NASA Glenn Research Center

The NASA Glenn Research Center in Cleveland, Ohio designs and develops innovative technology to advance NASA’s missions in aeronautics and space exploration.

NASA Glenn Research Center

Science Facts Written by NASA Glenn Research Center


Newton's Three Laws of Motion

The motion of an aircraft through the air can be explained and described by physical principals discovered over 300 years ago by Sir Isaac Newton. Newton worked in many areas of mathematics and ... Continue reading

Sir Issac Newton

Kinetic Theory of Gases

Air is a gas, and gases can be studied by considering the small scale action of individual molecules or by considering the large scale action of the gas as a whole. We can directly measure, or sense, ... Continue reading


The Doppler Effect

As any object moves through the air, the air near the object is disturbed. The disturbances are transmitted through the air at a distinct speed called the speed of sound, because sound itself is just ... Continue reading

Sound is just a sensation created in the human brain in response to small pressure fluctuations in the air.


A force may be thought of as a push or pull in a specific direction. When a force is applied to an object, the object accelerates in the direction of the force according to Newton's laws of motion. ... Continue reading


Guide to Propulsion

What is propulsion? The word is derived from two Latin words: pro meaning before or forwards and pellere meaning to drive. Propulsion means to push forward or drive an object forward. A propulsion ... Continue reading

A jet engine creates thrust.

The Motion of An Aircraft

We live in a world that is defined by three spatial dimensions and one time dimension. Objects move within this domain in two ways. An object translates, or changes location, from one point to ... Continue reading


Newton's First Law of Motion

Sir Isaac Newton first presented his three laws of motion in the 'Principia Mathematica Philosophiae Naturalis' in 1686. His first law states that every object will remain at rest or in uniform motion ... Continue reading

The story of Isaac Newton discovering the laws of gravity by watching apples falling from a tree is probably just a myth. He did do his work on gravity while at a farm, but that is about as much as can be proven.

What Is Microgravity?

Gravity is a force that governs motion throughout the universe. It holds us to the ground and keeps the Earth in orbit around the Sun. Microgravity describes the environment in orbital space flight, ... Continue reading

A simple example of microgravity's effect in combustion is the behavior of flames in space. On Earth, hot air rises around a candle flame, which causes the flame to flicker and take on an elongated shape. In microgravity, however, no such distortion takes place. The flame, without the effects of gravity, has a steady, spherical, shape.

A Quick Guide To Gliders

A glider is a special kind of aircraft that has no engine. Paper airplanes are the most obvious example, but gliders come in a wide range of sizes. Toy gliders, made of balsa wood or styrofoam, are an ... Continue reading