where was the first hot air balloon invented
Hot air balloon Early unmanned hot air balloons were used in China. Zhuge Liang of the Shu Han kingdom, during the Three Kingdoms era (220–280 AD), used airborne lanterns for military signaling. These lanterns are known Chinese lanterns (simplified Chinese: 孔明灯; traditional Chinese: 孔明燈).[4]
James Dewar He next experimented with a high-pressure hydrogen jet by which low temperatures were realised through the Joule–Thomson effect, and the successful results he obtained led him to build at the Royal Institution a large regenerative cooling refrigerating machine. Using this machine in 1898, liquid hydrogen was collected for the first time, solid hydrogen following in 1899. He tried to liquefy the last remaining gas, helium, which condenses into a liquid at −268.9 °C, but owing to a number of factors, including a short supply of helium, Dewar was preceded by Heike Kamerlingh Onnes as the first person to produce liquid helium, in 1908. Onnes would later be awarded the Nobel Prize in Physics for his research into the properties of matter at low temperatures – Dewar was nominated several times, but never succeeded in winning the Nobel Prize.[6]