Interstellar Possibilities

Reaching other star systems is the ultimate challenge. The nearest star, Proxima Centauri, lies 4.24 light-years away. The fastest spacecraft ever launched, the Parker Solar Probe, hits a peak speed near 692,000 km/h. Even at that pace, the journey would take roughly 6,600 years. Practical interstellar travel will require radically new propulsion.

The Breakthrough Starshot initiative proposes using powerful ground-based lasers to accelerate gram-scale probes to 20% the speed of light, reaching Proxima Centauri in about 20 years. The first interstellar mission will likely be a tiny probe.