|Landsat-8 satellite image of Fort Collins, Colorado, taken on March 18, 2013. Images courtesy NASA.|
Back when I started my remote-sensing career, Landsat images were sold through a for-profit company that charged $4,400 per image (even though the entire system was taxpayer-built and operated). Happily, now you can download every single Landsat image for free and do your own skytruthing. Let us know what you find!