Exective summary

The Science of SCOPE

The SCOPE mission strategy

SCOPE in the Roadmap

SCOPE and the simulation studies

Link to Cross-Scale (ESA)

Data handling scheme

How to handle huge data?

The SCOPE will onboard high capability instruments which generate science data with high data rate. e.g. SCOPE mother S/C ~13Mbps. However, comparing with the data production rate, telemetry data rate is much lower because of the limited resource both on the ground and the onboard facilities, for example, SCOPE mother S/C can be implemented 4~8 Mbps bandwidth at most. Therefore, we have to select scientifically worthy dataset with an efficient way and to reduce amount of data set that are transferred to the ground.

Basically, 3 concepts for the data reduction are considered.
1) “Burst Mode” is operated during pre-programmed periods.
In this case, selected data periods sometimes does not have enough accuracy.
2) “Burst Mode” is triggered by some signals from science instruments.
THEMIS’ experience is quite helpful. (MMS will also be) for the onboard triggering method. However, we are afraid that unexpected phenomena are lost.
3) Human efforts of data selection based on survey data.
Large capacity of data recorder is strongly required, but exact selection for scientists is available.

Procedure of Data Acquisition

In order to appropriately select scientific events with the highest time resolution data set (=Burst Data (BD)), SCOPE S/Cs store “onboard selected” BD of all the science instrument on the data recorder as possible. They are candidates for the dump to the ground. Lower bit rate Summary Data (SD) set for continuous observations are also processed, and they have to be dumped to the ground. The roles of SD are 1) Quick Look for BD selection, 2) Understand the context of the selected BD event, and 3) Data analysis for larger and longer scale phenomena (electron dynamics is not so important).

All the far-daughter S/Cs make direct downlink connection, and the data handling operation of the far-daughter S/Cs is the same as the mother S/C.

Planning of BD downlink

The mother S/C and all the far-daughter S/Cs stores all the burst dataset (or automatically detected BD files) on each data recorders as much as possible, and all SD are dumped to the ground prior to BD. Quick looking SD, the science team decides the dump priority of BD files and higher priority BD files are dumped to the ground.

The international science team have to determine the BD file priority as soon as possible. The current estimation shows that about 10 minutes BD can be transferred to the ground during a 8-hours real-time tracking pass. With the TByte calss data storage, all the BD can be stored for 6 days. Thus, the science team have to decide the data download priority within a couple of days.