January 27, 2016 - What Are Square Entrances Visible in Google Mars?
Please see https://www.youtube.com/watch?v=tgM7uBFdzVU
UPDATE: Is this the answer from an Earthfiles viewer?
January 27, 2016 email: “I believe these are digital anomalies from the stitching algorithm that Google uses. Notice the notches on the top right corner, and how the bottom of the square fades into a line where the color changes. There are notches on various edges of other examples, which remind me of the edge of pixels when magnified enough. They may be registration marks used to stitch together a landscape that isn’t sharp because of the distance from which the original shots were made. When the YouTube video talks about airbrushing or photoshopping out, I think the original algorithm probably puts these dots at the edges of each image panel and when they are assembled, they overlap enough to partially cover. Because these are long-distance shots with little on-ground detail, I don’t think Google ever expected anyone to magnify them this much. Keep up the good work.”
“These entrances are all different when it comes to the fine detail.
Some of them even seem to have something inside!” Google Mars search
posted December 5, 2015, by undergroundworldnews.com.