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Lunar Anomalies. |
Gallileo's descriptions of the Moon's craggy and mountainous surface was at odds with the Religiously sanctioned view, that the Moon was a smooth perfect world as described by Aristotle. Some people were so shocked by what Gallileo was trying to say that even after looking at the Moon through his "optik tube" for themselves, they denied seeing anything that he described, or accused him of some kind of bewitchment.
This page is a look at some of the things that people claim to have seen on the surface of our Moon.
Because of the sheer breadth of material on this, I have decided to highlight the basic claims being made, rather than present a blow by blow account of the issues. The Cydonia Pages took forever to create and seeing as I am just summarising what I believe are the pertinent facts, there's no need to reproduce the Internet!
The Shard, The Lattice and the Castle
The Blair Cuspids
The Dome of Crisium
A conclusion
These can be:
The observer
The natural physical limitations of the human brain and senses. Forget the Hubble space telescope images. Much of what can been seen with the eye through a telescope is faint. A larger telescope helps, as it gathers more light. At low light levels it's the rods in the retina that gather information, the colour senstive cones need more light to work.
The telescope or camera/satellite
Because of the nature of light, a telescope (or camera) cannot focus a source like a star, as an infinitely small dot. Instead the light from a star is focused as a minute disc surrounded by fading rings, called a spurious disc. This disc can be measured at a finite size, and any detail on a planet or the moon, that is smaller in dimensions than the spurious disc will not be seen. The size of this disc is a function of size of the telescope's aperture.
Electronic detectors used in cameras also have their own limits due to resolution, electronic noise in the image, lighting, the attitude and motion of a satellite when taking a picture, image compression techniques and transmission.
The atmosphere
The quality of the "seeing" is a term used by astronomers to refer to how steady the air is. Light to a telescope has to travel through the atmosphere to get to the telescope, and it follows that if the atmosphere is turbulent then the light is going to be distorted by the time it reaches the astronomer. Fine details in images becomes lost and an object like the moon or a planet may appear to shimmer or boil through the telescope.
The object under observation
So far we have also neglected the issue of contrast. Many of the most dramatic views of the moon occur because of low lighting enhancing the effect of shadows. This makes small features or gentle undulations in the terrain stand out. Ironically features like rays from impact craters only stand out when lit from above i.e. full moon.
Perception
Visual observations of the sky are not as simple as just peering through a telescope. That are a number of factors that can trip up observers.
The left hand drawing is an exaggerated example of how a curved surface distorts shadows. The small brown block on the sphere and the cube is the same size, yet it casts a "longer" shadow on the curved surface. If we were observing the block face on instead of obliquely, and were not aware of the curved surface, then we might say that the block on the sphere was taller, as common sense tells us that tall objects cast longer shadows than smaller objects.
It's a fairly crude example, but it does demonstrate how the perceptual conventions we use on Earth do not always translate to interpreting what we see through a telescope.
The Mars Canal Effect - The human eye-brain, when confronted by fine detail, attempts to make sense of what it sees. This explains why we can see shapes in clouds, crystal balls, and canals on Mars. The same effect is at work when people over-process computer images and attempt to see details in the "noise" inherent in the image. Many many claims made about anomalies seem to be as a result of this process.
Just for interest, the following table shows us what a given range of telescopes with show us at their theoretical best. Perigee is when the Moon is at it's closest approach to us and apogee at it's farthest.
| Aperture | Smallest feature @ Perigee | Smallest feature @ Apogee |
| 25mm | 8.51km | 9.7km |
| 50mm | 4.57km | 5.2km |
| 80mm | 2.6km | 3.0km |
| 100mm | 2.13km | 2.4km |
| 200mm | 1.07km | 1.2km |
| 300mm | 710m | 808m |
| 600mm | 363m | 413m |
| 1m | 208m | 236m |
| 5m | 42m | 47m |
Now the truth is that once we account for poor seeing, average quality optics and an observer with average acuity, the smallest objects visible on the moon may be up to twice as large as what theory would predict.
The Moon has no atmosphere that would support animal life. We know this by two ways. Firstly, the Moon's path across the sky occasionally carries it in front of stars. When astronomers observe this, they see that the light from the star "snaps" off suddenly as it is occulted by the disc of the Moon. The presence of an atmosphere would instead cause the star to fade slowly, as it's light is attenuated through the layers of a lunar atmosphere. Secondly, using a similar method we could examine the light of the star with a spectroscope. A lunar atmosphere would cause a change in the spectrum of the star. This does not happen.
So, we can state fairly certainly that the Moon has no atmosphere. This also means that liquid water cannot exist on it's surface. Any water that is there would mostly be in the form of ice, perhaps from comets that have impacted the moon and remained shaded somewhere. The NASA probe Clemantine detected possible ice deposits in the polar regions of the Moon.
No atmosphere means that the surface of the Moon is subjected to the full spectrum of radiation from the sun. The temperature on the lunar surface ranges from -185ºC to 130ºC. The temperature 1m under the ground is a constant -35ºC. It's most unlikely that even microbes or bacteria would survive unprotected in such an environment.
revised 2007
