Using current spacecraft, approximately how long would it take to reach the nearest stars?

• A. Hundreds of thousands of years
• B. A few decades
• C. Several million years
• D. A few months

Answer: (A)

Interstellar travel times with current technology come down to distance divided by speed. The nearest star is about 4.3 light-years away. Our fastest spacecraft, like Voyager 1, travels around 17 kilometers per second, which is about 0.00006 times the speed of light. Division gives a travel time of roughly 4.3 ly / 0.00006 c ≈ 70,000 years. So the journey is on the order of tens of thousands to a hundred thousand years. Among broad, coarse categories, that fits the idea of hundreds of thousands of years, which is why this option is the best match. The other choices describe timescales that are far too short or far too long given the actual distances and speeds involved.