Students will use remote sensing imagery and data to complete tasks related to Earth observation, including identifying land cover types, analyzing spectral data, and interpreting changes over time.
Convert between representative fraction and verbal scale
Calculate real-world distance from map measurements
Test your knowledge of spatial, spectral, temporal, and radiometric resolution
Match projections to their best uses
Explore synthetic satellite imagery. Click any cell to see its spectral values.
NDVI = (NIR - Red) / (NIR + Red)
Range: -1 to +1. Higher values = healthier vegetation
NDWI = (Green - NIR) / (Green + NIR)
Positive values indicate water bodies
NDMI = (NIR - SWIR) / (NIR + SWIR)
Indicates vegetation water content
Compare two scenes to detect environmental changes.
Complete a timed assessment mixing all remote sensing skills.
| Land Cover | Blue | Green | Red | NIR | SWIR | Key Feature |
|---|
| Projection | Type | Preserves | Best For |
|---|
| Type | Definition | Units | Examples |
|---|
| Index | Formula | Purpose | Value Range |
|---|---|---|---|
| NDVI | (NIR - Red) / (NIR + Red) | Vegetation health | -1 to +1 (>0.4 = healthy) |
| NDWI | (Green - NIR) / (Green + NIR) | Water detection | -1 to +1 (>0 = water) |
| NDMI | (NIR - SWIR) / (NIR + SWIR) | Moisture content | -1 to +1 (higher = wetter) |
| NDBI | (SWIR - NIR) / (SWIR + NIR) | Built-up areas | -1 to +1 (>0 = urban) |
| Representative Fraction | Verbal Scale | Type | Common Use |
|---|---|---|---|
| 1:1,200 | 1" = 100' | Very Large | Engineering plans |
| 1:24,000 | 1" = 2,000' | Large | USGS 7.5' quad |
| 1:50,000 | 1" ≈ 0.79 mi | Large | Topographic |
| 1:100,000 | 1 cm = 1 km | Medium | Regional planning |
| 1:250,000 | 1" ≈ 4 mi | Medium | State maps |
| 1:1,000,000 | 1" ≈ 16 mi | Small | World atlases |