About Cosmic Travel Time & Relativistic Spaceflight Calculator
Interstellar and interplanetary spaceflight mission duration calculator with Einstein Special Relativity time dilation. Calculates mission transit times across planetary and deep-space destinations, solves the Lorentz factor γ = 1/√(1 - v²/c²), and compares Earth observer coordinate time against astronaut proper ship time at relativistic speeds.
Key Capabilities & Features
- Comprehensive cosmic travel duration solver across kilometers, AU, light-years, and parsecs
- Special Relativity Lorentz factor (γ) and time dilation modeling for relativistic velocities
- Dual timeframe comparison: Earth Observer Time (Coordinate) vs Astronaut Ship Time (Proper)
- Preloaded destinations: Moon, Mars, Jupiter, Pluto, Proxima b, Sirius, Galactic Center, and Andromeda
- Propulsion presets from chemical Apollo rockets to fusion and 0.99c relativistic starships
How to Use Cosmic Travel Time & Relativistic Spaceflight Calculator
Pick Destination
Choose a celestial destination from the presets or enter a custom distance in light-years, AU, or km.
Select Flight Velocity
Enter velocity in km/s or as a fraction of the speed of light (e.g. 0.5c for 50% light speed).
Examine Time Dilation
Review elapsed Earth time versus elapsed spaceship time to observe relativistic time dilation effects.
Privacy & In-Browser Execution Guarantee
Spaceflight kinematic and relativistic models run entirely in your local browser.
Frequently Asked Questions
What happens to astronaut time at 99% the speed of light (0.99c)?
At 0.99c, the Lorentz factor γ is approximately 7.09. This means time for astronauts aboard the starship runs more than 7 times slower than on Earth. A journey to a star 7 light-years away takes ~7.07 years from Earth perspective, but only ~1.0 year for the travelers.