Planet Comparison Tool: Compare Time Across the Solar System
Use this planet comparison tool to compare how time works differently on any two planets. Compare Mars vs Earth, Jupiter vs Saturn, and see side-by-side comparisons of day lengths, year lengths, seasons, and planetary time differences!
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The Goldilocks Planet
The Almost-Twin
See how old you'd be on each planet!
Understanding Planet Comparisons
Comparing planets reveals fundamental differences in how time works across our solar system. Each planet's unique combination of orbital period, rotation rate, and axial tilt creates a completely different experience of days, years, and seasons.
Day Length Variations
Day length depends on rotation speed. Jupiter spins so fast that one day lasts less than 10 hours, while Venus rotates so slowly that one day takes 243 Earth days—longer than its year! Comparing these extremes helps us understand planetary dynamics.
Year Length Differences
Year length is determined by orbital distance and speed. Mercury completes an orbit in just 88 days, while Neptune takes 165 Earth years. When you compare Mars vs Earth, you see that Mars takes nearly twice as long to orbit (687 days vs. 365 days).
Popular Planet Comparisons
🔴 Mars vs Earth
The most important comparison for future space colonization. Mars has a 24.6-hour day (similar to Earth), but a 687-day year (1.88 Earth years). This means Mars seasons last nearly twice as long as Earth's, with spring alone lasting 7 Earth months.
Why it matters: Understanding Mars time is critical for planning agriculture, construction seasons, and daily life for future Mars colonists.
🪐 Jupiter vs Saturn
Both gas giants have extremely fast rotations (Jupiter: 9.9 hours, Saturn: 10.7 hours) but vastly different year lengths (Jupiter: 12 years, Saturn: 29 years). Comparing these helps us understand how mass and distance affect orbital periods.
Why it matters: Gas giant comparisons teach us about planetary formation and the outer solar system's dynamics.
☀️ Mercury vs Venus
Mercury has the fastest orbit (88 days) but a complex day-night cycle (176 days from sunrise to sunrise). Venus has a 225-day year but rotates backwards, taking 243 days for one rotation. Comparing inner planets reveals extreme diversity in planetary behavior.
Why it matters: Shows how tidal locking and retrograde rotation create bizarre time patterns close to the Sun.
What Planet Comparisons Teach Us
Comparing orbital periods demonstrates Kepler's Third Law—planets farther from the Sun take longer to orbit. Neptune's 165-year orbit vs. Mercury's 88-day orbit is a 686x difference!
Age comparisons show that time measurement is arbitrary and planet-specific. A 30-year-old on Earth is 124 on Mercury but only 2.5 on Jupiter. Time isn't universal—it's local.
Communication delay comparisons reveal the challenges of space exploration. Talking to Mars has a 4-24 minute delay (depending on positions), making real-time conversation impossible.
Comparing Earth to other planets highlights how perfectly balanced our planet is—moderate day length, regular seasons, habitable temperatures. No other planet matches Earth's time-friendly conditions.
Ready to Calculate Your Ages?
After comparing planets, discover your exact age on every world in the solar system.