This short article will teach you how to check for yourself that:

1) Satellites are taking pictures of the ground and sending those pictures back

2) They have been doing that for years

3) Those pictures match what happens in the ground

4) The cronologial order that those pictures are taken is consistent with the trajectory of satellites spinning around the globe.

Two of the most widely used satellites for geoprocessing are LANDSAT7 and LANDSAT8. Their images are available for download for free by anyone.

To be able to open those images, it’s best to use appropriate software that can work with georeferenced files. QGIS is a great free open source option for that. Download QGIS.

With QGIS you can open shapefiles (files that end with .shp) and some other file types as well. A shapefile is a vectorized map where the coordinates are somehow related to lat-lon coordinates. Now here’s two useful shapefiles that any geoprocessing professional must have: 1) a world map, and 2) LANDSAT tiles. You can open both of those files at the same time (just drag and drop the shp files on QGIS). Here I have LANDSAT tiles as a transparent layer over the world map. The tiles are important because the pictures you can download are associated with each tile. Every tile gets a new picture every 16 days.