To reach the vicinity of the nearest star, 24 trillion miles away, in less than 20 years, an interstellar space probe would have to travel at a substantial fraction of the speed of light. Newton's laws of motion, published 300 years ago, predict that the greater the mass of an object the greater is the force required to increase it's velocity. In order to alleviate the need for the virtually unaffordable amount of energy required to accelerate a normal sized spacecraft to a speed of 20% of the speed of light, the Breakthrough Starshot program has funded the creation of 'Sprite' , the world's smallest spacecraft. About the size of a saltine cracker and having a mass of less than 2 dimes, the single-board Sprite spacecraft has all the essentials; solar panels, computing electronics, thermometers, gyroscopes, radio communication equipment and more. Working prototypes have been launched into Earth orbit by the Indian Space Research Organization attached to the Italian Max Valier and Latvian Ventra satellites. One of them has sent back signals which have been received by Cornell University's ground station. Dr. Zac Manchester who started the Sprite Spacecraft program while earning a PhD at Cornell University envisions using tiny spacecraft to explore near Earth Space as well as asteroids and moons in our solar system. In the future, fleets of the decedents of Sprite could be sent to explore intriguing planets in nearby alien solar systems. These tiny explorers will be propelled by high power Earth bound lasers directed at their solar sails and could reach and explore distant planets in a reasonable amount of time.
