What each cycle means
Jupiter return
Every 12 years or so, Jupiter finishes a full trip around the zodiac and comes back to the place it held when you were born. That happens near ages 12, 24, 36, 47, 59, 71, and 83. Astrology sees each return as the start of a new 12-year cycle of growth, often with a fresh appetite for learning and room to start something new.
Saturn square
Saturn takes about 29 and a half years to go around the zodiac. A quarter of the way around, and again three quarters of the way, it stands at a right angle to where it was at your birth: a square. The first one comes around age 7. Later ones fall about 7 years after each opposition and each return. In astrology, these squares are checkpoints. What you've built tends to be put to the test, and it's often a time for effort and adjustment.
Saturn opposition
Halfway through its cycle, Saturn sits directly across the zodiac from its position on the day you were born. The full cycle takes about 29 and a half years, so this happens around ages 15, 44, and 73. Astrology links the opposition with stepping back to see what you've built from the outside. It can also be a time of measuring yourself against what others expect of you.
Saturn return
Around age 29, again near 59, and once more near 88, Saturn comes back to the exact spot it was in when you were born. Each trip around the zodiac takes it about 29 and a half years. Astrologers see the return as a time for taking stock. It tends to call for maturity and responsibility, and for choosing what to keep and what to leave behind. The first one is often tied to stepping fully into adult life.
Uranus square
Uranus is slow: one full circle of the zodiac takes it about 84 years. Between the ages of 18 and 24, it first stands 90 degrees away from its place at your birth, and it does so again between about 61 and 64. Its speed changes along its orbit, so the exact ages depend on your generation. Modern astrology ties this square to a push for independence and change, and an urge to break away from whatever feels imposed on you.
Uranus opposition
Somewhere between ages 38 and 45, depending on your generation, Uranus has covered half of its 84-year trip around the zodiac and stands directly opposite where it was when you were born. It's one of modern astrology's best-known midlife moments, often linked with a wish to be more fully yourself and to change what no longer fits.
Neptune square
Neptune needs about 165 years to travel the whole zodiac, so in a lifetime it gets through only part of the circle. Around age 41, it has covered a quarter and forms a right angle with its position at your birth. Modern astrology reads this square as a time to question your ideals and illusions, and to look for new meaning.
Pluto square
Pluto's orbit is so lopsided that its pace through the zodiac varies widely over its roughly 248-year circuit. So the age of its square, a right angle to where it stood when you were born, depends on your generation. For people born between about 1940 and 2000, it falls somewhere between their mid-30s and early 50s, and later for anyone born after that. In modern astrology, it's linked to letting go of what has run its course.