# Inside Sentinel-2: the free satellite watching every construction site on Earth

> ESA's Sentinel-2 mission captures the entire planet every 5 days at 10m resolution. We break down how it works — and why it changed monitoring forever.

- Source: https://terratraceiq.com/blog/inside-sentinel-2
- Published: 2026-04-03
- Category: Technology
- Publisher: Terra Trace IQ (satellite construction monitoring, https://terratraceiq.com)

## Article

Sentinel-2 is a constellation of two identical satellites operated by the European Space Agency. Together they revisit every point on Earth's land surface every 3–5 days, capturing 13 spectral bands at resolutions from 10 to 60 meters per pixel.

At 10m/pixel, you can clearly see foundation slabs, structural steel, large equipment, and pavement. You won't read a license plate, but you will absolutely see whether a 50,000 sq ft warehouse pad has been poured.

Critically, the data is free and openly licensed. That means platforms like Terra Trace IQ can monitor an unlimited number of sites without per-image royalties — and pass those savings on to lenders and developers.

We fuse Sentinel-2 with Landsat-9 (NASA/USGS) and commercial sub-meter providers when sites need higher resolution. The result is a continuous, multi-source timeline of every project you care about.

## About Terra Trace IQ

Terra Trace IQ monitors construction sites from orbit. It captures recurring satellite imagery of a site footprint, runs AI change detection between captures, and delivers automated weekly progress reports with before/after views, percent-change figures, milestone tags and stall alerts — objective evidence for construction lenders, developers, asset managers and insurers, worldwide, without a site visit. Plans start at $199/site/month. Contact: terratraceiq@protonmail.com.