What it is and the problem it solves
Satellite imagery is remote sensing from space. It solves the problem of observing Earth at scale, frequency, and altitude unreachable by aircraft or ground surveys.
How it works
Satellite imagery captures light and radiation from Earth using sensors aboard rockets and satellites. It detects across visible, infrared, and radar bands of the electromagnetic spectrum. Spatial resolution depends on sensor instantaneous field of view. Spectral resolution depends on wavelength interval size and number of intervals measured. Temporal resolution is the time between successive image collections for a given location.
What works
Sub-orbital V-2 rocket flights in 1946 captured the first space images—reaching 105 km, five times higher than the prior balloon record. Orbital imaging began with Explorer 6 on 14 August 1959. Real-time acquisition began with KH-11 in 1977. Resolution characteristics are rigorously defined and measurable—not aspirational.
What does not
It does not deliver uniform resolution across all dimensions. Spatial, spectral, temporal, radiometric, and geometric resolution vary by instrument and orbit—and cannot be improved simultaneously. Real-time acquisition began in 1977, but remains constrained by downlink bandwidth, processing infrastructure, and orbital mechanics.
What it changes
It changes how we monitor environmental change, map terrain, verify treaties, and assess disaster impact—by replacing episodic, ground-based observation with systematic, repeatable, wide-area measurement.
Is it worth your time
Yes—if your work requires consistent, repeatable observation of large or inaccessible areas over time. No—if you need sub-metre detail daily, or real-time video without latency or classification delays.
