve also heard reference to an Einstein temperature scale, which is logrithmic (thus ensuring that any positive or negative number would yield a valid temperature). I’ve never, however, seen this scale actually used. ---
**Author:** ![zweisamkeit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zweisamkeit/32/4360_2.png) [@zweisamkeit](https://boards.straightdope.com/u/zweisamkeit)\ **Post date:** [September 15, 2002, 10:13pm UTC](https://boards.straightdope.com/t/temperature-r/128493/9 "2002-09-15T22:13:37Z")
> [@](#): > > _Originally posted by robby_ > I don’t know of any particular Russian connection. Well, I was all set to get out my copy of **Crime and Punishment** to mention a connection, but, uh, it wasn’t the Rankin scale. :smack: In Part 3, there’s a part that says, “… thirty degrees Réaumur…”, which, according to the notes, is equivalent to 100ºF or 38ºC. So Dostoevsky (assumedly) used the Réaumur scale.