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+# KSA Artemis OEM Loader
+
+This is a quick mod for [Kitten Space Agency](https://ahwoo.com/app/100000/kitten-space-agency)
+intended to allow loading of real-world orbit data from the Artemis II mission.
+
+It accepts input in the form of CCSDS OEM (Orbit Ephemeris Message) files, although it is very
+quick and dirty and makes a lot of assumptions about both the files and KSA (in fact, it doesn't
+read the metadata in the files at all!) These assumptions should be sufficient for loading Artemis
+II ephemeris data reasonably correctly, but this mod probably won't work with other OEM files
+(contributions are welcome).
+
+## Installation
+
+SpaceDock page coming soon
+
+## Usage
+
+To open the OEM loader window, go to View > Ephemeris Loader in KSA.
+Enter the path to your OEM file in the text box, and press "Load OEM file".
+
+OEM files for the Artemis II mission are available from NASA at
+https://www.nasa.gov/missions/artemis/artemis-2/track-nasas-artemis-ii-mission-in-real-time/.
+The OEM file is zipped, so you'll need to extract it before loading.
+NASA's OEM files seem to be wrapped in an HTML document, but the parser in this mod
+is very quick and dirty and will ignore everything in the file except the actual
+orbit data lines, so you don't actually need to do anything about this.
+
+Once you have successfully loaded an OEM file, there will be some more buttons
+in the GUI. Press "Go to now" to set the orbit of the current vehicle to the orbit
+from the OEM file at the current real-world time. (Note that time=zero in KSA is
+actually sometime in November 2025.) Alternatively, use the slider to select a time
+and press "Go to <time>" to set the current vehicle's orbit. (This works even if the
+selected time is in the past relative to the current game time.)
+
+Note that the orbit is not automatically updated from the ephemeris after pressing
+the button, so if you are tracking Artemis in real-time, you will need to periodically
+press the Go to Now button to keep the orbit accurate.
+
+## Note
+
+This mod has only been tested with the Linux build of KSA, but should work fine on
+Windows too.
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