Sirius, the Dog Star, is the brightest star in Earth's night sky at magnitude -1.46. Located 8.6 light-years away in Canis Major, it's actually a binary system with a white dwarf companion. Calculate your travel time with relativistic effects.
Distance8.6 light-years
Star TypeBinary system (A1V + DA2)
ConstellationCanis Major
Apparent Magnitude-1.46
Time Dilation Formula Calculator
Journey Summary
Traveler's Time:
N/A years
Time experienced on the spacecraft
Observer's Time:
N/A years
Time passed on Earth
Maximum Velocity:
N/A c
Peak speed (as fraction of light speed)
Energy Required:
N/A J
Total energy needed for the journey
Speed vs Time
This chart shows how quickly you accelerate to a fraction of the speed of light over time.
Distance vs Time
Shows distance covered (in light-years) over time.
Traveler's vs Observer's Time
Shows how time experienced by the traveler differs from time on Earth.
Energy Requirement vs Distance
Shows the (simplified) energy requirements for maintaining relativistic travel as distance increases.
Doppler Shift vs Time
Shows how the Doppler effect changes observed wavelengths over time.
Velocity vs Distance
Shows how your speed changes as you travel further from your starting point.
Lorentz Factor vs Time
Shows how the Lorentz factor (γ) grows over time as relativistic effects increase.
Proper vs Observer Distance
Shows how distance measurements differ between the traveler's frame and the observer's frame.
Facts About Sirius
At light speed, the journey would take 8.6 years
Sirius is about twice as massive as the Sun and 25 times more luminous
Ancient Egyptians based their calendar on Sirius's heliacal rising
Notable For: Brightest star in Earth's night sky
Frequently Asked Questions
How long would it take to travel to Sirius at light speed?
At the speed of light, it would take 8.6 years to reach Sirius from Earth. At 99% light speed, a traveler would experience only about 1.2 years due to time dilation.
Why is Sirius the brightest star?
Sirius is the brightest star in our night sky because it's both relatively close (8.6 light-years) and intrinsically luminous (25 times brighter than the Sun). It's not the most luminous star in the galaxy, just the brightest from our perspective.
This time dilation calculator lets you enter a distance in light-years and acceleration in m/s² to see how time dilation affects your journey. It shows differences between traveler and observer times, maximum velocity, energy requirements, Doppler shift, Lorentz factor, and how distances vary between reference frames. Charts appear after you calculate.
Results
Traveler's Time: How much time the person on the spaceship experiences
Observer's Time: How much time passes on Earth during the journey
Maximum Velocity: The highest speed reached, as a fraction of light speed
Interactive Charts
Speed vs Time: How quickly you accelerate towards light speed
Distance vs Time: How far you've traveled over time
Traveler's vs Observer's Time: Compare time passage between Earth and spaceship
Energy Requirement vs Distance: How much energy is needed as you travel further
Doppler Shift vs Time: How light wavelengths change during your journey
Velocity vs Distance: Your speed at different distances
Lorentz Factor vs Time: How much time dilation increases with speed
Proper vs Observer Distance: How distance measurements differ between frames
What is Time Dilation?
Time dilation is an effect from Einstein's theory of special relativity. The faster you move, the slower time passes for you compared to someone standing still. At 90% of light speed, time passes about 2.3 times slower for the traveler than for someone on Earth.
What is the Time Dilation Formula?
The Time Dilation Formula is:
t' = t / √(1 - v²/c²)
Where:
t' = time measured by the observer (on Earth)
t = time experienced by the traveler
v = velocity of the traveler
c = speed of light (299,792,458 meters per second)