This spring’s updates to the OED see the addition of words that should be useful to anyone who dreams of traveling to other planets some day. Reach for the stars, and add these four stellar words to your vocabulary.

astrogation (ASS-troh-GAY-shun) noun
Like the well-known word navigation, this word has to do with travel, as you can see by the Latin root word agere (“to drive”) which forms the last half of both words. However, where navigation originally had to do with finding your way when sailing over the ocean (navis means “ship”), the ships of the future will drive between the stars (aster is the Greek word meaning “star”). An astrogator will plan the route her spaceship will use as she navigates around planetary gravitational fields, asteroids, and supernovae on the way to far-flung galaxies.

geosynchronous (gee-oh-SIN-kroh-nuss) adjective
Although we’re still far from interstellar travel, this word should be familiar to anyone who uses modern communication technologies, because many television, radio, and telephone systems use satellites in geosynchronous orbits to send signals. Geosynchronous literally translates to “Earth-together-time” if you look at its Greek root words (geo- = Earth; syn- = together; kronos = time), and refers to the satellite’s orbit when it matches the rotation of the Earth.

ionopause (eye-ON-oh-pawz) noun
The International Space Station (which is not in geosynchronous orbit) stays in the ionosphere, which is a layer of the Earth’s atmosphere where the ionizing radiation from the sun creates a layer of charged particles. The ionopause is the upper boundary of this layer, right below the exosphere – the very last layer before you reach outer space.

metamaterial (MEH-tah-muh-TEE-ree-uhl) noun
One of the things the astronauts do on the ISS is experiment with compounds and combinations of substances that can’t or don’t occur naturally on Earth, mostly due to the gravity-free environment of space. The goal of many scientists is to find ways to create these precisely-engineered metamaterials (using the Greek root meta-, which means “over, beyond”) and develop new ways to build stronger and better tools and equipment to keep space exploration moving forward in the 21st century.