Cyclone Global Navigation Satellite System
| Mission type | Weather research |
|---|---|
| Operator | University of Michigan / Southwest Research Institute |
| Website | http://cygnss-michigan.org/ |
| Spacecraft properties | |
| Launch mass | 27.5 kg per satellite |
| Dimensions | Deployed: 159 cm x 51 cm |
| Power | 34.7 Watts |
| Start of mission | |
| Launch date | December 12, 2016 |
| Rocket | Pegasus XL |
| Launch site | Cape Canaveral Air Force Station |
| Orbital parameters | |
| Inclination | 35 degrees |
The Cyclone Global Navigation Satellite System (CYGNSS) is a system being developed by the University of Michigan and Southwest Research Institute with the aim of improving hurricane forecasting by better understanding the interactions between the sea and the air near the core of a storm. In June 2012 NASA sponsored the project for $152 million with the University of Michigan leading its development.[1] [2] Other participants in CYGNSS' development include the Southwest Research Institute and Surrey Satellite Technology[3] The plan is to build a constellation of eight micro-satellites that are launched into low Earth orbit.[2] [4] The program plans to launch December 12, 2016 and then observe two hurricane seasons.[5] [6] NASA plans to carry the satellites in a single launch vehicle.[7] CYGNSS is the first of NASA's Earth Venture-class spaceborne missions (a part of the NASA Pathfinder program);[3] the previous EV selections were divided among five airborne remote sensing missions. Launch is scheduled for November 2016[8] for a two-year run.[9]
Background
Forecasting the tracks of tropical cyclones since 1990 has improved by approximately 50%; however, in the same time period there has not been a corresponding improvement in forecasting the intensity of these storms. A better understanding of the inner core of tropical storms could lead to better forecasts; however, current sensors are unable to gather a sufficient quality of data on the inner core due to obscuration from rain bands surrounding it and to infrequent sampling. In order to improve the models used in intensity forecasts, better data are required.[10][11]
In order to overcome these limitation, CYGNSS will measure the ocean surface wind field using a bi-static scatterometry technique based on GPS signals.[10][11] Each satellite receives both direct GPS signals and signals reflected from the Earth's surface; the direct signals pinpoint spacecraft position a provide a timing reference, while the reflected or "scattered" signals provide information about the condition of the sea's surface. Sea surface roughness corresponds to wind speed.[12] Using a constellation of eight small satellites in place of a smaller number of larger satellites enables more frequent observations: the mean revisit time is predicted to be 7 hours.[10][11]
Instruments
Each CYGNSS satellite carries a Delay Doppler Mapping Instrument (DDMI), consisting of:
- a Delay Mapping Receiver (DMR)
- two nadir-pointing antennas
- one zenith-pointing antenna
The instrument receives GPS signals for the purposes of bi-static scatterometry.[12]
References
- ^ "U-M To Lead $152M NASA Satellite Project". Associated Press. June 19, 2012. Retrieved June 22, 2012.
{{cite news}}: Cite has empty unknown parameter:|coauthors=(help) - ^ a b Clark, Stephen (June 21, 2012). "NASA funds satellite mission to measure hurricane winds". SpaceflightNow. Retrieved June 22, 2012.
- ^ a b "NASA Selects Low Cost, High Science Earth Venture Space System". NASA. June 18, 2012. Retrieved June 24, 2012.
- ^ Aldridge, James (June 21, 2012). "NASA taps SwRI on research effort to map hurricanes". San Antonio Business Journal. Retrieved June 22, 2012.
{{cite news}}: Cite has empty unknown parameter:|coauthors=(help) - ^ "CYGNSS Mission". University of Michigan. Retrieved 2016-02-11.
- ^ Kozlowski, Kim (June 22, 2012). "University of Michigan, NASA team up for hurricane satellite project". The Detroit News. Retrieved June 22, 2012.
{{cite news}}: Cite has empty unknown parameter:|coauthors=(help) - ^ "U-M to Lead $150M NASA Hurricane Prediction Project". Atmospheric, Oceanic and Space Sciences. Retrieved June 22, 2012.
{{cite web}}: Cite has empty unknown parameter:|coauthors=(help) - ^ "Missions - CYGNSS". NASA. 2013-04-30. Retrieved 2013-09-08.
- ^ Leone, Dan (June 19, 2012). "NASA To Fund Wind-monitoring Smallsat Constellation". Space News. Retrieved June 22, 2012.
{{cite news}}: Cite has empty unknown parameter:|coauthors=(help) - ^ a b c "CYGNSS." University of Michigan. Retrieved: 15 August 2015
- ^ a b c Ruf, Christopher S.; Atlas, Robert; Chang, Paul S.; Clarizia, Maria Paola; Garrison, James L.; Gleason, Scott; Katzberg, Stephen J.; Jelenak, Zorana; Johnson, Joel T. (2015-06-26). "New Ocean Winds Satellite Mission to Probe Hurricanes and Tropical Convection". Bulletin of the American Meteorological Society. 97 (3): 385–395. doi:10.1175/BAMS-D-14-00218.1. ISSN 0003-0007.
- ^ a b "CYGNSS Factsheet October 2014". University of Michigan. Retrieved: 27 September 2015.