Antarctica: A continent mostly covered in ice, which sits in the southernmost part of the world.
artificial intelligence: A type of knowledge-based decision-making exhibited by machines or computers. The term also refers to the field of study in which scientists try to create machines or computer software capable of intelligent behavior.
astronomer: A scientist who works in the field of research that deals with celestial objects, space and the physical universe.
black hole: A region of space having a gravitational field so intense that no matter or radiation (including light) can escape.
blazar: A bright and distant active galaxy that shoots powerful jets of radiation from its center and directly toward Earth.
colleague: Someone who works with another; a co-worker or team member.
core: Something — usually round-shaped — in the center of an object. (in geology) Earth’s innermost layer. Or, a long, tube-like sample drilled down into ice, soil or rock. Cores allow scientists to examine layers of sediment, dissolved chemicals, rock and fossils to see how the environment at one location changed through hundreds to thousands of years or more.
cosmic rays: Very high-energy particles, mostly protons, that bombard Earth from all directions. These particles originate outside our solar system. They are equivalent to the nucleus of an atom. They travel through space at high rates of speed (often close to the speed of light).
cosmos: (adj. cosmic) A term that refers to the universe and everything within it.
electric charge: The physical property responsible for electric force; it can be negative or positive.
galaxy: A group of stars — and usually invisible, mysterious dark matter — all held together by gravity. Giant galaxies, such as the Milky Way, often have more than 100 billion stars. The dimmest galaxies may have just a few thousand. Some galaxies also have gas and dust from which they make new stars.
gamma rays: High-energy radiation often generated by processes in and around exploding stars. Gamma rays are the most energetic form of light.
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.
neural network: Also known as a neural net. A computer program designed to manage lots of data and in complex ways. These systems consist of many (perhaps millions) of simple, densely linked connections within a computer. Each connection, or node, can perform a simple operation. One node might be connected to several feeder nodes, which send it data. Several more nodes in another layer sit ready to accept the newly processed data and act upon them in some other way. The general idea of networks was initially patterned loosely on the way nerve cells work in the brain to process signals that lead to thought and learning.
neutrino: A subatomic particle with a mass close to zero. Neutrinos rarely react with normal matter. Three kinds of neutrinos are known.
particle: A minute amount of something.
physicist: A scientist who studies the nature and properties of matter and energy.
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. (in biology) The structure that an organism uses to sense attributes of its environment, such as heat, winds, chemicals, moisture, trauma or an attack by predators.
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.
subatomic: Anything smaller than an atom, which is the smallest bit of matter that has all the properties of whatever chemical element it is (like hydrogen, iron or calcium).
supernova: (plural: supernovae or supernovas) A star that suddenly increases greatly in brightness because of a catastrophic explosion that ejects most (or sometimes all) of its mass.
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.
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.
universe: The entire cosmos: All things that exist throughout space and time. It has been expanding since its formation during an event known as the Big Bang, some 13.8 billion years ago (give or take a few hundred million years).
X-ray: A type of radiation analogous to gamma rays, but having somewhat lower energy.