Absolute zero is a temperature equal to zero on the thermodynamic temperature scale, i.e., it is the temperature at which all elements of a thermodynamic system obtain the lowest possible energy. This temperature corresponds to −459.67 °F = 0 K. 1)
Escape velocity is the speed that must be given to a body to enter Earth orbit. 2)
The Moon is a sphere. But its disk looks flat - it lacks the shading characteristic of a sphere illuminated by directional light. The Moon's ground reflects more light back toward its source than in other directions. This property is rare on Earth, but quite common among rocky celestial bodies. 3)
A law formulated by Euler in 1755 states that a flat body immersed in a liquid is subjected to a pressure whose value is independent of the orientation of that body in space. 4)
Synthesis gas (water-gas) is a flammable gas formed when coal, natural gas, or light hydrocarbons react with water vapor in the presence of suitable catalysts. It is a mixture of carbon monoxide (CO) and hydrogen (H2) and may contain significant amounts of nitrogen. Synthesis gas is used as a feedstock for many chemical syntheses (for example, to obtain methanol and ethanol). In addition, synthesis gas is used to obtain syntine (synthetic gasoline). 5)