Judging from the picture on the right, the four dots must represent Venus, Jupiter, Saturn, Mars. As an aside, a circle with a cross inside of it like we see in the center of of this picture represents Earth. The Sun is at the Zenith of this picture and the Moon is at the Nadir. This is not a traditional astrological chart as it only has 8 rather than 12 houses (the pie pieces that are created by diameter lines). Usually each quadrant is divided into 3 houses rather than the 2 seen here. Also The symbol for Aries would normally be at the end of the left arm of the cross and the sign symbols would be reversed in order.
Ok. If you compare these two images and want to extrapolate what might be meant astrologically at the tennis court structure by analyzing the Masonic (I assume) image on the right, the indentations on the tennis court would represent in order, counter clockwise from left bottom would be Venus, Jupiter, Saturn, and Mars.
Also, look at the structure at the bottom of the Masonic? image. It is rectangular like the tennis court area. Each of the outer rectangles along the walls of the structure seem to contain something. I can make out a tree in the lower right hand corner. Did I see something like a thin, leafless tree in the tennis court area aerial pics. Need to go look again.