Model answer

Moderate-resolution sensors — the workhorses of regional and global Earth observation. Roughly 10 m to 250 m per pixel.

Examples: Landsat (30 m), Sentinel-2 (10 m), MODIS (250 m+).

Advantages

• Wide swaths — one pass covers an entire state.
• Frequent revisit when you combine satellites — Landsat + Sentinel-2 ≈ every 2–3 days globally.
• Long free archives — Landsat back to 1972, Sentinel-2 since 2015.
• Solid band selection for vegetation indices, water indices, fire mapping.

Disadvantages

• Can’t see individual objects — buildings, trees, single fields blur out.
• Mixed pixels at edges — a 30 m pixel might be half-forest, half-grassland.
• Clouds wreck many scenes — even with 16-day repeat, a lot of acquisitions are unusable.
• Thermal is coarser still — Landsat thermal is 100 m, resampled to 30 m for display.

The trade-off: you sacrifice fine detail for wide coverage and frequent revisit. For continental-scale science, that’s the right trade.

🔬 Show the science / technical version

• Examples: Landsat OLI (30 m), Sentinel-2 MSI (10–60 m), MODIS (250–1000 m).

Advantages

• Large swath — Landsat 185 km, Sentinel-2 290 km — regional/global coverage.
• Frequent revisit when combined (L8+L9+S2 ≈ every 2–3 days).
• Long free archives (Landsat → 1972).
• Multispectral breadth — NDVI, EVI, NBR, water indices.

Disadvantages

• Can’t resolve individual objects (buildings, small fields, trees).
• Mixed pixels at class boundaries hurt classification accuracy.
• Cloud contamination — 16-day repeat means many scenes unusable.
• Thermal resolution is coarser still (TIRS 100 m resampled to 30 m).