Quick Facts
- Type: Instrument
- Launch Date: June 19, 1999
- Launch Location: Vandenberg Air Force Base, California
- Target: Earth
- Status: Past (Mission ended on November 23, 2009 due to an age-related mechanical failure.)
Overview
The SeaWinds instrument on the QuikSCAT satellite was a specialized microwave radar that measured near-surface wind speed and direction under all weather and cloud conditions over Earth's oceans.
The SeaWinds on QuikSCAT mission was a "quick recovery" mission to fill the gap created by the loss of data from the NASA Scatterometer (NSCAT) in 1997.
NASA's Quik Scatterometer (QuikSCAT) was lofted into space at 7:15 p.m. Pacific Daylight Time on Saturday (6/19/99) atop a U.S. Air Force Titan II launch vehicle from Space Launch Complex 4 West at California's Vandenberg Air Force Base. The satellite was launched in a south-southwesterly direction, soaring over the Pacific Ocean at sunset as it ascended into space to achieve an initial elliptical orbit with a maximum altitude of about 800 kilometers (500 miles) above Earth's surface. Please check out the Publications Section for frequent status reports and news.
SeaWinds uses a rotating dish antenna with two spot beams that sweep in a circular pattern. The antenna radiates microwave pulses at a frequency of 13.4 gigahertz across broad regions on Earth's surface. The instrument will collect data over ocean, land, and ice in a continuous, 1,800-kilometer-wide band, making approximately 400,000 measurements and covering 90% of Earth's surface in one day.
Science Objectives
- Acquire all-weather, high-resolution measurements of near-surface winds over global oceans.
- Determine atmospheric forcing, ocean response, and air-sea interaction mechanisms on various spatial and temporal scales.
- Combine wind data with measurements from scientific instruments in other disciplines to help us better understand the mechanisms of global climate change and weather patterns.
- Study both annual and semi-annual rain forest vegetation changes.
- Study daily/seasonal sea ice edge movement and Arctic/Antarctic ice pack changes.
Operational Objectives
- Improve weather forecasts near coastlines by using wind data in numerical weather- and wave-prediction models.
- Improve storm warning and monitoring.
Mission Description
- Launch Vehicle: Titan II
- Mission Life: 2 years (3 years consumables)
- Orbit: Sun-synchronous, 803 km, 98.6° inclination orbit
Spacecraft
- ADCS approach: 3-axis stabilized, Star Tracker/IRU/Reaction Wheels, C/A Code GPS
- Pointing Acc.: < 0.1° absolute per axis
- Pointing Knowl.: < 0.05° per axis
- Telecom: (Science) 2 Mbps S-band P/L
(Hskp) 5, 16, 256 Kbps S-Band, 2 Kbps S-Band uplink
- Propulsion: N2H4 Blowdown
- Mass: 970 Kg
- Orbital Avg Power: 874 W
- Data Capacity: 8 Gbits
Ground Systems
- Tracking by Earth Polar Ground stations Svalbard, Norway; Poker Flats, Alaska; Wallops Island, Virginia; and McMurdo, Antarctica; Hatoyama, Japan (contingency station).
- High-quality research data products produced at JPL and distributed to science community within 2 weeks of receipt.
- Scatterometer science data products are distributed through the JPL Physical Oceanography Distributed Active Archive Center (PO.DAAC), a scientific data distribution site: http://podaac.jpl.nasa.gov.
- Operational data products produced at National Oceanic & Atmospheric Administration (NOAA) for international meteorological community within 3 hours of data collection.
Instrument Description
- Radar: 13.4 gigahertz; 110-watt pulse at 189-hertz pulse repetition frequency (PRF)
- Antenna: 1-meter-diameter rotating dish that produces two spot beams, sweeping in a circular pattern
- Mass: 200 kilograms
- Power: 220 watts
- Average Data Rate: 40 kilobits per second
Measurements
- 1,800-kilometer swath during each orbit provides approximately 90-percent coverage of Earth's oceans every day.
- Wind-speed measurements of 3 to 20 meters/second, with an accuracy of 2 meters/second; direction, with an accuracy of 20 degrees.
- Wind vector resolution of 25 kilometers.
Mission Partners
- National Oceanic & Atmospheric Administration (NOAA)
- NASA Goddard Space Flight Center (GSFC)
- Ball Aerospace and Technologies Corporation
- U.S. Air Force Space and Missile Systems Center
- Honeywell Satellite Systems Operations
- Raytheon E-Systems Corporation
- Lockheed Martin Astronautics
- Hughes Electron Dynamics Division
The SeaWinds/QuikSCAT project is managed for NASA's Earth Science Enterprise by the Jet Propulsion Laboratory, a division of the California Institute of Technology.
