Update README.md

Author: ADRyanHorgan

README.md

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 This document explains the Mission.Space Weather Extension to the [SpatioTemporal Asset Catalog](https://github.com/radiantearth/stac-spec) (STAC) specification.
 This is a work in progress extension, adding key field for Mission.Space's space weather data to the STAC specification.
+Our primary goal with this extension has been to ensure that Mission.Space's data is compatible with Data Sphere (Astro Dynamic's Earth Observation marketplace) which uses STAC as it's metadata format.
 The data made available on STAC is open sample data from Mission.Space, showing high energy particle activity measured by the their Zohar-1 instrument during minor and major geomagnetic storms.
 The assets are currently available as csv files, but this can be amended subject to feedback.