Some of the first spacecraft that humanity sends to other solar systems may carry microscopic ambassadors from Earth. The $100 million Breakthrough Starshot initiative is working to develop the technology required to accelerate tiny, sail-equipped probes to 20 percent the speed of light, using powerful lasers. If everything goes well, large fleets of these 1-gram spacecraft could begin launching toward Proxima b and other nearby alien worlds within 20 years or so, project representatives have said. The probes would characterize these planets in detail and search for signs of life, but some could perform other work as well. The project offers a great opportunity to investigate the feasibility of interstellar panspermia.
The panspermia hypothesis posits that Earth life might have arrived, rather than originated, here. This idea is not as fringe as you may think. For example, some scientists argue that, in the ancient past, the Martian environment was more conducive to life's emergence than that of Earth. And it's not terribly uncommon for the two planets to exchange material, in the form of rocks and dirt blasted into space by asteroid strikes. Orbital dynamics dictates that it's much easier for Martian stuff to reach Earth than the other way around, so we may all be Martians, according to this line of thinking. It may even be possible for life-forms to move from one star system to another, some panspermia adherents say.
Intelligent aliens could set panspermia in motion, either unintentionally (via contaminated spacecraft) or intentionally (in an effort to seed other worlds). Breakthrough Starshot, and projects like it, could give humanity this ability as well.
Kemo D. 7