National Environmental Satellite, Data and Information Service (NESDIS)



COSMIC-2 satellite
CREDIT: COSMIC-2 satellite (Image credit: Surrey Satellite Technology Ltd.)

What is COSMIC-2?

To make accurate weather forecasts, meteorologists need a continuous source of data about our atmosphere. The Constellation Observing System for Meteorology, Ionosphere, and Climate-2 (COSMIC-2) is a network of six remote-sensing microsatellites. Building upon the success of the COSMIC-1 program, COSMIC-2 will constantly orbit Earth collecting atmospheric data used for weather forecasting, climate monitoring, and space weather research.

NOAA is partnering with the U.S. Air Force (USAF), Taiwan’s National Space Organization (NSPO), and the University Corporation for Atmospheric Research (UCAR) on this satellite program.

How does COSMIC-2 work?

COSMIC Radio Occultation


This team of COSMIC satellites circles the equator at approximately 17,000 miles per hour and uses a technique called radio occultation to collect information on our planet’s atmosphere. Here’s how it works: Global Positioning System (GPS) satellites constantly send signals down to receivers on Earth, but those signals get distorted along the way because the density of Earth’s atmosphere changes with height. COSMIC-2 satellites can detect and measure any small bends in those signals before they are cut off by Earth’s horizon. The three-minute period before the radio signal is cut off is known as radio occultation, and that data are what gives scientists near real-time information about the Earth’s atmosphere including conditions such as: temperature, pressure, density and water vapor.