Posidonius crater optical illusion Pictures through the telescope

Posidonius crater (95 km), is located on the north-east of the Moon. In the middle of the crater floor is another crater called Posidonius A (11 km). Photographs of  Moon craters viewed near, through  amateur astronomical telescopes, are tricky. If we tip over the picture, we see a different picture of those craters, without realizing that what we see are dimples, not heights, as in the article of the crater Copernicus optical illusion.

Another type of illusion, the craters in the normal position image, and one wich is overturned. In picture below, the small crater Posidonius A found in the large crater Posidonius in the first picture below is placed west of Posidonius's center point, and in the second picture, Posidonius A is on east of the center point. People used to see craters through a telescope are misled at first sight, because on Earth, craters on the Moon can be viewed only in a single position. Unless you look a whole Moon, from afar, you can figure out where that crater is.

At first impression, craters in the first photo below are located on the southwest quadrant of the Moon. In fact, if you look the above picture, you realize that they are on the northeast quadrant, but only if you look from afar. This illusion does not occur in other conditions when shadow of craters are positioned differently.

Figure 1 - normal
Figure 2 - overturned

Posted in: Craters-Posidonius,Optical illusions