When I tell people I’m interested in astronomy, I’m surprised to discover how many assume I mean astrology. Reactions fall into two categories. Some try to correct a perceived transgression of religious precepts. Others want to talk about their zodiac sign and ask about mine.

I understand the confusion. Both words, astronomy and astrology, came into the English language with histories that stretch back to a Latin root, astr-, which itself emerged from earlier Greek origins. Astr- means star. It appears in other English words. For example, an aster is a flower noted for its star shape. An asterisk is a common, star-like typographical symbol (*).

Although both words incorporate a linguistic component linking them to the stars, their meanings differ. Astrology contains a second root, -logy, which refers to words and speaking. You may be familiar with the word eulogy (eu+logy). Eulogy begins with eu-, which means “well or good.” A eulogy refers to speaking good things, typically in the form of making praise-filled remarks at funerals. This same ending, -logy, helps give meaning to the word astrology (literally, “star words” or “star speaking”). Astrology refers to the practice of trying to discern what stars are saying and how the message may apply to human destinies and ambitions.

Astronomy means something different. To its initial astr- (star), the word appends -nomy, which is based on a root word related to organizing and arranging. For comparison, you can find -nomy in the word “economy” (which originally related to household concerns—the eco- part, and their organization and arrangement—the -nomy part). The earliest astronomers were folks involved in the tasks of organizing and arranging celestial bodies. They created maps of the night sky, showing the names and locations of stars and constellations. They calculated anticipated occurrences of natural events, such as planetary positions and eclipses. Their heirs, modern-day astronomers, still study the positions, movements, and classifications of stars and star-like objects, although today they use many tools unknown to the ancients. Astronomers also investigate additional aspects of stars and other space phenomena, considering such details as physical properties, chemical compositions, interrelationships, gravitational effects, and life-cycles.

My own interests involve looking up at the night sky, learning to recognize its components, and marveling at the vastness of the universe. I like reading about new discoveries and how they sometimes lead to the reinterpretation of previously gathered evidence. I appreciate the guidance provided by experienced observers who serve as tour guides pointing out interesting items. I enjoy playing the role of tour guide myself. When I hear people gasp upon catching a first glimpse of Saturn’s rings, I know I have contributed to a moment that has literally taken their breath away.

The 12 zodiacal constellations familiar to those with an interest in astrology march across the night sky throughout the year, and people seem to have a special interest in seeing these famous star patterns. The zodiac occupies a region of the sky defined in reference to the sun’s apparent movement. As the Earth orbits the sun, the groups of stars a person can see looking out at night change. At the same time, the groups of stars that become invisible as sunlight floods the daytime sky also change. If you could draw a line marking the sun’s position against the background of distant stars, that line would form a circle that repeated itself every year. That imaginary line is called the ecliptic, and the zodiacal constellations comprise those that cross the ecliptic (along with a thirteenth, Ophiuchus, but his small intrusion into the set seems to be ignored by traditional astrologers).

I love astronomy, watching the stars and learning about the mysteries of outer space. After years of practice, I can recognize many constellations, including those of the zodiac. I cannot speculate regarding which ones some folks associate with certain personality traits or guess when they might consider it fortuitous to begin a new adventure. But I can report that the experience of standing under a dark, star-spangled sky helps me feel connected to eons of cosmic development, millennia of human wonder, and moments of profound peace.

Karen Bellenir has been writing for The Farmville Herald since 2009. Her book, “Happy to Be Here: A Transplant Takes Root in Farmville, Virginia” features a compilation of her columns. It is available from PierPress.com. You can contact Karen at kbellenir@PierPress.com.