National Polar-orbiting Operation Environmental Satellite System.

The NPP Project is a joint effort of the National Polar-orbiting Operational 

Environmental satellite system (NPOESS) Integrated Program Office (IPO), the National 

Oceanic and Atmospheric Administration (NOAA) and NASA. 

The NPP spacecraft will be an Earth observing satellite carrying four instruments into a 

polar, sun-synchronous, 824 km orbit. NPP will be launched on a Delta II launch vehicle. 

The design lifetime of the NPP spacecraft is 5 years. 

Instruments 

The following instruments will be a part of the NP spacecraft: 

• The Visible-Infrared Imager Radiometer Suite (VIIRS) instrument is a 

multispectral scanning radiometer with 3000 km swath width and derives its 

heritage from Advanced Very High Resolution Radiometer (AVHRR), Optical 

Line Scanner (OLS), Moderate Resolution Imaging Spectroradiomenter 

(MODIS), and Sea-viewing Wide Field-of-View Sensor (SeaWIFS). 

• The Cross Track Infrared Sounder (CrIS) instrument is a Michelson 

interferometer. Its heritage is the High Resolution Infrared Sounder (HIRS), 

Atmospheric Infrared Sounder (AIRS), and the Infrared Atmospheric Sounding 

Interferometer (IASI) radiometer. It is co-registered with the Advanced 

Technology Microwave Sounder (ATMS) and is designed to work in conjunction 

with it. 

• The ATMS instrument is a passive microwave radiometer with a swath width of 

2300 km. Its heritage is the Advanced Microwave Sounding Unit (AMSU) A1/A2 

and the Humidity Sounder for Brazil (HSB). 

• The Ozone Mapping and Profiler Suite (OMPS) measures solar scattered radiation 

to map the vertical and horizontal distribution of ozone in the Earth’s atmosphere 

using a nadir ultra-violet (UV) sensor and limb-scanning UV/visible (VIS) 

sensors. Its heritage is the Solar Backscatter Ultraviolet  (SBUV)/2 radiometer, 

the Total ozone Mapping Spectrometer (TOMS), the Shuttle ozone Limb Scatter 

Experiment (SOLSE) and the Limb Ozone Retrieval Experiment (LORE).

The NPP Mission Success is determined by its capabilities to provide continuation of a 

group of earth system observations initiated by the Earth Observing System (EOS) Terra, 

Aqua and Aura missions. The NPP Mission Success is also judged by its ability to reduce 

the risks associated with its advance observational capabilities as they are being 

transitioned from the NASA research program into the NPOESS operational program in 

support of both the Department of Defense (DoD) and NOAA. These include pre- 

operational risk reduction demonstration and validation for selected NPOESS 

instruments, and algorithms, as well as ground data processing, archive and distribution. 

Together these data records will fulfill the U.S. Climate Change Research Program 

(CCRP) objectives of understanding the earth’s climate system and its variability on a 

decadal basis. 

The specific NASA science criteria are: 

1. Continue vertical temperature and moisture profiles of the Earth’s atmosphere 

with accuracy, extent, and frequency consistent with those made with the Aqua 

satellite sensors. 

2. Continue a record of sea surface temperature with accuracy, extent and frequency 

consistent with those made with Terra and Aqua sensors. 

3. Continue a record of surface biophysical and climatic parameters with accuracy, 

extent and frequency consistent with those made with Terra and Aqua sensors. 

4. Continue a record of cloud and aerosol properties with accuracy, extent, and 

frequency consistent with those made with Terra and Aqua sensors. 

5. Continue a record of ozone total column abundance and vertical profile with 

accuracy, extent, and frequency consistent with those made with previous US 

spacecraft making comparable measurements.