NEXTAR

NEXTAR (from NEC Next　Generation　Star) is a Low Earth orbit Earth observation satellite bus designed and manufactured by NEC Space Systems of Japan. This three axis stabilized platform has a bus dry mass of 250 kg, it can carry payloads up to 250 kg and 600 W. It uses tri-junction GaAs has an expected life between 3 and 5 years.

Its telemetry and control subsystem includes S band and X band channels.

Platform models
As of 2014, there are three different models of the NEXTAR standardized platform. All feature a common core of features like using the SpaceWire communications protocol, the SpaceCube2 on-board computer and autonomous control functions. The different models are:


 * NX-300L: Low Earth orbit platform for small observation satellites in the 300 to 500 kg range. It was born out of the ASNARO 1 work and is used mainly for Earth observation applications.
 * NX-1500L: Low Earth orbit platform for medium observation satellites in the 1000 to 1500 kg range. It began with the work on GCOM-W and is used mainly for Earth observation applications.
 * NX-G: Geosynchronous orbit platform for small communication satellites in the 1.5 to 3 tonne range. Based on the work of the WINDS satellite, it will be used mainly for communications applications.

List of satellites
Satellites using the NEXTAR platform.