ASTROTIME — Universal, Relativistic & Planetary Clocks
What time is it on Mars right now? How far ahead is a clock on the Moon? What
does your Unix timestamp look like in binary? AstroTime answers all of this —
beautifully, in real time.
━━━ 8 TIME SCALES, ALL AT ONCE ━━━
🌍 UTC — Coordinated Universal Time
The global civil standard. Includes your local timezone alongside UTC, and the
current Solar Longitude (Ls) of Earth in its orbit.
⚛️ TAI — International Atomic Time
The output of ~450 cesium clocks worldwide. Ahead of UTC by exactly 37 leap
seconds — with an animated historical timeline of every leap second since 1972.
🌌 TDB — Barycentric Dynamical Time
The relativistic clock at the solar system's centre of mass. Shows the periodic
±1.657 ms correction caused by Earth's orbital eccentricity — visualised as a
live sinusoidal curve.
🌕 LTC — Lunar Coordinate Time
Time on the Moon's surface. Clocks tick faster on the Moon due to weaker gravity
(+58.7 µs/day, ITU 2024). Displays accumulated relativistic drift since J2000,
current lunar phase, and all 8 phases of the synodic cycle animated in real time.
🔴 MTC — Coordinated Mars Time
Time at Mars's Prime Meridian (Airy-0 crater), calculated via the NASA Allison &
McEwen algorithm. Shows current Sol, Mars Year, Solar Longitude Ls, and an
animated dual-orbit diagram of Earth and Mars around the Sun.
💻 Unix Epoch
Seconds since 1970-01-01. Includes a live 32-bit binary representation of the
timestamp and a visual countdown to the Y2038 overflow problem.
🔭 GAST — Greenwich Apparent Sidereal Time
Earth's rotation angle relative to the distant stars. Visualised as a rotating
celestial sphere with the vernal equinox pointer (♈ Aries) moving in real time.
🌐 Internet Time (.beats)
Swatch's timezone-free decimal clock. One .beat = 1 min 26.4 s. Displayed on a
1000-division animated dial — the same moment everywhere on Earth.
━━━ KEY FEATURES ━━━
⏳ TIME TRAVEL
Enter any date and time — a birthday, a historical event, a future eclipse — and
watch all 8 clocks instantly recalculate. Includes quick offsets (±1 day, ±1 year)
and a live banner showing the moment you're exploring.
🪐 ANIMATED ORBIT DIAGRAMS
Each planetary clock includes a full-screen Canvas animation:
• Earth orbiting the Sun with current orbital position
• Moon orbiting Earth with correct phase shading and 8-phase strip
• Mars and Earth orbits compared side by side
All orbits show the correct counterclockwise rotation direction.
📖 IN-DEPTH EXPLANATIONS
Every clock includes a collapsible "About" panel with the physics, history, and
real-world use of each time scale — from Einstein's relativity to NASA mission
planning to the Y2038 computer crisis.
🌟 SPACE-THEMED DESIGN
Animated starfield background, shooting stars, per-planet accent colours, and a
dark space aesthetic built for OLED screens.
━━━ WHO IS IT FOR? ━━━
• Space enthusiasts and amateur astronomers
• Software developers curious about time systems
• Students studying physics, relativity, or planetary science
• Anyone who ever wondered what time it is on Mars
━━━ PERMISSIONS ━━━
None. AstroTime requires no permissions, no account, no internet connection after
first load. All calculations run entirely on your device.
━━━ TECHNICAL NOTES ━━━
All time calculations use published scientific formulae:
• MTC: Allison & McEwen (2000), NASA
• LTC drift: ITU recommendations (2024)
• TDB: Fairhead & Bretagnon (1990)
• GAST: IAU 1982 GMST formula
• Solar Longitude: standard equation of centre