PROBLEMS
OF A UNIFORM SELENODETICAL COORDINATE SYSTEM CONSTRUCTION FOR GLOBAL MAPPING OF
THE MOON
M.I.Shpekin
Kazan state university
msh@ksu.ru
The idea of the complete Moon mapping has been
put forward by professor B.N.Rodionov in 1966. The author suggested surveying
Moon for 14 days from the polar satellite orbit. In the project it
was supposed, that obtained images of a lunar surface would be processed by
analytical photogrammetry methods that would allow creating selenodetical basis
for the Moon global mapping.
Unfortunately, for the past 40 years the
problem has not found its solution, despite of numerous surveying of the Moon
by various space vehicles. Apparently, more similar approach to the
professor Rodionov’s project was used by authors of the scientific program
carried out within the scientific work on the launching of
"Lunar-Orbiter" satellites during preparation of SS
"Apollo" ground landing. These satellites have been launched
into polar orbits and have photographed practically all surface of the Moon. However,
observations from "Lunar-Orbiter" satellites have been executed by
photo television film-making systems and did not possess measuring
characteristics suitable for construction of photogrammetrical networks.
Photographic systems of SA "Probe"
and SA "Apollo" series have finished surveying lunar surface by
cameras with metric precision, but the territory covered by survey has appeared
insufficient for construction of lunar global coordinate system. The
further surveying of the Moon have been concentrated basically on the
geological mapping.
Now at the same time several countries plan
launching of space vehicles on circumlunar orbits. However, none of
the projects, except of the program developed by the Chinese experts, does
contain any obvious mention of mapping survey of the Moon. One
gets the impression, that the problem of global
mapping of the Moon has been already solved. It should be
noted that it is far from true. Despite of the significant studies carried out
by scientific staff of academic and industrial organisations such as GAISh,
MIIGAiK, TsNIIGAiK, IKI and GEOKhi of the Russian Academy of Science, NPO
"Energy", S.A.Lavochkin ÎÊB , and etc., many problems are still far
from their decisions. For the visible side of the Moon the lunar
coordinates system is realized with errors not less than 1 km. For
the rim zone and, especially, for the other side of the Moon the situation is
much worse. Such accuracy does not meet the requirements of
the navigating problems in circumlunar space. Such accuracy
cannot be considered comprehensible for topographical mapping of the Moon.
The moon represents an ideal heavenly body from
the point of view of construction on it a global precision coordinates system
for that simple reason, that on the Moon there is no atmosphere, and
film-making routes can be made closed. On the Earth the similar scheme of
surveying could not be realizable as the most part of the planet is covered
oceans.
Experience of coordinate systems construction
on the Moon shows that it is a complex scientific and technical problem which
solving requires involvement of experts from industry, science and education.
The analysis of the published projects allows
to suppose, that their authors consider incompletely the previous experience of the Moon
observation. So, for example, the aspiration to launch the
satellite into a low orbit (50-100 km) is not the best decision for creation of
the lunar global coordinates system.
Also, other aspects of creation of uniform
coordinates system of the Moon are considered which demand on detailed
discussion and deep, total study.