Use of CubeSats for High-Density Global Coverage

Studies indicate that the value of Radio Occultation soundings increase in a linear fashion up to at least 120,000 soundings per day (see figure). The use of small 3U cubesats make such soundings economical. Spire is committed to development of a cubesat constellation that can take large numbers of Radio Occultations each day. One issue in development of the constellation is to distribute the soundings over the globe in accordance with their potential impact. One approach is to aim for approximately equal coverage by area. Another important issue is the latency between the observation and its availability to numerical weather prediction and other users. Ideally, the observations should be available within about 30 minutes for use in some applications. The availability of commercial data to governements charged with public safety is another consideration. The weather community has a history of international data sharing, but this must be combined with the need for a commercial company to be compensated for its services. The potential of large constellations of inexpensive satellites delivering very valuable observations can be very positive for the global weather and climate enterprise.