A groundbreaking proposal suggests sending minuscule, paperclip-sized spacecraft, propelled by powerful lasers, on an ambitious journey to a nearby black hole to rigorously test Albert Einstein's theory of general relativity in extreme conditions. The concept, put forth by astrophysicist Cosimo Bambi, involves launching these "nanocrafts," equipped with advanced sensors and light sails. Ground-based lasers would accelerate these probes to speeds approaching one-third of the speed of light.
At such velocities, a nanocraft could reach a black hole situated 20 to 25 light-years away within approximately 60 to 75 years. The data collected would then take an additional 20 to 25 years to transmit back to Earth, making the total mission duration close to a century. While the closest known black hole, Gaia BH1, is over 1,500 light-years away, models suggest that undetected black holes might exist much closer, potentially within 20 to 25 light-years. Bambi estimates that the cost of the necessary laser array, which today would be around one trillion euros, could decrease to approximately one billion euros within 30 years, making it comparable to current flagship space missions. This visionary proposal represents a bold step towards probing the fundamental nature of black holes and spacetime, pushing the boundaries of our understanding of the universe. The development of laser propulsion, as seen in projects like Breakthrough Starshot aiming for speeds of 20% the speed of light to reach Alpha Centauri, is a key enabler for such ambitious interstellar journeys.