Satellite/debris drag
Moderator:
The major source of uncertainty in determining the precise orbital location of objects in Low Earth Orbit is the computation of the acceleration due to atmospheric drag, which is heavily dependent on the density of neutral molecules and atoms in Earth’s thermosphere. Neutral density is highly variable, both spatially and temporally, and is driven by heating due to solar EUV emissions, geomagnetic activity (i.e. solar wind interaction with the upper atmosphere in the auroral zones), radiative cooling, and to a lesser extent tidal effects from Earth’s lower atmospheric layers. The uncertainty in drag computation and prediction has two main causes: the first is due to the model error, whereas the second is independent of model error and entirely due to errors in the forecast of solar and geomagnetic activity proxies or indices.
There are five major problem areas in orbit computation due to atmospheric drag that are impacted by our uncertain knowledge of atmospheric neutral density. These areas are:
- Operational Orbit Prediction
- Conjunction Analysis
- Satellite Catalog Accuracy
- Reentry Modeling
- Mission Analysis (’25-year re-entry rule’)
Relevant Clusters
