Space Agency proposed research in space to achieve femtokelvin temperatures. In May 2006, the Institute of Quantum Optics at the University of Hannover gave details of technologies and benefits of femtokelvin research in space. In January 2013, physicist Ulrich Schneider of the University of Munich in Germany reported to have achieved temperatures formally below absolute zero ("negative temperature") in gases. The gas is artificially forced out of equilibrium into a high potential energy state, which is, however, cold. When it then emits radiation it approaches the equilibrium, and can continue emitting despite reaching formal absolute zero; thus, the temperature is formally negative. In September 2014, scientists in the CUORE collaboration at the Laboratori Nazionali del Gran Sasso in Italy cooled a copper vessel with a volume of one cubic meter to for 15 days, setting a record for the lowest temperature in the known universe over such a large contiguous volume. In June 2015, experimental physicists at MIT cooled molecules in a gas of sodium potassium to a temperature of 500 nanokelvin, and it is expected to exhibit an exotic state of matter by cooling these molecules somewhat further. In 2017, Cold Atom Laboratory (CAL), an experimental instrument was developed for launch to the International Space Station (ISS) in 2018. The instrument has created extremely cold conditions in the microgravity environment of the ISS leading to the formation of Bose–Einstein condensates. In this space-based laboratory, temperatures as low as 1 picokelvin (10−12 K) temperatures are projected to be achievable, and it could further the exploration of unknown quantum mechanical phenomena and test some of the most fundamental laws of physics. The current world record for effective temperatures was set in 2021 at 38 picokelvin (pK), or 0.000000000038 of a kelvin, through matter-wave lensing of rubidium Bose–Einstein condensates. See also Kelvin (unit of temperature) Charles's law Heat International Temperature Scale of 1990 Orders of magnitude (temperature) Thermodynamic temperature Triple point Ultracold atom Kinetic energy Entropy Planck temperature and Hagedorn temperature, hypothetical upper limits to the thermodynamic temperature scale References Further reading BIPM Mise en pratique - Kelvin - Appendix 2 - SI Brochure External links "Absolute zero": a two part NOVA episode originally aired January 2008 "What is absolute zero?" Lansing State Journal Cold Cryogenics Temperature