Physics of the Future: How Science Will Shape Human Destiny and Our Daily Lives by the Year 2100

The exploration of the solar system will be made more effective through the construction of small but powerful nano-scale devices that will be easy to transport and deliver to the surface, below the surface, and into the atmospheres of our neighboring planets and satellites. … One can even extrapolate these possibilities to interstellar exploration.”
    In nature, mammals produce just a few offspring and make sure that all survive. Insects produce large quantities of offspring, only a tiny fraction of which survive. Both strategies can keep the species alive for millions of years. Likewise, instead of sending a single, expensive starship to the stars, one can send millions of tiny starships, each costing a penny and requiring very little rocket fuel.
    This concept is patterned after a very successful strategy found in nature: swarming. Birds, bees, and other flying animals fly in flocks or swarms. Not only is there safety in numbers but the swarm also acts as an early warning system. If a dangerous disturbance happens in one part of the swarm, such as an attack by a predator, the message is quickly relayed to the rest of the swarm. They are also quite efficient in energy. When birds fly in a characteristic V pattern, the wake and turbulence created by this formation reduce the energy necessary for each bird to fly.
    Scientists characterize a swarm as a “superorganism,” one that appears to have an intelligence of its own, independent of the abilities of any singleindividual. Ants, for example, have a very simple nervous system and a tiny brain, but together they can create complex anthills. Scientists hope to incorporate some of these lessons from nature by designing swarm-bots that might one day journey to other planets and stars.
    This is similar to the hypothetical concept of smart dust being pursued by the Pentagon: billions of particles sent into the air, each one with tiny sensors to do reconnaissance. Each sensor is not very intelligent, but collectively they can relay back mountains of information. The Pentagon’s DARPA has funded this research for possible military applications, such as monitoring enemy positions on the battlefield. In 2007 and 2009, the Air Force released position papers detailing plans for the coming decades, outlining everything from advanced versions of the Predator (which today cost $4.5 million apiece) to swarms of tiny sensors smaller than a moth costing pennies.
    Scientists are also interested in this concept. They might want to spray smart dust to instantly monitor thousands of locations during hurricanes, thunderstorms, volcanic eruptions, earthquakes, floods, forest fires, and other natural phenomena. In the movie
Twister,
for example, we see a band of hardy storm chasers risking life and limb to place sensors around a tornado. This is not very efficient. Instead of having a handful of scientists placing a few sensors during a volcanic eruption or tornado to measure temperature, humidity, and wind velocity, smart dust can give you data from thousands of different positions at once over hundreds of miles. When fed into a computer, this data can instantly give you real-time information about the evolution of a hurricane or volcano in three dimensions. Commercial ventures have already been set up to market these tiny sensors, some no larger than the head of a pin.
    Another advantage of nanoships is that they require very little fuel to send them into space. Instead of using huge booster rockets that can reach only 25,000 miles per hour, it is relatively easy to send tiny objects into space at incredible velocities. In fact, it is easy to send subatomic particles near the speed of light using ordinary electric fields. These nanoparticles carry a small electric charge and can be easily accelerated by electric fields.
    Instead of using enormous resources to send a probe to another moon or planet, a single probe might have the ability to self-replicate, and thus create an entire factory or even moon base. These self-replicating probescan then blast off to explore other worlds. (The problem is to create the first self-replicating nanoprobe, which is still in the distant future.)
    In 1980, NASA took the idea of self-replicating robot probes seriously enough to convene a special study, called Advanced Automation for Space Missions, which was conducted at the University of Santa Clara and looked into several possibilities. One explored by NASA scientists was to send small,