LIVE NOW

Time, beyond Earth.

A live almanac of clocks, calendars and gravity for sixteen worlds in our Solar System — eight planets, five major moons, three dwarf planets.

Open the clock → All sixteen worlds

Companion calculators

Run the numbers across sixteen worlds.

AGE

How old you would be on every planet.

Enter your date of birth, see your age in local years across sixteen worlds.

WEIGHT

What you would weigh in alien gravity.

Surface gravity from Mercury (3.7 m/s²) to Jupiter (24.79 m/s²) and beyond.

MARS SOLS

Your Mars-year birthday and live sol countdown.

A Martian sol is 24h 39m 35.244s. Calendar export for your next Mars-year turnover.

COMPARE

Two worlds, side by side.

Sol length, year length, gravity, radius — formatted as ratios you can quote.

METHODOLOGY

All clocks are propagated forward from the J2000.0 epoch using each body's published rotation and orbit. Body-local time divides one full sol into 24/60/60 — the same convention used in NASA mission control rooms.

READ THE METHOD →

SOURCES

Numbers we trust.

Rotation periods, orbital periods, axial tilts, and surface gravities come from the NASA Planetary Fact Sheets and the IAU 2015 rotational-element working group. Image credits and the full bibliography live on the How it works page.