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Maria:
North:
1- Mare Frigoris (Sea of
Cold)
2- Mare Imbrium (Sea of
Rains)
3- Sinus Aestuum (Bay of Seething)
Northeast:
4- Sinus Medii (Bay of the
Center)
5- Mare Vaporum (Sea of
Vapors)
6- Mare Serenitatis (Sea of
Serenity)
7- Mare Tranquillitatis (Sea of
Tranquillity)
8- Mare Crisium (Sea of Crises)
17-
Lacus Somniorum (Lake of Sleep)
18- Palus Somnii (Marsh of
Sleep)
19- Mare Anguis (Sea of Snakes)
20- Mare Undarum (Sea
of Waves)
Southeast:
9- Mare Fecunditatis (Sea of
Fecundity)
10- Mare Nectaris (Sea of Nectar)
21- Mare Spumans
(Sea of Foam)
Southwest:
11- Mare Nubium (Sea of Clouds)
12- Mare
Humorum (Sea of Moisture)
13- Mare Cognitum (Known Sea)
22-
Palus Epidemiarum (Marsh of Diseases)
West:
14- Oceanus Procellarum (Ocean of Storms)
Northwest:
15- Sinus Roris (Bay of Dew)
16- Sinus
Iridum (Bay of Rainbows)
Montes (Mountains):
Northeast:
23- Montes Alpes
24-
Vallis Alpes (Alpine Valley)
25- Montes Caucasus
26- Montes
Apenninus
27- Montes Haemus
28- Montes Taurus
Southeast:
29- Montes Pyrenaeus
Southwest:
30- Rupes Recta (Straight Wall) [Geological
Fault]
31- Montes Riphaeus
Northwest:
32- Vallis Schröteri (Schröter's Valley)
[Northwest of Crater Aristarchus, 73, and North of Crater
Herodotus]
33- Montes Jura
Craters:
Northeast:
34- Crater Aristotle [on the
East part of Mare Frigoris, 1]
35- Crater Cassini
36- Crater
Eudoxus
37- Crater Endymion
38- Crater Hercules
39-
Crater Atlas
40- Crater Mercurius
41- Crater
Posidonius
42- Crater Zeno
43- Crater Le Monnier
44-
Crater Plinius
45- Crater Vitruvius
46- Cráter
Cleomedes
47- Crater Taruntius
48- Crater
Manilius
49- Crater Archimedes
50- Crater
Autolycus
51- Crater Aristillus
Southeast:
52- Crater Langrenus
53- Crater
Goclenius
54- Crater Hypatia
55- Crater
Theophilus
56- Crater Rhaeticus [Crater Hipparchus is directly South of
Crater Rhaeticus]
57- Crater Stevinus
58- Crater
Ptolemaeus
59- Crater Walter
Southwest:
60- Crater Tycho
61- Crater
Pitatus
62- Crater Schickard
63- Crater Campanus
64-
Crater Bulliadus
65- Crater Fra Mauro
66- Crater
Gassendi
67- Crater Byrgius
68- Crater Billy [Mons Hansteen is
to the North of Crater Billy]
69- Crater Crüger
70- Crater
Grimaldi
71- Crater Riccioli
Northwest:
72- Crater Kepler
73- Crater Aristarchus
[Crater Herodotus is West of Crater Aristarchus]
74- Crater
Copernicus
75- Crater Pytheas
76- Crater Eratosthenes [near
the Southwestern extreme of Montes Apenninus, 26]
77- Crater
Mairan
78- Crater Timocharis
79- Crater Harpalus [Crater
Pythagoras is North of Crater Harpalus]
80- Crater Plato
This Moon map was provied by Observatorio ARVAL - Caracas, Venezuela. at http://www.oarval.org/MoonMapen.htm
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Astronomical Bases of Calendars
The principal astronomical cycles are the day (based on the
rotation of the Earth on its axis), the year (based on the
revolution of the Earth around the Sun), and the month (based on
the revolution of the Moon around the Earth). The complexity of
calendars arises because these cycles of revolution do not comprise
an integral number of days, and because astronomical cycles are
neither constant nor perfectly commensurable with each other.
The tropical year is defined as the mean interval
between vernal equinoxes; it corresponds to the cycle of the
seasons. The following expression, based on the orbital elements of
Laskar (1986), is used for calculating the length of the tropical
year:
365.2421896698 - 0.00000615359 T - 7.29E-10 T^2 + 2.64E-10 T^3
[days]
where T = (JD - 2451545.0)/36525 and JD is the Julian day number.
However, the interval from a particular vernal equinox to the next
may vary from this mean by several minutes.
The synodic month, the mean interval between
conjunctions of the Moon and Sun, corresponds to the cycle of lunar
phases. The following expression for the synodic month is based on
the lunar theory of Chapront-Touze' and Chapront (1988):
29.5305888531 + 0.00000021621 T - 3.64E-10 T^2 [days].
Again T = (JD - 2451545.0)/36525 and JD is the Julian day number.
Any particular phase cycle may vary from the mean by up to seven
hours.
In the preceding formulas, T is measured in Julian centuries of
Terrestrial Dynamical Time (TDT), which is independent of the
variable rotation of the Earth. Thus, the lengths of the tropical
year and synodic month are here defined in days of 86400 seconds of
International Atomic Time (TAI).
From these formulas we see that the cycles change slowly with
time. Furthermore, the formulas should not be considered to be
absolute facts; they are the best approximations possible today.
Therefore, a calendar year of an integral number of days cannot be
perfectly synchronized to the tropical year. Approximate
synchronization of calendar months with the lunar phases requires a
complex sequence of months of 29 and 30 days. For convenience it is
common to speak of a lunar year of twelve synodic months, or
354.36707 days.
Three distinct types of calendars have resulted from this
situation. A solar calendar, of which the Gregorian
calendar in its civil usage is an example, is designed to maintain
synchrony with the tropical year. To do so, days are intercalated
(forming leap years) to increase the average length of the calendar
year. A lunar calendar, such as the Islamic calendar,
follows the lunar phase cycle without regard for the tropical year.
Thus the months of the Islamic calendar systematically shift with
respect to the months of the Gregorian calendar. The third type of
calendar, the lunisolar calendar, has a sequence of months
based on the lunar phase cycle; but every few years a whole month
is intercalated to bring the calendar back in phase with the
tropical year. The Hebrew and Chinese calendars are examples of
this type of calendar.
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Image
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Astro
Stuff Planisphere