Extraordinary ClaimsAnswer
What does research say about people who report memories of past lives?
What past-life memory research investigates, what reported matches can show, and why case studies do not by themselves establish reincarnation.
THE QUESTION LIBRARY EXTRAORDINARY CLAIMS
Does astrology work? What happens when it is tested?
Nearly 3 in 10 Americans consult astrology or a horoscope at least once a year, so here is what happens when its predictions are put to fair, blind tests.
THE SHORT ANSWER
No. When astrology’s predictions are tested fairly, they do no better than guessing. In a 1985 double-blind test published in Nature, astrologers picked the right personality profile for a birth chart about one time in three, about what chance gives. A study of 2,101 people born minutes apart found none of the likenesses astrology predicts. Horoscopes feel accurate because general statements fit almost anyone. Many people enjoy astrology just for fun, and that is their choice.
- In a 1985 test in Nature, astrologers’ first picks matched 40 of 116 birth charts, close to the one in three expected by guessing.
- A study of 2,101 people born in London in March 1958, on average 4.8 minutes apart, found no astrological likeness across 110 traits.
- In 1949, 39 students rated one shared sketch, taken largely from an astrology book, 4.26 out of 5 for fitting them.
- Earth’s slow wobble means the Sun no longer lines up with the same constellations on the same dates as 3,000 years ago.
- In a 2024 Pew survey, 27% of U.S. adults said they believe in astrology, and most who use astrology, tarot or fortune tellers say they do it for fun.
About this picture
A southern-sky chart from Andreas Cellarius’s 1660 star atlas. Its zodiac figures include Scorpio, Sagittarius and Capricorn. At top left, the legs of Ophiuchus (labeled “Serpentarius Ophiuchus”) stand on Scorpio. The Sun passes through Ophiuchus too, but the zodiac leaves it out.
WHERE THE EVIDENCE STANDS
How sure are we?
- Birth charts can describe a person’s personality or predict their life.Carlson’s 1985 double-blind test in Nature (40 of 116 first picks right, chance is one in three); Dean and Kelly 2003: 2,101 time twins showed an effect of 0.00, and 40-plus matching studies were not reliably better than chance.
- Horoscopes feel accurate because general statements seem to fit almost everyone.Forer 1949: 39 students rated one identical sketch, drawn largely from an astrology book, 4.26 out of 5; Dean and Kelly list this Barnum effect among the hidden persuaders that create false hits; the Corsini Encyclopedia of Psychology describes it as a general tendency that Forer first documented.
- The zodiac signs no longer line up with the constellations they were named for.NASA: Earth’s axis has shifted since the Babylonians set up the signs over 3,000 years ago, and the Sun passes through 13 constellations; precession takes about 25,770 years per cycle.
- Mercury retrograde affects people’s lives.NASA’s StarChild: retrograde motion is only apparent, caused by how Earth and the planet move; the Planetary Society says there is no scientific evidence it affects anyone.
- A later reanalysis shows the 1985 Nature test really supported astrology.Ertel’s 2009 reanalysis found a borderline result (p = .054) when first and second picks are counted together, but he wrote that it was not enough to count astrology as verified.
WHAT WE DON’T KNOW YET
No test can prove an effect is exactly zero, so very tiny effects can never be fully ruled out. Researchers have also disagreed for years over the Gauquelin “Mars effect.” Why many people find astrology fun or helpful is a separate question that research has only begun to measure.
WHAT WOULD CHANGE THIS ANSWER
Astrologers matching charts to people clearly better than chance, under blind conditions, in repeated tests by independent teams would change this answer. So would time twins turning out to be more alike than strangers.
No. When astrology’s predictions are put to fair tests, they do no better than guessing. That is the plain answer. But it is worth seeing why so many people feel that astrology works, because that feeling is real.
Astrology is very old. According to NASA, the Babylonians, who lived more than 3,000 years ago, split the band of sky that the Sun seems to travel through into 12 equal parts, one for each month. Today, about 3 in 10 U.S. adults consult astrology, tarot cards or a fortune teller at least once a year, a 2024 Pew Research Center survey found. Most of them say they do it just for fun. NASA notes that astrology matters to some cultural traditions, but that its claims are not based on scientific evidence.
Here is what the tests show. In 1985, the journal Nature published a double-blind test. In a test like this, nobody taking part or running it knows the right answers until the end. Astrologers got a birth chart and three personality profiles, and had to pick the profile that belonged to the chart’s owner. Their first picks were right 40 times out of 116, about one time in three. Guessing gives one in three. A later study followed 2,101 people born in London in March 1958, on average less than five minutes apart. Astrology says they should be alike. Across 110 traits, they were not.
So why does a horoscope feel so personal? In 1949, a psychologist gave 39 students a “personal” sketch that was the same for everyone. Most of it came from an astrology book. On average, the students rated how well it described them at 4.26 out of 5. This is called the Barnum or Forer effect: general statements feel made for us.
Enjoying astrology is a personal choice, and nothing here mocks it. The question this page answers is narrower: does it predict? The evidence says it does not.
THE LONG ANSWER
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Keep asking
Next on the path “Astrology, psychics, awakening: what holds up?” · step 3 of 8
Do psychic abilities like telepathy or seeing the future hold up when tested?
Not so far, by the standard of independent labs repeating a result.
See this path: Astrology, psychics, awakening: what holds up?
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God Plays Dice answers big questions in plain words, with sources and one of six honest labels.
Words worth knowing (6)
- Birth chart
- A map of where the Sun, Moon and planets were at the moment and place of a person’s birth. Astrologers read it to describe a person.
- Double-blind test
- A test in which neither the people taking part nor the people judging the results know which answer is the right one, so hopes and hints can’t steer the result.
- Barnum or Forer effect
- The tendency to accept general statements that fit almost anyone as a special description of ourselves. It was shown in a classroom test by psychologist Bertram Forer in 1949.
- Time twins
- Unrelated people born at nearly the same time and place. Astrology predicts they should be alike, which makes them a strong test.
- Precession
- The slow wobble of Earth’s axis, like a spinning top. NASA puts one full cycle at about 25,770 years. It shifts which stars line up with the Sun on a given date.
- Apparent retrograde motion
- When a planet seems to move backward across the sky for a while. It is an effect of our viewpoint from a moving Earth, not a real change in the planet’s path.
Sources & further reading
(10) · Checked Sep 26, 2026
- A double-blind test of astrology (Shawn Carlson) ↗Nature 318, 419–425 (published Dec. 5, 1985), doi:10.1038/318419a0Two double-blind tests of whether natal charts describe personality. The article page shows only the abstract; the design and counts (116 charts, three CPI profiles each, first picks 40 right; 83 volunteers choosing among three chart readings) were read from Carlson’s tables as reproduced in Ertel (2009).
- Is Astrology Relevant to Consciousness and Psi? (Geoffrey Dean and Ivan W. Kelly) ↗Journal of Consciousness Studies 10, no. 6–7 (2003): 175–198Time twins: 2,101 people born in London March 3–9, 1958, on average 4.8 minutes apart, 110 variables at ages 11, 16 and 23, effect 0.00 ± 0.03; 40-plus matching studies (nearly 700 astrologers, 1,150 charts) mean effect 0.051, p = 0.66; 10 studies (nearly 300 people) choosing own reading, 0.002; 25 agreement studies (nearly 500 astrologers), 0.101; Barnum effect among hidden persuaders; sun sign and extraversion link vanished without prior knowledge; Gauquelin data and parents adjusting birth times; tiny effects near 0.01 can’t be ruled out. Full text read from the PDF copy at https://journalpsyche.org/articles/0xc062.pdf (the publisher page returns HTTP 403 to scripted requests; its metadata was confirmed from the Internet Archive copy of Feb. 8, 2026). Kelly: Department of Educational Psychology, University of Saskatchewan.
- The fallacy of personal validation: a classroom demonstration of gullibility (Bertram R. Forer) ↗Journal of Abnormal and Social Psychology 44, no. 1 (1949): 118–123The classic Barnum/Forer study (the 1949 title’s wording is Forer’s, not ours): 39 students in his introductory psychology class; identical 13-item sketch; statements “came largely from a newsstand astrology book”; sketch ratings 0 to 5 (one 2, four 3s, eighteen 4s, sixteen 5s, a mean of 4.26); mean acceptance 10.2 of 13 items. Read from the scanned copy hosted by Astronomy magazine (https://www.astronomy.com/wp-content/uploads/2024/01/Forer-fallacy-of-personal-validation-1949.pdf); the mean of 4.26 is computed from his Table 1 (166/39). The effect’s names: The Corsini Encyclopedia of Psychology entry “Barnum Effect” (Bernard C. Beins, 2010, doi:10.1002/9780470479216.corpsy0108) defines it as the tendency to accept vague, generally positive statements as unique to oneself and credits Forer (1949) with first documenting it systematically; a 2018 Springer chapter by Jonathon Howard is titled “Forer Effect” (doi:10.1007/978-3-319-93224-8_9).
- Appraisal of Shawn Carlson’s Renowned Astrology Tests (Suitbert Ertel) ↗Journal of Scientific Exploration 23, no. 2 (2009): 125–137Reanalysis: first-plus-second picks 86 of 116 vs 77.3 expected, p = .054, and a rating analysis at p = .037; astrologer adviser Teresa Hamilton quoted as never satisfied the test was fair; results “insufficient to deem astrology as empirically verified” but Carlson’s verdict called untenable; Gauquelin effects described as separate from classical astrology.
- 30% of Americans Consult Astrology, Tarot Cards or Fortune Tellers (Chip Rotolo) ↗Pew Research Center (May 21, 2025)Survey of 9,593 U.S. adults, Oct. 21–27, 2024: 30% consult astrology, tarot or a fortune teller yearly; 28% astrology or a horoscope; 27% believe in astrology (29% in 2017, an identical question); 27% of the religiously affiliated vs 28% of the unaffiliated; women 35% vs men 18%; 20% mostly for fun vs 10% for insights; 1% rely a lot on them for major decisions.
- Constellations and the Calendar ↗NASA (Sept. 20, 2016; adapted from NASA Space Place)Babylonians over 3,000 years ago divided the zodiac into 12 equal parts; left out Ophiuchus though the Sun passes through 13 constellations; Leo birthdays about July 23 to Aug. 22 then; Earth’s axis has shifted; Virgo 45 days vs Scorpius 7; “we just did the math.” NASA Space Place’s current page (https://spaceplace.nasa.gov/starfinder2/en/, updated July 31, 2026) says astrology is important to some cultural traditions but its claims are not based on scientific evidence. Precession figure from NASA Science, “Milankovitch (Orbital) Cycles and Their Role in Earth’s Climate” (https://science.nasa.gov/science-research/earth-science/climate-science/milankovitch-orbital-cycles-and-their-role-in-earths-climate/): Earth wobbles like a spinning toy top, and the cycle of axial precession spans about 25,771.5 years.
- What does it mean for Mercury to be in retrograde? ↗NASA Goddard StarChild (Question of the Month, June 2002)Retrograde motion is an apparent change; the planet does not move backward in its orbit; it happens when a faster planet catches up to and passes a slower one; the walking-friend demonstration.
- What does “Mercury in retrograde” actually mean? (Kate Howells) ↗The Planetary Society (April 19, 2023)Mercury orbits in 88 days and overtakes Earth three to four times a year, appearing to move backward for about three weeks; no scientific evidence that any planet’s apparent retrograde motion affects you.
- Michel Gauquelin (1928–1991) ↗The Urania Trust (an astrology education charity)Identifies Michel Gauquelin as a French statistician who tested whether astrology’s claims could be validated, and credits him with the finding about Mars in champion athletes’ charts. Used only for his name and field; the evidence for and against the Mars effect comes from Ertel (2009) and Dean and Kelly (2003).
- Precession of the Equinox ↗Encyclopedia of Occultism and Parapsychology (Gale), via Encyclopedia.comMost Western astrologers use the tropical zodiac, with 0° Aries at the Sun’s position at the spring equinox; some use a sidereal zodiac tied to the constellations. Used here only to describe astrologers’ own practice fairly.
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