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Black Holes to Blackboards: In the Seventh House of Saturn

Jeffrey F. Lockwood
Saguaro High School

Hi, I’m an Ophiuchi.

A sophomore walked up to the registration table to sign up for next year’s class. “I’d like astrology, fifth period,” she said.

Smiling, I said, “You mean astronomy, don’t you?”

“No,” she replied, a quizzical look on her face. “I mean astrology.” Then she added, “What’s the difference anyway?”

I would imagine that every astronomy teacher of the last four centuries has had this conversation at least once. Rooted deeply in ancient Mesopotamian, Greek, Chinese, Roman, and Arabic cultures, astrology continues to be prevalent in our modern society as both a belief and a form of entertainment. Its fascination for students is an opportunity for teachers to discuss what science is.

In my experience, the confusion between the pseudoscience of astrology and the science of astronomy arises from the similarity of their names and the references to stars, planets, Sun, and Moon inherent in horoscopes. Students’ acceptance of astrology is not really a misconception, because this would imply a firmly held, mistaken belief based at least in part on personal observation and experience. Astrology is, instead, an idea grounded in speculation, opinion, and ignorance–a case of mistaken identity. The correct definitions of astronomy and astrology need to be discussed in the classroom; students need to understand the difference between the application of astrological tenets to explain worldly events and the process of scientific problem-solving.

To find out how strong a grip astrology has on students, I took a simple survey at my school. I prepared a questionnaire that asked students whether they knew their signs and believed in astrology. To compare their knowledge of astrology to that of astronomy, I also asked a few basic astronomy questions. I polled 100 ninth- and tenth-grade biology students and 100 eleventh- and twelfth-grade physics students.

To my surprise, not all the students knew their signs: 24 of the younger students and 9 of the older ones did not give their signs. A quarter of the younger and a third of the older students said they accepted that “the position in space of the Sun, Moon, and planets at the moment of your birth influences your personality or your destiny in some way.” Over half of both groups said they read an astrological column in a newspaper or magazine regularly–10 percent daily, 15 percent weekly, a third monthly.

I also asked the students how many planets are in the solar system and where Earth comes in the sequence. Thirty-four percent of the younger students and 15 percent of the older ones missed at least one of these questions. (Results were undoubtedly skewed by the popularity of the sitcom Third Rock From the Sun.) When I asked how far Earth is from the Sun, 3 percent of the younger and 23 percent of the older students responded with a correct or approximately correct answer. The incorrect answers ranged from 1,000 miles to a mole of light-years (6.02 ­ 1023).

These results are broadly consistent with surveys of college students and adults [see "The Roots of Astrology," September/October 1994, p. 21]. If anything, the surveys suggest that acceptance of astrology increases with age. This isn’t surprising when the science curriculum does not address astrology and other pseudosciences.

Teachers can draw on various techniques to encourage students to examine these beliefs and learn a scientific way of thinking. One is to build the Project STAR celestial sphere. It comes with a zodiac strip, which students tape onto the ecliptic line of the sphere. After students draw in the constellations on the sphere, they almost always notice that the Sun is not in the appropriate astrological constellation on their birthday. They also notice that the Sun is in some constellations for longer than 30 days and in others for only a couple of weeks. Because of the slow shift of Earth’s axis, the Sun now passes through 13 constellations, not the 12 known to the ancient Greeks. The “new” sign, Ophiuchus, corresponds to the position of the Sun from Thanksgiving to Dec. 10.

Another popular activity is to find an astrology book that summarizes personality types and have students pick their profile out of the collection of 12. I then have them try to pick out the description of their girlfriend, boyfriend, or a family member. Letting students examine the previous month’s horoscope, taken from one of the many magazines for teens, is another good way to show the generalities in such “predictions.”

“Your Astrology Defense Kit,” a section in Project ASTRO’s Universe at Your Fingertips activity manual, is filled with fun discussion material such as the “Ten Embarrassing Questions” about astrology and Andy Fraknoi’s “jetology” analogy. Although these activities are not as open-ended as classroom research can be [see Black Holes to Blackboards, September/October 1995, p. 8], they do involve inquiry and critical thinking, the quintessence of science.

Newtonian science, firmly rooted in rational cause-and-effect explanations, has rendered astrology obsolete as an explanation of the natural world. Even post-Newtonian quantum physics, which has profoundly changed scientists’ views of cause and effect, leaves no room for astrology. Along with other pseudosciences, astrology is worth addressing if only to allow students to learn the process of scientific analysis by looking at an example of the opposite: an unfounded and unproven amalgamation of rhetoric and symbolism. Approaching the subject in the classroom with a bit of whimsy will help students to understand astrology for what it is: a (mostly) harmless form of amusement, similar to in many ways to another social phenomenon, the World Wrestling Federation.

Uh-oh…just read my horoscope and it says that today is a bad day for mental activities, and that my intellectual faculties will be enhanced by the positioning of Saturn in my second house during the next full Moon. So I must stop writing now.

JEFFREY F. LOCKWOOD is a high-school and college astronomy and physics teacher at Sahuaro High School and Pima Community College in Tucson, Ariz. His email address is

The fall 1988 issue of The Universe in the Classroom newsletter, “Horoscopes vs. Telescopes,” is available on line at (or 11sp.html for the Spanish version).