Ionospheric Observation
NanoSatellite Formation (ION-F)


--- Science mission


By Chucai Zhou


1. Introduction

     ION-F  is the satellite cluster system of  three 10-kg nanosatellites, designed by University of Washington (UW), Utah State University (USU) and Virginia Polytechnic Institute (VT), to investigate satellite coordination and management technologies and distributed ionospheric measurements. This system is scheduled to be launched in November 2001.

    The science objective is to understand the ionospheric density structures that can impose large amplitude and phase fluctuations on radio waves passing through the ionosphere. The constellation provides a unique opportunity to answer questions about ionospheric disturbances that can not be addressed by any other way. A single satellite can only provided very limited information on the dimensions and evolutionary time scales of the ionospheric disturbances it flies through because a full orbit (90 minutes) must occur between the next observation. In general the situation is even worse than this because only truly zero inclination equatorial satellites have a good possibility of measuring the same region twice due to the co-rotation of the ionosphere with the Earth.


2. Orbits and Tracking

What's known about ION_F:
With above orbital parameters, the  3D  and  2Dorbital trackings were simulated when following 'STATION' which indicates the Int'l Space Station  launching on 1998-11-20 at altitude 384 km and inclination 51.6 degree with orbital period 92 minutes
3. Instrumentations
    As a whole, there are Plasma Impedance Probe (PIP), DC Probe and GPS Scintillation mounting on the satellite system. PIPs, appearing on USU and UW's sat., measure the absolute plasma density locally. DC Probes, the electron saturation current probe, are deployed on all three units to measure the relative plasma density while GPS Scintillation, appearing only on VT's unit, extracts the time and position information for the whole system.
What's known:
4. Communication -- Downlink
    Two ground stations in USU in Logan, UT at long. 111º45', lat. 41°37' and VT in Blacksgurg, VA at long. 80º22' and lat. 37º07' are responsible to retrieve the measurement data from the whole system. The trigger signal of downlink will be sent from ground stations.