Born on Mars? Here’s your Korean birth chart.
Saju, the Korean birth chart, turns the moment you were born into eight characters. It reads them from where the sun was on its yearly path and what time it was by the sun where you were born. Mars has the same sun, so we used the same rules on Mars.
Enter where and when you were born on Earth, in your local time, and pick a spot on Mars — and see the eight characters you’d have if you’d been born there at that moment, next to your chart on Earth.
- Sol:
- one Martian day, 24h 39m 35.244s long.
- Solar longitude (Ls):
- how far Mars has travelled around the sun since its spring equinox, from 0° to 360°.
- True solar time:
- the time by the sun’s position in the sky where you are, not by a clock.
Your Mars chart
PAL:JA is not affiliated with NASA.
Example: 28 September 2026, 12:00 UTC, Jezero Crater (77.45°E).
On Mars
On Earth you’re Wildflower 🌳. On Mars you’d be Jewel 💎.
Day Master: Jewel (辛), The Quiet Metal
= 2026-09-28 12:00 UTC
Same moment on Earth
Day Master: Wildflower (乙)
UTC clock time, no birthplace adjustment
Sep 28, 2026 · Ls 359.1°
Mars Year 39 begins
Right now on Mars
…
Five elements · On Mars
- Mars Sol Date
- 54297.2973
- Solar longitude (Ls)
- 359.08°
- Local Mars sun time
- 11:35
- Mars Year
- Mars Year 38
How does a Mars birth chart work?
It uses the rules of an Earth chart with the Martian sun: the year and months come from where Mars is on its path around the sun, and the day and hour come from the time by the sun at your spot on Mars.
Why is a Mars chart different from my Earth chart?
Mars days and years have different lengths. A sol is 24h 39m 35.244s, and a Mars year is 687 Earth days, so the same moment lands on different characters on the two planets.
How we did the math
This is a thought experiment built on real Mars astronomy. Here is every rule we used.
- Mars time. Your birth date and local time are first turned into UTC with your birthplace’s time zone, historical daylight saving included. Then the Allison & McEwen (2000) formulas give the Mars Sol Date (sols counted since 29 December 1873), the solar longitude Ls, and local true solar time at the longitude you choose — Jezero Crater, 77.45°E, unless you change it.
- Year. On Earth the saju year turns at Ipchun, when the sun reaches 315° on its yearly path. On Mars the year turns at the same point, Ls 315°. Mars Years are numbered the way planetary scientists count them, with Mars Year 1 beginning on 11 April 1955.
- Month. A new month every 30° of Ls, starting with the 寅 (Tiger) month at Ls 315°–345°. The month’s heavenly stem comes from the year’s stem, by the same rule as on Earth.
- Day. One sol is one day, and the day turns at local midnight by Mars sun time.
- Hour. The sol is split into twelve equal hours of 2h 3m 18s each; the 子 (Rat) hour runs from 23:00 to 01:00 by Mars sun time. The hour’s stem comes from the day’s stem, by the same rule as on Earth — and, as on Earth, the late Rat hour after 23:00 already takes the next day’s stem.
- Meaning. The characters are read with the same five elements and Day Master descriptions as an Earth chart.
Two starting points we chose
Mars has no calendar tradition to inherit, so two starting points are our own choice. The year that begins at the first Ls 315° of Mars Year 1 (4 December 1956) is counted as 甲子, and Mars Sol Date 0 is counted as a 甲子 day. Move either one and every Mars chart shifts.
A Martian day (sol) is 24h 39m 35.244s. A Mars year is 668.5991 sols, or 686.98 Earth days, so one 60-year cycle takes 60 Mars years — about 112.9 Earth years.
FAQ
Is a Mars saju chart real?
The astronomy is real and the rules are the same as an Earth chart, with two starting points we chose. It is a thought experiment, not a tradition, and like any saju chart it describes tendencies, not what will happen.
Why does the 60-year cycle take 113 years on Mars?
Because each of the 60 years is a Mars year of 686.98 Earth days: 60 of them add up to about 112.9 Earth years.
Why Jezero Crater?
It is a well-studied crater on Mars, so it makes a natural default birthplace. You can type any longitude from 0° to 360° east instead.