What free 10 m Sentinel-2 and Sentinel-1 imagery can and cannot show for the things OSINT analysts ask about: vehicles, buildings, ships, airfields, fires, floods and earthworks.
2026-10-04 · 7 min read
Satellite measurements are estimates, not ground truth. Learn the accuracy metrics that matter — RMSE, MAE, bias, R², confusion matrices, and cloud confidence — how to validate results, and how to communicate uncertainty honestly in any remote sensing analysis.
2026-06-21 · 5 min read
MODIS provides daily global coverage and a 20+ year archive at 250m-1km resolution. Learn what MODIS measures, its key products (NDVI, land surface temperature, active fire), how it trades resolution for frequency, and when coarse-resolution daily data beats high-resolution imagery.
2026-06-20 · 4 min read
A complete, structured guide to Synthetic Aperture Radar (SAR) for Earth observation — how SAR works, why it sees through clouds, polarization, backscatter, InSAR, and the full range of applications from flood mapping to ship detection. Your hub for every SAR topic.
2026-06-19 · 5 min read
Landsat is the longest continuous record of Earth's surface from space, running since 1972. Learn how Landsat 8 and 9 work, what their OLI and TIRS sensors measure, how the 30m archive enables long-term change detection, and how Landsat compares to Sentinel-2.
2026-06-18 · 5 min read
SAR and optical satellites measure fundamentally different things. This guide explains the physics, strengths, and limitations of each — and when to combine them for better results.
2026-02-10 · 6 min read
What orthorectification and geometric correction do to satellite images, why terrain causes distortion, and how DEMs and ground control points fix it.
2026-02-06 · 7 min read
Supervised and unsupervised classification compared: inputs, algorithms (Random Forest, k-means), accuracy assessment and when to use each for land cover.
2025-12-07 · 7 min read
A behind-the-scenes look at how Earth observation satellites acquire images. Understand pushbroom scanning, whiskbroom sensors, SAR synthetic aperture techniques, and why it matters for your data.
2025-12-01 · 7 min read
How satellite sensors convert raw digital numbers into meaningful reflectance or radiance values. Understand gain, offset, and why calibration is the first step in any serious analysis.
2025-11-21 · 7 min read
Spatial, spectral, temporal and radiometric resolution in remote sensing: what each means, typical values for common satellites, and the trade-offs.
2025-11-18 · 8 min read
What atmospheric correction does, why it matters for satellite data analysis, and what happens if you skip it. A practical explanation of TOA reflectance, BOA reflectance, and when correction is critical.
2025-11-15 · 8 min read
Why you can't have both high spatial and high temporal resolution from a single satellite. Understand the trade-off, how constellations address it, and how to choose the right balance for your project.
2025-11-05 · 7 min read
Sun-synchronous (SSO), polar and geostationary orbits explained: altitude, inclination and repeat cycle, with the orbits Sentinel-1/2 and Landsat fly.
2025-10-28 · 8 min read
Visible, NIR, red edge, SWIR, thermal and microwave bands in remote sensing: wavelength ranges, what each band reveals, and why atmospheric windows matter.
2025-10-22 · 8 min read
Remote sensing explained without the jargon. Learn how satellites collect data about Earth, the difference between active and passive sensors, and where this technology is actually used today.
2025-10-15 · 9 min read
Satellite imagery alone doesn't tell the whole story. Basemaps, boundaries, and infrastructure layers provide the geographic context needed for meaningful interpretation. This guide covers how to use reference layers effectively.
2025-08-06 · 7 min read
The colormap you choose changes what patterns you see in satellite data. This guide explains perceptual principles behind popular colormaps and when to use each one for different types of satellite imagery.
2025-07-20 · 7 min read
A practical guide to interpreting SAR backscatter values. Learn what sigma-nought represents, why it's measured in decibels, typical values for different land cover types, and how to avoid common interpretation mistakes.
2025-06-06 · 7 min read