[rx]

Does the ratio of the circumference to the diameter do anything for you? It wouldn't likely be actual aliens, but it could well be their self-activating software:

The (underlying) image at left is an extremely high resolution example of what is believed to be Extra-Terrestrial-generated software (note the ratchets that are similar to the crop circle at right, where π is represented to 10 digits). Prior to this example (at right) from 2008, using such a ratchet system was not known ever to be used to represent a number (without digits as we know them).

[arrogantsob]

I may be the arrogantsob but that went right by my head at a rapid pace.