Resurs

The Resurs-O1-N4 satellite, made by the Russian space companies VNIIEM and SOVZOND, holds the boxes composing NINA. The satellite itself has been conceived to exploit the natural resources of the Earth: besides NINA, other instruments are placed on board for terrestrial observations. Some technical characteristics of the satellite are resumed in the Table 1. It is a medium-size class spacecraft, with a mass of 2500 kg (slightly more than 40 dedicated to NINA). Figure 1 The silicon detector (D1) is placed on the very top of the satellite, opposite to the Earth so to have a wide field of view not covered by other apparatus. The other modules are inserted instead in the central body of the spacecraft, connected to D1 by 7 meter long cables (Figure 1).
The connections and interfaces between Resurs and NINA are:

Mechanical: the detector is linked to the satellite by means of a L-shape structure, while the other boxes are fixed with bolts;
Electrical: NINA takes the tension, through the box P, from the power supply of the spacecraft, based on the solar panels;
Electronic (data transmission): data registered inside the detector are transmitted to the satellite and thereafter to ground, via telemetry;
Electronic (telecommands): the telecommands sent from ground are received and transferred to the NINA on-board computer, which processes them and consequently changes the detector working configuration.

Resurs4 NINA allowed mass is about 40 kg. The 32 modules of the telescope (silicon detectors plus read-out electronics) weight in total only 13 kg. The other parts (computer, power supply...) contribute to the remaining mass.

The maximum amount of data that can be sent to ground by the satellite is only 2 Mbyte/day. This severe constraint has imposed most of the decisions taken for NINA with respect to the electronics and the on-board computer.

 
Table 1
Technical characteristics of the satellite Resurs
Mass (with load) 2500 kg
Medium power supplied 500 W
Maximum power supplied 1200 W
Tension 27 V (24 - 34) V
Lifetime > 3 years