Artemis II is carrying astronauts to the moon

app: Short for application, or a computer program designed for a specific task.

astronaut: Someone trained to travel into space for research and exploration.

engine: A machine designed to convert energy into useful mechanical motion. Sometimes an engine is called a motor. 

field: (in physics) A region in space where certain physical effects operate, such as magnetism (created by a magnetic field), gravity (by a gravitational field), mass (by a Higgs field) or electricity (by an electrical field).

frequency: The number of times some periodic phenomenon occurs within a specified time interval.

International Space Station: An artificial satellite that orbits Earth. Run by the United States and Russia, this station provides a research laboratory from which scientists can conduct experiments in biology, physics and astronomy — and make observations of Earth.

low-Earth orbit: An orbit fairly close to Earth’s surface — usually no more than 1,000 kilometers (620 miles), and perhaps no more than 160 km (99 mi) up. Commercial airlines, in contrast, tend to fly no higher than 14 km, or less than a tenth of the minimum low-Earth orbit.

lunar: Of or relating to Earth’s moon.

magnetic field: An area of influence created by certain materials, called magnets, or by the movement of electric charges.

moon: The natural satellite of any planet.

NASA: Short for the National Aeronautics and Space Administration. Created in 1958, this U.S. agency has become a leader in space research and in stimulating public interest in space exploration. It was through NASA that the United States sent people into orbit and ultimately to the moon. It also has sent research craft to study planets and other celestial objects in our solar system.

orbit: The curved path of a celestial object or spacecraft around a galaxy, star, planet or moon. One complete circuit around a celestial body.

particle: A minute amount of something.

radiation: (in physics) One of the three major ways that energy is transferred. (The other two are conduction and convection.) In radiation, electromagnetic waves carry energy from one place to another. Unlike conduction and convection, which need material to help transfer the energy, radiation can transfer energy across empty space.

rocket: Something propelled into the air or through space, sometimes as a weapon of war. A rocket usually is lofted by the release of exhaust gases as some fuel burns. (v.) Something that flings into space at high speed as if fueled by combustion.

sensor: A device that picks up information on physical or chemical conditions — such as temperature, barometric pressure, salinity, humidity, pH, light intensity or radiation — and stores or broadcasts that information. Scientists and engineers often rely on sensors to inform them of conditions that may change over time or that exist far from where a researcher can measure them directly.

stress:  (in psychology) A mental, physical, emotional or behavioral reaction to an event or circumstance (stressor) that disturbs a person or animal’s usual state of being or places increased demands on a person or animal; psychological stress can be either positive or negative.

supersonic: Moving at somewhere between one and five times the speed of sound in air.

system: A network of parts that together work to achieve some function. For instance, the blood, vessels and heart are primary components of the human body’s circulatory system. Similarly, trains, platforms, tracks, roadway signals and overpasses are among the potential components of a nation’s railway system. System can even be applied to the processes or ideas that are part of some method or ordered set of procedures for getting a task done.

technology: The application of scientific knowledge for practical purposes, or the devices, processes and systems that result from those efforts.