Maybe you associate the word "zodiac" with astrology, but it has an honored place in astronomy, too. It's defined by the annual path of the sun across our sky.
Redshifts reveal how an object is moving in space, showing otherwise-invisible planets and the movements of galaxies, and the beginnings of our universe.
Why do professional astronomers speak of distances in the universe not in terms of light-years, but in terms of parsecs, a distance of 3.26 light-years? Explanation here.
The ecliptic is an imaginary line that marks the path of the sun. You can also find the planets and moon near this line, tracing the plane of our solar system.
The interstellar medium is the stuff between the stars. Made up mostly of hydrogen and helium gas, it contains all the material needed to make stars and planets. It is shaped by stellar winds, dying stars, galactic magnetic fields, and supernova explosions.
Chris Crockett got his Ph.D. in astronomy from UCLA in 2011 and worked at Lowell Observatory and the U.S. Naval Observatory. He then realized he enjoyed talking about astronomy a lot more than actually doing it. After being awarded a Mass Media Fellowship in 2013 by the American Association for the Advancement of Science, he spent a summer writing for Scientific American, then went on to become the staff astronomy writer at Science News from 2014 - 2017. These days, he freelances, focusing on stories about astronomy, planetary science, and physics. His work has appeared in Science News, Scientific American, Smithsonian Magazine, Knowable, Sky & Telescope, and the American Physical Society's online magazine Physics.