Solar
Return

A solar return is the moment the Sun gets back to the ecliptic longitude it occupied at your birth, to the second of arc. It happens once a year, within a day or two of your birthday, and the chart cast for that moment is read for the twelve months until the next one.

The older name is the revolution of the year of the nativity, or simply the solar revolution: the Latin revolutio translates the Arabic taḥwīl. Abu Ma'shar (787–886), a Persian astrologer who worked in Baghdad, wrote a long work on it, On the Revolutions of the Years of Nativities, translated from the Arabic by Benjamin Dykes as Persian Nativities IV. His book treats the revolution together with profections, the distribution of the bounds and the firdaria.

In the seventeenth century Jean-Baptiste Morin de Villefranche gave Book 23 of his Astrologia Gallica to solar and lunar revolutions. His first rule is still the usual caution: a revolution should not be read as promising anything significant that the birth chart and its directions do not already indicate. Modern practice mostly keeps that order: the return chart is read on its own (its Ascendant, the planets on its angles, the house the Sun falls in, the Moon) and then laid over the birth chart. Not everyone insists on the second step. Mary Fortier Shea, who wrote two books on solar returns, found that most of what the comparison shows is already visible in the return chart alone.

The steps below are what the code does; the methodology page covers the ephemeris and the time zone handling that all the calculators share.

1. Birth moment. Your birth date and clock time are converted to Universal Time with the IANA time zone database, which carries each place's history of offsets and daylight saving.
2. Birth Sun. The Sun's apparent geocentric longitude at that moment comes from our ephemeris, measured from the true equinox of date as in the birth chart. The search uses the full-precision value: rounded to four decimals, as a chart's planet list shows it, the Sun's position could move the return by up to about four and a half seconds.
3. The return. A search for the moment the Sun returns to its birth longitude starts five days before the expected date and moves forward until the Sun's longitude equals the birth value. It converges to well under a millisecond.
4. The chart. Planets and houses are computed for the return moment, rounded to the nearest second, at your birthplace or at the place you choose. The Ascendant and Midheaven are the true angles from the house routine, not the first and tenth house cusps; in Whole Sign houses those cusps sit at 0° of a sign. You can choose Whole Sign (the default), Placidus or Equal houses. Placidus is undefined beyond about 66.5° north or south, so there the chart falls back to Whole Sign with a note.
5. Times. The moment is shown in Universal Time and in local clock time at the chart's place, with the offset that applied that day, daylight saving included. For a relocated chart it is also shown in your birth time zone.
6. Returns of the slow planets. Mercury through Saturn have no ready-made crossing routine, so the code steps through their positions, splits each step at any station, and bisects every crossing of the birth degree to about a tenth of a second.

Which return belongs to a year

The return for a year is the one in that year's birthday season: the 10th return after birth is the one for your birth year plus 10. Usually that is obvious, but not on the turn of the year. Take a birth at 12:30 AM on January 1, 1990, in Tokyo, which was 3:30 PM UTC on the day before. The return for 2026 came at 6:16 PM Tokyo time on December 31, 2025. A search that started on January 1 of 2026 would miss it and land on the return of January 1, 2027, which belongs to 2027. The calculator counts returns from the birth instead, so this cannot happen.

The script that builds this page checked 16 of the API's return moments against the same crossing search run outside the API and against a separate bisection of the Sun's longitude; the largest difference was 0.0031 seconds.

Tropical, not precession-corrected

Some astrologers, mainly from the sidereal tradition, add the precession of the equinoxes since birth to the birth Sun, about 50.3 arcseconds a year, before searching. The calculator does not. For the worked example below that correction would be 49.4 arcminutes and would move the return 20.7 hours later, to 10:18 PM that evening, with the Ascendant at 14°24′ Aries instead of 10°56′ Gemini. Mary Fortier Shea compared both kinds over many years and kept the uncorrected tropical chart, on the grounds that precession is a sidereal concept.

The Sun comes back to the same longitude after a tropical year, 365.2422 days on average, about 5 hours 49 minutes more than a common year. So each return falls roughly six hours later by the clock than the one before, until a February 29 drops the calendar back a day. Barack Obama's returns, cast for Honolulu, show the pattern:

Each return came 365 days plus 5 hours 34 minutes to 5 hours 53 minutes after the one before. The step varies by some minutes because the Moon and the planets pull the Earth a little off its average track, and the equinox that longitudes are measured from nods back and forth (nutation). Six hours turns the sky about 90°, so the return Sun usually lands about three houses earlier each year. Shea describes the result: years of the Sun in angular houses, then succedent, then cadent.

Across the four-year leap cycle the return comes slightly earlier on average, because from 1901 to 2099 the calendar year averages 365.25 days, 11.2 minutes longer than the Sun's. Shea also notes a 33-year near-repeat: 33 tropical years are within minutes of 33 calendar years with eight leap days, so the return comes back close to the birth time. Obama's 33rd return, in 1994, came at 6:40 PM, 44 minutes before his 7:24 PM birth time, with the Ascendant at 5°38′ Aquarius against 18°03′ Aquarius at birth; by his 66th, in 2027, the gap had grown to 83 minutes.

Barack Obama was born at 7:24 PM on August 4, 1961, in Honolulu, according to his birth certificate; that was 5:24 AM UTC on August 5, 1961. His birth Sun was at 12°32′ Leo, or 132.547924° of longitude. Entered in the calculator with 2020 as the year and the default Whole Sign houses, it gives his 59th return:

The return fell at 1:38 AM on the morning of his birthday, Honolulu time. With Gemini rising, the reading below for that sign applies, and the Sun in the 3rd house puts the year's effort into the matters of that house: writing, speaking, short trips, the immediate circle. The Moon in Aquarius in the 9th house adds study, travel and publishing to the year's concerns. The closest aspect, Mars square Jupiter, was exact to 0°01′. No planet stood within 5° of an angle, so the chart has no angular emphasis. The example shows how to read the chart; it makes no claims about his year.

The same moment cast elsewhere

Relocating changes only the angles and houses. The same instant was 7:38 AM EDT in Washington, D.C., where 28°44′ Leo was rising. In Honolulu Whole Sign and Placidus put every planet in the same house; in Washington they do not:

In Washington the Sun at 12°32′ Leo is in the rising sign, so Whole Sign counts it in the 1st house, but it is 16° short of the Ascendant degree, still above the horizon, which Placidus counts as the 12th. Neither is a calculation error; they are two conventions, and the calculator states which one it used. Whether to relocate at all is an old debate. Morin allowed that traveling for the time of the revolution changes it; Shea treats the birthplace chart, the chart for where you live and the chart for where you are at the return as three different, usable charts.

The Sun is not the only body that comes back. Jupiter returns to its birth longitude about every 11.9 years and Saturn about every 29.5, and astrologers read those returns as markers of the life cycle, Saturn's near ages 29, 59 and 88 especially. The calculator lists yours to age 100 with every pass, in the time zone of the chart's place. A planet that turns retrograde near its birth degree crosses it three times: forward, back, and forward again. For Barack Obama, with Jupiter at 0°51′ Aquarius and Saturn at 25°19′ Capricorn at birth:

His 5th Jupiter return, on December 23, 2020, fell inside the 2020 solar-return year, two days after the conjunction of Jupiter and Saturn at 0°29′ Aquarius on December 21, 2020, 0°22′ from his birth Jupiter. Saturn had come back on February 3, 2020 and crossed only once: when it turned direct on September 29, 2020 it stood at 25°20′ Capricorn, just 23 arcseconds short of crossing back over his birth Saturn. Stations this close to a birth degree are why the calculator locates each station before looking for crossings: a search that only compares positions a day apart can miss two crossings that fall between its samples.

Between the 2020 return and the next, these planets came back to their birth degrees: Mercury on August 5, 2020, Venus on August 9, 2020, Jupiter on December 23, 2020, Venus on June 3, 2021, Mercury on July 28, 2021. Mercury and Venus do so about once a year, Mars about every two. The result lists the same for your year.

The notes below follow the common modern reading: the return Ascendant sets the tone of the year, the Sun's house shows where the year's effort goes, the Moon describes its day-to-day concerns, and planets on the angles stand out. Shea gives more weight to a planet's house than to its sign, because in a return most signs repeat on fixed cycles: the Sun never moves, Mercury stays within a sign of it, Venus comes back to nearly the same place every eight years and the Moon every nineteen. Obama's returns bear that out: Venus at 27°20′ Gemini in 2012, 27°10′ Gemini in 2020, 27°02′ Gemini in 2028; the Moon at 19°35′ Aquarius in 2001, 22°13′ Aquarius in 2020, 21°24′ Aquarius in 2039. The notes are interpretation, offered as tendencies, and the result shows the full text for your chart.

The Ascendant of the return, sign by sign

The return Sun, house by house

• Abu Ma'shar, On the Revolutions of the Years of Nativities, translated from the Arabic by Benjamin N. Dykes as Persian Nativities IV (Cazimi Press, 2019): solar revolutions among the other annual techniques.
• Jean-Baptiste Morin, Astrologia Gallica (The Hague, 1661), Book 23, Revolutions, in James Herschel Holden's English translation (American Federation of Astrologers): the rules for judging solar and lunar returns.
• Mary Fortier Shea, Solar Returns: A Study (Twin Stars Unlimited, 2000), on tropical, sidereal and precessed returns, on the choice of location, and on the Sun's movement through the houses; and her Planets in Solar Returns (ACS, 1992).
• Ray Merriman, The New Solar Return Book of Prediction (Seek-It Publications, 1998), another modern handbook of the technique.
• The site's methodology page, for the ephemeris's date range (1800 to 2399) and accuracy, time zones and aspect orbs.