Satellite and Aerial Imagery
What This Is
Satellite and aerial imagery gives an overhead view of a location for confirmation, monitoring, and change analysis. It confirms the geometry deduced from a ground-level photo, reveals features not visible from the street, and, through historical archives, shows how a site changed over time. Free sources cover most investigations, with commercial providers filling gaps in resolution and recency.
When to Use This
Use overhead imagery when you need to:
Confirm a location deduced from a ground photo against its overhead footprint
Inspect a site that has no street-level coverage
Establish when a structure was built, modified, or removed
Monitor activity at a fixed location across time
The Workflow
Begin with the highest-resolution free base layer for the area, usually Google Earth or Esri World Imagery, to confirm the footprint. When timing matters, move to archives with a date slider to compare acquisitions. For recent or frequent coverage, drop to medium-resolution but fast-refreshing sources such as Sentinel-2, and only escalate to commercial tasking when free coverage is insufficient.
Subpages
Satellite Imagery Sources and Access: where to obtain free and commercial overhead imagery
Historical Imagery and Change Detection: compare acquisitions over time to date and track changes
OpSec Note
Browsing public imagery archives is passive and leaves no trace with the target. Requesting new commercial tasking over a specific site is not passive: it creates a record with the provider tying your account to an interest in that location. Prefer existing archive imagery unless fresh capture is essential.