The NPOESS Preparatory Project (NPP) mission is intended to bridge the gap between old and new systems by flying new instruments, on a new satellite bus, using a new ground data network. Originally planned for launch 5 years earlier as a joint NASA/NOAA/DOD project, NPP was to be a pathfinder mission for the larger National Polar-orbiting Operational Environmental Satellite System until DOD participation in the larger project was dissolved. The project continued forward in its civilian weather forecasting replacing the NOAA Polar Operational Environmental Satellites

Polar Operational Environmental Satellites

The Polar Operational Environmental Satellite project operates a constellation of weather satellites in polar orbits around the Earth. It is a joint effort between the National Oceanic and Atmospheric Administration and the European Organisation for the Exploitation of Meteorological Satellites...

 (POES) series and ensuring the continuty of climate measurements begun by NASA's Earth Observing System

Earth Observing System

The Earth Observing System is a program of NASA comprising a series of artificial satellite missions and scientific instruments in Earth orbit designed for long-term global observations of the land surface, biosphere, atmosphere, and oceans of the Earth. The satellite component of the program was...

.

The five instruments include the Advanced Technology Microwave Sounder (ATMS), the Cross-track Infrared Sounder (CrIS), the Clouds and the Earth's Radiant Energy System

Clouds and the Earth's Radiant Energy System

Clouds and the Earth's Radiant Energy System is NASA climatological experiment from Earth orbit.The CERES are scientific satellite instruments, part of the NASA's Earth Observing System...

 (CERES), the Visible Infrared Imager Radiometer Suite (VIIRS) and the Ozone Mapping and Profiler Suite (OMPS). The NPP project encountered various troubles and was reviewed.

The spacecraft was launched 28 October 2011 from Vandenberg Air Force Base

Vandenberg Air Force Base

Vandenberg Air Force Base is a United States Air Force Base, located approximately northwest of Lompoc, California. It is under the jurisdiction of the 30th Space Wing, Air Force Space Command ....

 via a Delta II

Delta II

Delta II was an American space launch system, originally designed and built by McDonnell Douglas. Delta II is part of the Delta rocket family and was in service from 1989 until November 1, 2011...

 in the 7920-10 configuration ( Extra Extended Long Tank with RS-27A engine first stage, 9 GEM-40

Graphite-Epoxy Motor

A Graphite-Epoxy Motor is a high-performance, solid rocket motor, used for supplemental thrust on several launch vehicles, including the Boeing Delta II and Delta IV. They are designed to allow launch vehicles to deliver larger payloads to orbit...

 solid rocket motors, type 2 second stage with Aerojet

Aerojet

Aerojet is an American rocket and missile propulsion manufacturer based primarily in Rancho Cordova, California with divisions in Redmond, Washington, Orange, Gainesville and Camden, Arkansas. Aerojet is owned by GenCorp. They are the only US propulsion company that provides both solid rocket...

AJ10 engine, no 3rd stage and a 10 meter faring).

The VIIRS sensor onboard the spacecraft acquired its first measurements on November 21, 2011.

External links

• mission page (NASA)
• press kit (NASA)
• press kit (Ball Aerospace)
• Brochure (NASA)