Traveling one light-year-the distance light travels in one year, about 5.88 trillion miles (9.46 trillion kilometers)-takes exactly one year if you could travel at the speed of light, which is about 186,000 miles (300,000 kilometers) per second
. However, no object with mass can currently travel at the speed of light due to physical laws, so actual travel times are much longer with existing technology. For example:
- NASA’s Parker Solar Probe, the fastest human-made object, travels at about 0.064% of the speed of light (430,000 mph), and it would take thousands of years to cover one light-year at that speed
- Voyager 1, the fastest outward-bound spacecraft so far, would take about 75,000 years to travel one light-year at its current speed
- A typical crewed spacecraft like Apollo, traveling around 39,400 km/h (24,500 mph), would take roughly 27,000 years to travel one light-year
- A plane flying at 965 km/h (600 mph) would take about 1 million years to cover the distance of a light-year
In summary, while light itself takes one year to travel a light-year by definition, current spacecraft would require thousands to tens of thousands of years or more to travel that distance
