In 1613, Galileo Galilei attempted to measure the weight and density of air. He determined the weight of a glass flask containing compressed air. He found a value of 2.2 g/ for the density of air. This was a big step forward because air could now be considered as a substance with weight.The word vacuum comes from the Latin word Vacua which means empty. A vacuum is partially empty space where different types of gases have been removed. Vacuum means any volume containing less gas particles. A vacuum is also a gaseous environment with pressures below the atmospheric pressure.
The first sustained vacuum was achieved in 1643. The first vacuum pump followed in 1650. As flying began developing in the early 1900s, aeronautical researchers began setting up engines in vacuum test chambers to simulate higher altitudes. As the nation began sending spacecraft into space, the need for test chambers capable of producing a higher level of vacuum was apparent. The Space Power Chamber (SPC) was among the first of a wave of large vacuum chambers that emerged in the early 1960s. The Space Power Facility at NASA’s Plum Brook Station, which began operation in 1969, is the largest vacuum chamber in the world.
Air pressure is the force per unit area exerted on a surface by the weight of air above that surface in the atmosphere of earth. A vacuum chamber is a rigid enclosure from which air and other gases are removed by a vacuum pump. This results in a low pressure environment known as a vacuum. When putting balloons in a vacuum chamber the air gets taken out but the balloons still expand. When also putting in some liquid (water) it will boil in the process without getting hot and cause some precipitation.