GPM Flight Project

GPM Flight Project banner depicting (from left to right), GPM core being tested in the centrifuge, diagram of the GPM core, the GMI instrument being constructed in a lab, diagram of the GMI instrument, and the H-IIA rocket launching.


The GPM Core Observatory serves as a reference standard to a constellation of research and operational microwave sensors aimed at providing uniformly calibrated precipitation measurements around the globe every 2-4 hours for scientific research and societal applications. The GPM Flight Project was responsible for providing the following components:

  • GPM Core Observatory
  • GPM Microwave Imager (GMI) radiometer
  • Mission Operations Center for the Core Observatory
  • Ground Validation System
  • Precipitation Processing System (PPS) operations

The GPM Flight Project also works with internal and external NASA partners to coordinate other elements of the mission.




  • Diagram of the GPM Core Observatory shoing the GMI and DPR instruments
    Carrying both a dual frequency radar instrument and a passive microwave radiometer, the Core Spacecraft serves as a calibration standard for the other members of the GPM spacecraft constellation. The Core Spacecraft was developed and tested in-house at NASA Goddard Space Flight Center. The GPM Core Observatory's orbit inclination (65 degrees) is such that it enables the orbit to cut across the orbits of other microwave radiometers, sample the latitudes where nearly all precipitation occurs, and sample at different times of day. The GPM Core Observatory (GMI) instrument science data is...
  • GPM's DRP Instrument
    One of the prime instruments onboard the GPM Core Observatory is called the Dual-frequency Precipitation Radar (DPR). The DPR consists of a Ku-band precipitation radar (KuPR) and a Ka-band precipitation radar (KaPR). The KuPR (13.6 GHz) is an updated version of the highly successful unit flown on the TRMM mission. The KuPR and the KaPR are co-aligned on the GPM spacecraft bus such that that the 5 km footprint location on the earth is the same.
  • PMM Article Image
    The Global Precipitation Measurement (GPM) Microwave Imager (GMI) instrument is a multi-channel, conical- scanning, microwave radiometer serving an essential role in the near-global-coverage and frequent-revisit-time requirements of GPM. The instrumentation enables the Core spacecraft to serve as both a precipitation standard and as a radiometric standard for the other GPM constellation members. The GMI is characterized by thirteen microwave channels ranging in frequency from 10 GHz to 183 GHz. In addition to carrying channels similar to those on the Tropical Rainfall Measuring Mission (...

Latest Flight Project Images

The GPM Core Observatory successfully launched from Tanegashima Space Center, Japan, on February 27th, 2014 at 1:37pm EST - Learn More


4th GPM International GV Workshop
Helsinki, Finland , June 21-23, 2010 


  • The Tropical Rainfall Measuring Mission (TRMM) spacecraft re-entered the Earth’s atmosphere on June 15, 2015, at 11:55 p.m. EDT, over the South Indian Ocean, according to the U.S. Strategic Command’s Joint Functional Component Command for Space through...
  • The Precipitation Processing System (PPS) has begun producing updated GPM radiometer products as of 12/4/2014 due to an error discovered in the calculation of the Sun Angle in the PPS Geolocation Toolkit. This is considered a minor update with the...
  • The TRMM satellite is descending, and the users of TRMM Precipitation Radar (PR) data should be aware that the last production orbit of public PR data was orbit #96230 from October 7th, 2014. From that point forward, the TRMM PR data is suspended because...