AlphaEarth (also called AlphaEarth Foundations or AEF in Google papers) encodes satellite-imagery semantics — typically as 64-dimensional embeddings in Planetary Prediction Engine write-ups. Google Research's PPE fuses those embeddings with tabular covariates and Population Dynamics Foundation Model vectors. They are used as frozen feature extractors rather than end-to-end fine-tuned per task; Google has noted that high-resolution satellite features can add noise at fine administrative scales.