astronaut: Someone trained to travel into space for research and exploration.
average: (in science) A term for the arithmetic mean, which is the sum of a group of numbers that is then divided by the size of the group.
brain scan: A technique to view structures inside the brain, typically with X-rays or a magnetic resonance imaging (or MRI) machine. With MRI technology — especially the type known as functional MRI (or fMRI) — the activity of different brain regions can be viewed during an event, such as viewing pictures, computing sums or listening to music.
colleague: Someone who works with another; a co-worker or team member.
gravity: The force that attracts anything with mass, or bulk, toward any other thing with mass. The more mass that something has, the greater its gravity.
liquid: A material that flows freely but keeps a constant volume, like water or oil.
Mars: The fourth planet from the sun, just one planet out from Earth. Like Earth, it has seasons and moisture. But its diameter is only about half as big as Earth’s.
MRI: Short for magnetic resonance imaging. It’s an imaging technique to visualize soft, internal organs, like the brain, muscles, heart and cancerous tumors. MRI uses strong magnetic fields to record the activity of individual atoms.
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.
organ: (in biology) Various parts of an organism that perform one or more particular functions. For instance, an ovary is an organ that makes eggs, the brain is an organ that makes sense of nerve signals and a plant’s roots are organs that take in nutrients and moisture.
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.
technology: The application of scientific knowledge for practical purposes, especially in industry — or the devices, processes and systems that result from those efforts.
waste: Any materials that are left over from biological or other systems that have no value, so they can be disposed of as trash or recycled for some new use.