A lawn looks simple from above. To a radar signal it is a dense, shifting population of biological scatterers: blades at different angles, water films, soil beneath, and movement from wind or handling.
Research objective—not demonstrated satellite performance. The target asks what carefully controlled observing systems can detect, and under what conditions.
Why a blade is not a clean measurement target
Radar response depends on wavelength relative to leaf dimensions, blade orientation, water content, canopy density, soil moisture, polarisation and incidence angle. Dew changes dielectric properties; wind changes orientation; growth and senescence change the scattering population. A repeat acquisition may therefore change even when the biological quantity of interest has not changed. These same factors can also decorrelate phase.
The 1.02 µm benchmark is a proposed sensitivity challenge. It does not mean that an orbital satellite can resolve an individual blade or directly observe one-micron growth. A statistical shift in a controlled aggregate signal is a different claim from spatially resolving a blade or measuring its tip displacement.
A credible experimental path
A first study would use calibrated bench or field instruments under controlled geometry, with independent optical or microscopic ground-truth measurements, environmental logging and repeated trials. It would vary moisture, orientation, canopy density and wind in a documented design. A preregistered analysis would estimate the smallest aggregate change that can be separated from noise and confounding conditions, then test it on held-out samples.
Only after a laboratory result survived replication would researchers ask what airborne or orbital observations could contribute. Each sensor has its own wavelength, footprint, sampling and revisit constraints. The research value lies in mapping those limits honestly and discovering which observing designs can answer which questions.
Demonstration panel
Observation sequence: 01 / 03