Astrology has an extended historical past, stretching again 1000’s of years and permeating throughout quite a few historic civilizations. In trendy occasions, astrology is massive enterprise — and it is rising. In 2025, the business was estimated to be value round $3 billion.
On this excerpt from “What Science Says About Astrology” (Columbia College Press, 2026), writer and science journalist Carlos Orsi appears to be like at a research of 20 million those who sought to check whether or not star indicators have a task in romantic compatibility.
Essentially the most strong use of knowledge to check astrology is the research of affection indicators performed by David Voas in 2007, involving information from greater than 20 million folks from the 2001 census from England and Wales. Voas examined the speculation that sure solar indicators had been “extra appropriate” for romantic relationships.
Using the supposed romantic compatibility/incompatibility between indicators or planetary configurations to check astrology’s validity has an extended historical past. This technique was, for instance, employed by Carl Jung (1875–1967) in his work on astrology and synchronicity and within the traditional research by Bernie Silverman.
The concept of astrological compatibility or incompatibility in love has robust common enchantment. The guide “Love Indicators”, by Linda Goodman (1925–1995), an virtually 1,000-page tome, continues to be reprinted and bought 30 years after the writer’s dying (as of this writing, the latest version dates from 2020). Usually, indicators separated on the zodiac wheel by angles of 60° and 120° are thought of favorable for love, whereas these separated by 180° are seen as extraordinarily incompatible. Proper angles additionally are usually interpreted as unhealthy omens.
Voas explains the rationale of his research this manner: Folks born throughout the month-long durations outlined by a specific solar signal are purported to share sure inclinations, for instance, to be beneficiant or delicate or cussed. These tendencies have an effect on private relationships.
We all know from on a regular basis expertise in addition to a mass of social scientific information that people who find themselves comparable in age, schooling, social class, faith, ethnicity and so forth are way more more likely to marry than those that are completely different in these respects. {Couples} are thought to be being properly or poorly matched on the idea of look or persona. If astrological compatibility exists, its results ought to be observable.
This final level — that the results ought to be observable — is essential. Astrologers typically complain that checks primarily based solely on solar indicators are unfair as a result of a solar signal’s affect represents solely a fraction of a whole start chart’s that means. Nevertheless, a pattern of 20 million folks, like Voas’s, neutralizes this objection.
The research did reveal some anomalies — however after digging deeper this impact was defined by errors within the census information.
(Picture credit score: Crispin la valiente/Getty Photographs)
Even when the solar signal accounts for under, say, 0.1% of general romantic compatibility, in a pattern composed of 10 million {couples}, this could end in an extra of 10,000 shaped by folks with appropriate indicators, above and past what could be anticipated if astrology had no impact. Or, because the writer states, “With a sufficiently massive pattern, we must always be capable of detect any tendency for some indicators to draw or repel one another.”
The research’s preliminary aim was to seek out an extra of pairings between indicators deemed appropriate by the consensus of astrological literature. Sadly, Voas writes, such a consensus was arduous to seek out: “There is no such thing as a nice consistency amongst astrologers, and a survey of books and web sites reveals a substantial number of views regarding propitious pairings.” So he opted for the least frequent denominator, looking for any deviation from primary likelihood: “On this analysis I search for proof that any mixture of indicators is discovered roughly typically than could be anticipated to happen by probability.”
The outcomes had been at the least intriguing: The preliminary evaluation indicated an extra of {couples} the place each companions had the identical signal or adjoining indicators — e.g., extra Capricorns with Capricorns or Capricorns with Aquarians than anticipated. There have been about 22,000 additional {couples} with matching indicators past what probability would predict and an extra 5,000 {couples} with adjoining indicators. May this be astrology in motion?
Voas dug deeper into the info and found extra anomalies. For instance, the surplus of {couples} born in the identical month was even larger (23,000) than that of {couples} with the identical signal, and the proportion of {couples} with the identical start date was 41% increased than anticipated by probability. “Now whereas there could also be some people who find themselves drawn to one another as a result of they share a birthday, the surplus in all probability displays response error for essentially the most half,” he wrote. “Census varieties are sometimes accomplished by one member of the family, and that particular person might — by carelessness or forgetfulness — write in his or her birthday when coming into particulars for the partner.”
Different statistical anomalies attributed to errors embrace an extra of start dates recorded as January 1 (in all probability a placeholder when the precise date is unknown), cases of matching days in several months, and matching months with completely different days. Voas’s problem, then, was distinguishing these potential information entry errors from any actual astrological impact — if one existed.
“The partial overlap between astrological indicators and months of start permits an important take a look at,” he wrote, noting that the primary 10 days of the interval lined by any signal falls in a single month whereas the opposite 20 or so fall within the subsequent (for instance, Aries runs from March 21 to April 20). So was an individual born within the final days of March extra more likely to be married to somebody born within the early weeks of March or maybe the early weeks of April? Within the first case, their partner could be from the identical month however a unique signal; within the second, from a unique month however the identical signal.
“The outcomes had been conclusive. The {couples} whose birthdays belonged to the identical signal however fell in several months had been no extra quite a few than probability would dictate. In contrast, there have been extra mixtures of birthdays from completely different components of the identical month than anticipated. This extra in shared months of start might be the results of response error, however in any occasion solar signal shouldn’t be an element.”
The slight extra of {couples} with adjoining indicators was defined by a data-imputation method used within the British census to fill in lacking or illegible information. One companion’s start date was imputed as the primary day of a month and the opposite’s as the primary of the next month. When these imputed information factors had been excluded from the pattern, the “adjoining signal” impact disappeared. The underside line is that an evaluation of 10 million {couples} in England and Wales revealed no astrological impact.
However Voas’s work illustrates how simple it’s to get misplaced in information or be swayed by enthusiasm. Somebody who had stopped at step one — discovering an extra of {couples} with the identical signal — may need mistakenly offered census information as validation for astrology.
This text is excerpted from What Science Says About Astrology by Carlos Orsi. Copyright (c) 2026 Columbia College Press. Utilized by association with the Writer. All rights reserved.
Columbia College Press
What Science Says About Astrology
This guide goals a scientific lens at astrology, from its colourful historical past to experimental checks of its predictions by the social and psychological components that specify its enduring recognition.
