The term ‘Small is beautiful’, coined by the British economist E. F. Schumacher, is a call to empower people through simple but appropriate technologies. The term seems to have been given a new twist with the advent of small satellites which, when operated in a cluster or constellation, can mimic bigger satellites.
Small satellites draw upon two major technological advances. One is the miniaturization of electronics and the other is autonomous control which turns the satellite into a ‘smart’ satellite. Such satellites can fly ‘in formation’ required for a given task. For example, a region requiring rapid repeat coverage could have a number of similar satellites overfly the region at intervals of say a few hours. If the task is to cover a large swath, the satellites could then form an array across the flight direction. Autonomous control becomes easier because small satellites have small mass and therefore require low energy control systems.
Will small satellites spell the death knell for big complex satellites? Not quite. Big satellites will still be around for bigger tasks like centimeter-level precision imaging. They will also be needed for non-imaging sensors like scatterometers and for radar sensors like synthetic aperture imaging radars. Small satellites may present a potential headache in terms of orbit management as hundreds of them begin to orbit the earth. Being small they are also more vulnerable to space debris. Data policy in terms of access, reuse and archiving will also need to be revisited. Another potential area of conflict could be standards for imaging, formatting data and dissemination.
However, for the consumers, small satellites present a whole new world. Paucity of data will be a thing of the past. In fact, there will be better opportunities for deciding revisit rates, monitoring changes and tracking activity. Data overload may require curating of the data for specific purposes. This will open up a market for value addition where customers can outsource analytics support and buy specific information rather than basic remote sensing data sets. In short, small satellites could result in a totally new approach to remote sensing.