Blog
Tutorials, case studies, and technical insights on satellite imagery analysis.
Active Fire Monitoring with NASA FIRMS: Real-Time Hotspot Detection from Space
NASA FIRMS provides near real-time fire hotspot data from VIIRS and MODIS satellites. Learn how active fire monitoring works, what the data shows, and how to use it in Off-Nadir Delta for wildfire tracking and disaster response.
SAR vs Optical Satellite Imagery: A Practical Guide to Choosing the Right Sensor
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.
Estimating Soil Moisture with SAR: Why Radar Sees What Optical Can't
How SAR backscatter responds to soil moisture content, the physical basis for radar-based soil moisture estimation, and practical challenges including vegetation cover and surface roughness effects.
NISAR and L-Band SAR: What Changes When You Double the Wavelength
NASA-ISRO's NISAR mission brings L-band SAR to routine global monitoring. This post explains what L-band sees that C-band doesn't, why it matters for biomass and deformation studies, and how to prepare for the data.
Geometric Correction and Orthorectification of Satellite Imagery
Why raw satellite images are geometrically distorted and how orthorectification corrects them using sensor models, ground control points, and digital elevation models. Covers the difference between georeferencing, geocoding, and orthorectification.
GeoTIFF and Cloud-Optimized GeoTIFF: What's the Difference and Why It Matters
Cloud-Optimized GeoTIFF (COG) is becoming the standard for satellite data distribution, but many users don't understand what makes it different from a regular GeoTIFF. This post explains the internal structure, performance benefits, and practical implications.
SAR Coherence for Change Detection: Finding What Changed Without Optical Data
How SAR coherence maps reveal surface changes even through clouds and at night. Understand temporal coherence, its relationship to surface stability, and practical applications in disaster assessment and construction monitoring.
SAR Speckle Noise: What It Is and How to Filter It Without Losing Information
Understanding the granular noise pattern in SAR imagery, why it exists, and practical filtering approaches including Lee, Frost, and multi-temporal averaging. When to filter and when speckle carries useful signal.
VV, VH, HH, HV: SAR Polarization Demystified
SAR polarization modes determine what you see in radar imagery. This post explains the physics behind polarization, why Sentinel-1 uses VV and VH, and how to choose the right polarization for your application.
Hyperspectral Remote Sensing: What 200+ Bands Reveal That Multispectral Can't
How hyperspectral satellites like PRISMA and EnMAP capture hundreds of narrow spectral bands, enabling mineral identification, crop stress detection, and water quality analysis beyond multispectral capabilities.
InSAR: How Satellites Measure Millimeter Ground Movement from 700 km Up
Interferometric SAR (InSAR) explained — how phase differences between two SAR acquisitions reveal ground deformation, subsidence, and tectonic movement with millimeter precision. Covers differential InSAR, coherence, and real-world applications.
How to Choose the Right Satellite Data for Your Project
With dozens of satellite data sources available, picking the right one for your specific analysis can be overwhelming. This decision guide walks through the key questions to ask before you start.