HD 219134 is an orange dwarf 21 light-years away in the constellation Cassiopeia. It's the closest star with a transiting exoplanet that can be seen without a telescope.
HD 219134 is 21.25 light-years from Earth. That is about 201 trillion km (125 trillion miles), or 1.34 million astronomical units.
| Unit | Distance |
|---|---|
| Light-years | 21.25 |
| Kilometers | 201,000,000,000,000 km |
| Miles | 125,000,000,000,000 miles |
| Astronomical units (AU) | 1,340,000 astronomical units |
| Parsecs | 6.52 |
Light from HD 219134 takes 21.25 years to reach Earth, so the light you see tonight left HD 219134 21.25 years ago.
Voyager 1, the fastest object humans have sent into deep space, travels at about 17 km/s. It would need about 374,700 years to cover this distance.
Notable For: Brightest star visible to naked eye with transiting exoplanet
At light speed, it would take 21 years to reach HD 219134. At 1g constant acceleration with deceleration, a traveler would experience about 10.6 years.
Yes, HD 219134 is visible to the naked eye at magnitude 5.5, making it the brightest star with a transiting exoplanet that you can observe without a telescope.
HD 219134 is 21.25 light-years from Earth, which is about 201 trillion km or 125 trillion miles. Light from HD 219134 takes 21.25 years to reach us.
HD 219134 is 21.25 light-years from Earth. One light-year is about 9.46 trillion km, the distance light travels in one year. In parsecs, HD 219134 is about 6.52 parsecs away.
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.
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.
The Time Dilation Formula is:
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)