Why this test exists
Astrology attracts two kinds of bad information at once. There is the credulous kind, where anything vaguely cosmic is repeated without checking, and there is the debunking kind, where a real astronomical fact is aimed at a claim nobody actually made.
The thirteenth sign story is the clearest example. Every few years a headline announces that NASA has changed the zodiac and everyone's sign has shifted. The underlying astronomy is correct, precession is real and the constellations have moved. The conclusion does not follow, because Western astrology has been explicitly measured from the equinox rather than the stars for two thousand years. Both the excited version and the smug version get it wrong.
What counts as an answer here
Every question on this page has a checkable answer. None of them ask what a sign means or whether astrology works, because those are not questions a quiz can settle.
What they ask is whether Mercury physically reverses, how long Uranus spends retrograde, whether the signs are equal in length, when the Chinese year starts. Those have answers you can verify against an ephemeris or a calendar, and this site computes most of them elsewhere.
The one about gravity
The last question is worth flagging because it cuts both ways. The gravitational objection is entirely correct as physics: the doctor holding a newborn exerts more gravitational force on it than Mars does, and it is not close.
But it is aimed at a claim most astrologers do not make. Traditional astrology treats planetary positions as signs rather than causes, in the way that a clock does not cause the time. Whether that framing rescues astrology is a separate argument and not one this page tries to settle. What it does mean is that refuting the gravity version refutes something almost nobody is defending.
If you got a low score
Most people do, and the questions were chosen for that. Several of these are repeated on large astrology sites and in newspaper science columns alike.
Each answer links to the page on this site that computes the thing in question, so you can check it rather than take our word for it. That is the entire point of the site, and this test is the shortest version of it.
Questions people ask about this
Is Mercury retrograde real?
The apparent motion is entirely real and computable to the minute. The backwards movement is not: Mercury continues forward around the Sun throughout, and the reversal is a matter of the angle we view it from as Earth overtakes it.
Did NASA add a thirteenth zodiac sign?
No. NASA published an educational page noting that the Sun passes through Ophiuchus, which is an astronomical fact and has been known for millennia. It made no statement about astrology and changed nothing.
Has my star sign changed because of precession?
Not within Western astrology, which measures from the March equinox rather than the constellations and so is unaffected. In sidereal astrology, used in the Indian tradition, your sign is usually one earlier, and that has always been the case rather than being a recent change.
Are cusp signs real?
No. The Sun occupies one exact longitude at any moment and that longitude falls inside one sign. What people call a cusp is a birthday close enough to a boundary that the date range they were given cannot settle it.
Do the planets affect us through gravity?
Not measurably, and serious astrology does not claim they do. The gravitational force from the midwife exceeds that from Mars by a wide margin. Astrology reads positions as symbolic rather than causal, which is a different claim and a different argument.
Where do the answers come from?
Each one links to the page on this site that computes it, and those computations are checked against Swiss Ephemeris. Nothing on this test rests on an opinion about what astrology means.