The lowest natural temperature ever directly recorded atground level on Earth is −89.2 °C (−128.6 °F; 184.0 K) at the then-SovietVostok Station inAntarctica on 21 July 1983 by ground measurements.[1]
On 10 August 2010, satellite observations showed a surface temperature of −92 °C (−134 °F; 181 K) at81°48′S59°18′E / 81.8°S 59.3°E /-81.8; 59.3, along a ridge betweenDome Argus andDome Fuji, at 3,900 m (12,800 ft) elevation.[2] The result was reported at the 46th annual meeting of theAmerican Geophysical Union inSan Francisco, California, in December 2013; it is a provisional figure, and may be subject to revision.[3] The value is not listed as the record lowest temperature as it was measured byremote sensing from satellite and not by ground-basedthermometers, unlike the 1983 record.[4] The temperature announced reflects that of the ice surface, while the Vostok readings measured the air above the ice, and so the two are not directly comparable. Later work[5] shows many locations in the high Antarctic where surface temperatures drop to approximately −98 °C (−144 °F; 175 K). Due to the very strong temperature gradient near the surface, these imply near-surface air temperature minima of approximately −94 °C (−137 °F; 179 K).
On 21 January 1838, a Russian merchant named Neverov recorded a temperature of −60 °C (−76 °F; 213 K) inYakutsk.[6] On 15 January 1885, H. Wild reported that a temperature of −68 °C (−90 °F; 205 K) was measured inVerkhoyansk.[6] A later measurement at the same place in February 1892 was reported as −69.8 °C (−93.6 °F; 203.3 K). Soviet researchers later announced a recording of −67.7 °C (−89.9 °F; 205.5 K) in February 1933 atOymyakon, about 650 km (400 mi) to the south-east of Verkhoyansk; this measurement was reported by Soviet texts through the 1940s as a record low, with the previous measurement from Verkhoyansk retroactively adjusted to −67.6 °C (−89.7 °F; 205.6 K).[7]
The next reliable measurement was made during the 1957 season at theAmundsen–Scott South Pole Station inAntarctica, yielding −73.6 °C (−100.5 °F; 199.6 K) on 11 May and −74.5 °C (−102.1 °F; 198.7 K) on 17 September.[6] The next world record low temperature was a reading of −88.3 °C (−126.9 °F; 184.8 K), measured at the SovietVostok Station in 1968, on theAntarctic Plateau. Vostok again broke its own record with a reading of −89.2 °C (−128.6 °F; 184.0 K) on 21 July 1983.[8] This remains the record for a directly recorded temperature.
In 1904, Dutch scientistHeike Kamerlingh Onnes created a special lab inLeiden in the Netherlands with the aim of producingliquid helium. In 1908, he managed to lower the temperature to less than −269 °C (−452.20 °F; 4.15 K), which is four degrees aboveabsolute zero. Only in this exceptionally cold state will helium liquefy; the boiling point of helium being −268.94 °C (−452.09 °F; 4.21 K). Kamerlingh Onnes received aNobel Prize in Physics for his achievement.[9]
Onnes' method relied upon depressurising the subject gases, causing them to cool byadiabatic cooling.[citation needed] This follows from the first law of thermodynamics;
whereU =internal energy,Q =heat added to the system,W =work done by the system.
Consider a gas in a box of set volume. If the pressure in the box is higher than atmospheric pressure, then upon opening the gas will do work on the surrounding atmosphere to expand. As this expansion isadiabatic and the gas has done work
Now as the internal energy has decreased, so has the temperature.[citation needed]
As of November 2000,nuclear spin temperatures below 100 pK were reported for an experiment at theHelsinki University of Technology Low Temperature Lab. However, this was the temperature of one particular type of motion—a quantum property called nuclear spin—not the overall average thermodynamic temperature for all possible degrees of freedom.[10] At such low temperatures, the concept of "temperature" becomes multifaceted since molecular motion cannot be assumed to average out across degrees of freedom.[citation needed] The corresponding peak emission will be in radio waves, rather than in the familiar infrared, so it is very inefficiently absorbed by neighboring atoms, making it difficult to reach thermal equilibrium.
The Low Temperature Laboratory recorded a record low temperature of 100pK, or 1.0 × 10−10 K in 1999.[11]
The current apparatus for achieving low temperatures has two stages. The first uses ahelium dilution refrigerator to get to temperatures of millikelvins, then the next stage usesadiabatic nuclear demagnetisation to reach picokelvins.[11]
Extremely low temperatures are useful for observation ofquantum mechanical phases of matter such assuperfluids andBose–Einstein condensates, which would be disrupted by thermal motions.