axis of rotation: The imaginary line about which something rotates. On a wheel, the axis would go straight through the center and stick out on either side.
Cassini: A space probe sent by NASA to explore the planet Saturn. Cassini was launched from Earth in 1997. It reached Saturn in late 2004. The craft included a variety of instruments meant to study Saturn’s moons, rings, magnetic field and atmosphere.
colleague: Someone who works with another; a co-worker or team member.
data: Facts and/or statistics collected together for analysis but not necessarily organized in a way that gives them meaning. For digital information (the type stored by computers), those data typically are numbers stored in a binary code, portrayed as strings of zeros and ones.
debris: Scattered fragments, typically of trash or of something that has been destroyed. Space debris, for instance, includes the wreckage of defunct satellites and spacecraft.
dinosaur: A term that means terrible lizard. These reptiles emerged around 243 million years ago. All descended from egg-laying reptiles known as archosaurs. Their descendants eventually split into two lines. For many decades, they have been distinguished by their hips. The lizard-hipped line are believed to have led to the saurischians, such as two-footed theropods like T. rex and the lumbering four-footed Apatosaurus. A second line of so-called bird-hipped, or ornithischian dinosaurs, appears to have led to a widely differing group of animals that included the stegosaurs and duckbilled dinosaurs. Many large dinosaurs died out around 66 million years ago. But some saurischians lived on. They are now the birds we see today (and who have now evolved that so-called “bird-hipped” pelvis).
dormant: Inactive to the point where normal body functions are suspended or slowed down.
force: Some outside influence that can change the motion of a body, hold bodies close to one another, or produce motion or stress in a stationary body.
gas giant: A giant planet that is made mostly of helium and hydrogen, which on Earth are gases. Jupiter and Saturn are gas giants.
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.
hypothesis: (v. hypothesize) A proposed explanation for a phenomenon. In science, a hypothesis is an idea that must be rigorously tested before it is accepted or rejected.
hypothetical: An adjective that described some hypothesis, or proposed explanation for a phenomenon.
lunar: Of or relating to Earth’s moon.
mass: A number that shows how much an object resists speeding up and slowing down — basically a measure of how much matter that object is made from.
moment of inertia: A numerical value that describes the tendency of something to resist angular acceleration (a change in the speed at which it spins). This value is computed as the sum of the products of the mass of each particle in the body with the square of its distance from the axis of rotation.
moon: The natural satellite of any planet.
Neptune: The farthest giant planet from the sun in our solar system. It is the fourth largest planet in the 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.
phenomenon: Something that is surprising or unusual.
resonance: (adj. resonant) To have a feeling, thought, or memory that has been triggered by seeing, hearing, learning or reading something else. (in physics) The quality of being loud and clear, or, making sound by vibrating another thing. Or a term for some system in which an external stimulus has set up a large vibration of some kind, the frequency of which matches that of the stimulus.
satellite: A moon orbiting a planet or a vehicle or other manufactured object that orbits some celestial body in space.
Saturn: The sixth planet out from the sun in our solar system. One of the two gas giants, this planet takes 10.6 hours to rotate (completing a day) and 29.5 Earth years to complete one orbit of the sun. It has at least 82 moons. But what most distinguishes this planet is the broad and flat plane of bright rings that orbit it.
scenario: A possible (or likely) sequence of events and how they might play out.
simulation: (v. simulate) An analysis, often made using a computer, of some conditions, functions or appearance of a physical system. A computer program would do this by using mathematical operations that can describe the system and how it might change over time or in response to different anticipated situations.
sun: The star at the center of Earth’s solar system. It is about 27,000 light-years from the center of the Milky Way galaxy. Also a term for any sunlike star.
telescope: Usually a light-collecting instrument that makes distant objects appear nearer through the use of lenses or a combination of curved mirrors and lenses. Some, however, collect radio emissions (energy from a different portion of the electromagnetic spectrum) through a network of antennas.
titan: The term for any gigantic being. The term comes from Greek mythology. The six sons and six daughters of the Greek gods Uranus and Gaea were known as titans. Capitalized Titan is a moon of Saturn.
