One scenario would be if it scanned it once in 8 days and once in 4 days, due to, say, an elliptical orbit or something. Thus, twice in 12 days, but not once every 6 days.
Alternately, complex orbital tracks may result in irregular accumulation of multiple scans, with double scanning only finally being achieved after 12 days.
I think it's because they're scanning in two different wavelengths:
In a first, the satellite combines two synthetic aperture radar (SAR) systems: an L-band system that can see through clouds and forest canopy, and an S-band system that can see through clouds as well but is more sensitive to light vegetation and moisture in snow.
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Very topical item, with NISAR unfurling to it's full 39 foot deployment up in space.
https://www.jpl.nasa.gov/news/giant-radar-antenna-reflector-...
“The mission scans nearly all the planet’s land and ice surfaces twice every 12 days.” What was wrong with saying once every 6 days?
One scenario would be if it scanned it once in 8 days and once in 4 days, due to, say, an elliptical orbit or something. Thus, twice in 12 days, but not once every 6 days.
Alternately, complex orbital tracks may result in irregular accumulation of multiple scans, with double scanning only finally being achieved after 12 days.
I think it's because they're scanning in two different wavelengths:
Whoa incredible! Can you believe it does four scans every 24 days?!