What Is Earth Observation? How Satellites Image Our Planet

Earth observation (EO) is one of the largest commercial applications of space technology. Hundreds of satellites image the planet daily, generating data used across agriculture, insurance, defense, environmental monitoring, and urban planning.

How Satellite Imaging Works

• Optical (visible/near-infrared): Digital cameras in space capturing reflected sunlight. Resolution ranges from 30cm (military/commercial high-res) to 300m (weather satellites). Requires clear skies and daylight
• Synthetic Aperture Radar (SAR): Active radar that generates its own signal. Works through clouds, at night, and in all weather. Companies like Capella Space and ICEYE offer SAR imagery
• Multispectral: Captures light across multiple wavelength bands (visible + infrared). Used for vegetation health (NDVI), water quality, and mineral detection
• Hyperspectral: Captures hundreds of narrow wavelength bands. Identifies materials by their spectral signature. Used for mining exploration and environmental monitoring

Key EO Operators

• Planet Labs: Operates the PlanetScope (SuperDove) and SkySat Earth observation constellations
• Vantor (formerly Maxar Intelligence, renamed in October 2025): Operates the WorldView Legion constellation
• Airbus: Pleiades Neo constellation at 30cm resolution. Strong European government customer base
• BlackSky: Monitoring constellation built for frequent revisits of priority targets

Applications

• Agriculture: Precision farming: monitor crop health, predict yields, detect irrigation issues across millions of acres
• Insurance: Damage assessment after natural disasters, property verification, and risk modeling
• Defense: Intelligence gathering, change detection, maritime domain awareness
• Climate: Deforestation monitoring, ice cap measurement, emissions tracking (methane plumes visible from space)

Track EO satellites and constellations at SpaceNexus Satellite Tracker.