astronomer: A scientist who works in the field of research that deals with celestial objects, space and the physical universe.
celestial: (in astronomy) Of or relating to the sky, or outer space.
computer program: A set of instructions that a computer uses to perform some analysis or computation. The writing of these instructions is known as computer programming.
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.
density: The measure of how condensed some object is, found by dividing its mass by its volume.
diameter: The length of a straight line that runs through the center of a circle or spherical object, starting at the edge on one side and ending at the edge on the far side.
diversity: A broad spectrum of similar items, ideas or people. In a social context, it may refer to a diversity of experiences and cultural backgrounds. (in biology) A range of different life forms.
exoplanet: Short for extrasolar planet, it’s a planet that orbits a star outside our solar system.
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.
helium: An inert gas that is the lightest member of the noble gas series. Helium can become a solid at -272 degrees Celsius (-458 degrees Fahrenheit).
host: (in biology and medicine) The organism (or environment) in which some other thing resides. Humans may be a temporary host for food-poisoning germs or other infective agents. (v.) The act of providing a home or environment for something.
hydrogen: The lightest element in the universe. As a gas, it is colorless, odorless and highly flammable. It’s an integral part of many fuels, fats and chemicals that make up living tissues. It’s made of a single proton (which serves as its nucleus) orbited by a single electron.
Jupiter: (in astronomy) The solar system’s largest planet, it has the shortest day length (9 hours, 55 minutes). A gas giant, its low density indicates that this planet is composed mostly of the light elements hydrogen and helium. This planet also releases more heat than it receives from the sun as gravity compresses its mass (and slowly shrinks the planet).
link: A connection between two people or things.
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.
Milky Way: The galaxy in which Earth’s solar system resides.
orbit: The curved path of a celestial object or spacecraft around a galaxy, star, planet or moon. One complete circuit around a celestial body.
planet: A large celestial object that orbits a star but unlike a star does not generate any visible light.
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.
solar: Having to do with the sun or the radiation it emits. It comes from sol, Latin for sun.
solar system: The eight major planets and their moons in orbit around our sun, together with smaller bodies in the form of dwarf planets, asteroids, meteoroids and comets.
star: The basic building block from which galaxies are made. Stars develop when gravity compacts clouds of gas. When they become hot enough, stars will emit light and sometimes other forms of electromagnetic radiation. The sun is our closest star.
technology: The application of scientific knowledge for practical purposes, especially in industry — or the devices, processes and systems that result from those efforts.
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.
terrestrial: Having to do with planet Earth, especially its land. Terra is Latin for Earth.
transit: (in astronomy) The passing of a planet, asteroid or comet across the face of a star, or of a moon across the face of a planet.
velocity: The speed of something in a given direction.
