GLOSSARY

accuracy (AK-yuh-ruh-see): being careful and exact

angstrom (ANG-strum): 1/10,000,000 millimeter (1/254,000,000 inch)

centrifuge (SEN-trif-yooj): a spinning machine that separates substances of different densities

chromatograph (KROH-muh-to-grahf): a device that separates substances by pushing them through a material that absorbs each substance at a different rate.

convex (KON-veks): curved outward, like the outside of a sphere

density (DEN-si-tee): how light or heavy something is for its size

electron microscope (i-LEK-tron MYE-kruh-skope): a type of microscope that uses electron beams instead of light waves

infrasonic sound (IN-fruh-son-ik SOUND): below the pitch that humans can hear

nanotechnology (NA-no-tek-NOL-uh-jee): the careful handling of the smallest amount of a substance, such as molecules and atoms, to build larger structures

optical (OP-tuh-kuhl): to do with eyesight

objective (uhb-JEK-tiv): another name for the lens in a telescope or microscope

observatories (ohb-ZUR-vuh-tor-ees): buildings that contain telescopes and other equipment used to study the sky

process (PROSS-ess): a step-by-step group of actions that have a result

reflecting (re-FLECT-ing): bouncing off

refracting (ri-FRAKT-ing): bending or changing direction

simulation (sim-yuh-LA-shuhn): a copy or imitation of something

technology (tek-NOL-uh-jee): scientific knowledge used for making practical things

ultrasound (UHL-truh-sound): sound so high-pitched that human ears can't hear it.