What is the approximate speed of Voyager 1 relative to the Sun? It is about 17 km/s. This is Voyager 1’s heliocentric speed as it recedes from the Sun, equivalent to roughly 61,000 km/h or 38,000 mph.
That speed is the result of the spacecraft’s launch energy and its gravitational-assist flybys. Voyager 1 flew past Jupiter in March 1979 and Saturn in November 1980; Jupiter’s gravity substantially increased its solar-system escape speed, while Saturn redirected the spacecraft onto its present trajectory.
The figure is a velocity relative to the Sun, not the spacecraft’s speed relative to Earth or to the surrounding interstellar medium. It is also an approximate value: the exact heliocentric velocity varies slightly with reference frame and orbital calculations. The commonly cited value is about 17.0 km/s.
Voyager 1 is the fastest spacecraft in terms of heliocentric recession speed. At that pace, it covers approximately 325 million miles per year, yet crossing even one light-year would still take about 18,000 years.