By David Szondy
|The NASA missions will use CubeSats similar to Montana State University's Explorer-1 [Prime] CubeSat (Image: Montana State University, Space Science and Engineering Laboratory)|
Having landed the car-sized Curiosity rover on Mars, NASA is looking in the other direction with its Small Spacecraft Technology Program. Dedicated to improving small satellite technology, the program recently awarded contracts to three teams working in the areas of communications, formation flying and docking. The tricky bit is that the satellites they’re working with are only four inches (10.16 cm) tall.
The three projects are based on CubeSats, a class of cubical nanosatellites that are four inches (10.16 cm) on each side and weigh about three pounds (1.36 kg). This may seem rather small for a satellite – and it is – but these tiny spacecraft do have many advantages over their larger counterparts. First, they are very inexpensive as satellites go. Second, being so small and light, they can be sent into orbit as hitchhikers with bigger satellites for a fraction of the cost.
But what really sets the CubeSats apart is that what they lack in complexity, they make up for in numbers. CubeSats aren’t so much independent spacecraft as they are building blocks. Instead of going up singly, groups of CubeSats can be launched that can either fly in formation or they can dock with one another to form a larger satellite with greater capabilities. Think of them as like those electronic modular toys where you plug modules together to make radios or other devices.
The three missions selected by NASA are intended to exploit the advantages of the CubeSat standard. One, called the "Integrated Solar Array and Reflectarray Antenna (ISARA) for High Bandwidth CubeSat," is a US$5.5 million mission by Richard Hodges, NASA Jet Propulsion Laboratory, Pasadena, California and Pumpkin Inc. of San Francisco. Its purpose is to increase the amount of data that a tiny satellite can transmit by turning its solar array into a reflector for the satellite’s communications antenna.
Another $3.6 million project by Siegfried Janson, Aerospace Corporation of El Segundo, California, is for "Integrated Optical Communications and Proximity Sensors for Cubesats." This involves a pair of CubeSats that will use lasers for communicating with the ground as well as radar and optical sensors to help nanosatellites when maneuvering near one another.
The third is the "Proximity Operations Nano-Satellite Flight Demonstration," by Charles MacGillivray, Tyvak Nano-Satellite Systems LLC of Orange, California, Applied Defense Solutions Inc. of Columbia, Maryland, 406 Aerospace LLC of Bozeman, Montana, and California Polytechnic State University of San Luis Obispo. This $13.5 million mission will use two satellites, each made of three CubeSats, to practice rendezvous and docking maneuvers in orbit.
The flights are due to take place in 2014 and 2015.