This is a difficult one to call, to me it looks like a recent impact crater (notice the ejecta type spray), the image also has a look of being inverted and the square shape could be down to pixilation, "I suppose it could be a square building with underside illumination, but the crater behind also has the same light tone in the same position which makes me think the image has been inverted and the light tones are actually shadows.
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"Creating a fiction when stating a fact destroys the credibility of the truth one are trying to convey"
Just joined the group to share some anomalies that I believe I have found on the dark side of the moon (and of course, to view those that others have found).
The image here looks to me like a low, square building with internal illumination. Any thoughts? Have also found quite a few other things that look like they could be pylons, buildings and even a free floating craft (can post all if you'd like to see them), but we're all working from rather ill defined photos, so I appreciate it's so hard to tell. Anyway, first image is raw from Google Moon and the second is with contrast adjusted.