admin SAN FRANCISCO— After a successful rocket launch from India, the beginnings of a new satellite constellation for Earth observation took place. An existing flotilla of more than 80 microsatellites owned by the startup Spire Global, based here, captures signals that have traversed the atmosphere from GPS satellites to measure key properties such as temperature and humidity. Now from the same company two new microsatellites will collect GPS signals after they bounce off land or ocean to analysis conditions at the surface.
The long wavelengths of GPS can peer through clouds and heavy rain to measure the winds of hurricanes and other storms, unlike the microwaves used by traditional weather satellites. The reflected signal can also make known sea ice cover and soil moisture indicating drought and guide storm forecasts. Spire’s director of Earth observations Dallas Masters said, “We’re trying to produce data that will be used for the long term,” alomg with announment of the launch this week at a meeting of the American Geophysical Union.
A constellation of eight NASA microsatellites which is called the Cyclone Global Navigation Satellite System (CYGNSS) over the past few years has proved that harvesting GPS reflections can work from space, providing measures of hurricane wind speed that could measurably improve hurricane forecasts.
The National Oceanic and Atmospheric Administration (NOAA) explored the possibility of adopting CYGNSS data for its forecasts as no operational satellites now supply soil moisture measurements for weather forecasting. The agency’s technical requirements were an obstacle, opined by Chris Ruf, CYGNSS’s principal investigator and an atmospheric scientist at the University of Michigan in Ann Arbor.
Joined with ride as a secondary payload on an Indian rocket carrying a radar-imaging satellite The new Spire microsatellites resemble small 5-kilogram monoliths. A second version of the reflection satellite into polar orbit will be launched by Spire next year, and it hopes to eventually send more than three dozen into orbit. Spire is one of a handful of companies seeking to carve out a niche in providing satellite data to private users, government agencies, and scientists, with an eye especially on improving weather forecasts. Both NASA and NOAA are now studying data from the company’s existing satellites as part of pilot projects; Masters hopes the next phase of the NOAA pilot will expand to include GPS reflection data.
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