The Moon is the second brightest object in our sky. It can be visible in the day or night in its month-long journey around the Earth. It is the most recognisable object in the night sky and perhaps the easiest to observe. Features on the Moon, such as the darker rock of the 'seas' can be seen with the naked eye. Binoculars will show craters and mountains, telescopes will show smaller features. The brightness of the Moon makes it an easy object to photograph.

Viewed from the Earth, the Moon travels across the sky near to the path of the Sun. The Sun's path is called the ecliptic and is marked by the constellations of the zodiac. The first quarter Moon rises 6 hours after the Sun, the full Moon 12 hours after the Sun, and the third quarter Moon rises 6 hours before the sun.

Solar and Lunar eclipses can only occur at new Moon or Full Moon. They do not occur every new or full Moon because the path of the Moon's orbit around the Earth is 5 degrees different from the path of the Sun.

A full Moon rising over a distant horizon is a beautiful sight. The darker rock of the lunar 'seas' is very noticeable, but craters are not so easy to see. Best time to see craters and mountains are when they are near the lunar terminator - the dividing line between the sun-lit and the dark sides of the Moon. In this picture of a first quarter Moon from 23rd October 2020 you can see lots of craters to the left of 'Sea of Nectar'.

 The Moon from Chulmleigh, 23rd October 2020 (Grant Sherman)

In this photo taken two days later, the three big craters to the left of the 'Sea of Nectar' are not so easy to see (These craters are Theophilus, Cyrillus and Catharina). However other craters have become visible as the terminator has moved across the Moon's surface. As you watch the Moon through the course of its phases, you will see different craters illuminated every night.

The Moon from Chulmleigh, 25th October 2020 (Grant Sherman)


The Moon from Chulmleigh, 27th October 2020 (Grant Sherman)


British Astronomical Association The BAA Lunar Section has sub-sections covering occultations, TLPs, topography, geology and lunar imaging. The Lunar Section Circular is published at approximately monthly intervals. This contains general news and the results of the Section’s observational work. A second publication called The Moon, devoted to more detailed papers, is published at irregular intervals. 


Sky at Night Magazine 


Time and Date Half of the Moon’s surface is always illuminated by sunlight. However, just how much of that light we can see from our point of view on Earth varies every day and this is what we refer to as a Moon phase. 

The gravitational pull of the Moon and the Sun makes the water in the oceans bulge, causing a continuous change between high and low tide. 

Calendar of Moon phases 


Wikipedia The Moon is a gravity rounded astronomical body orbiting Earth and is the planet's only natural satellite. It is the fifth-largest satellite in the Solar System, and by far the largest among planetary satellites relative to the size of the planet that it orbits. The Moon is, after Jupiter's satellite Io, the second-densest satellite in the Solar System among those whose densities are known.

The Moon is thought to have formed about 4.51 billion years ago, not long after Earth. The most widely accepted explanation is that the Moon formed from the debris left over after a giant impact between Earth and a hypothetical Mars-sized body called Theia. New research of Moon rocks, although not rejecting the Theia hypothesis, suggests that the Moon may be older than previously thought.

The Moon is in synchronous rotation with Earth, and thus always shows the same side to Earth, the near side. Because of libration, slightly more than half (about 59%) of the total lunar surface can be viewed from Earth. The near side is marked by dark volcanic maria that fill the spaces between the bright ancient crustal highlands and the prominent impact craters. After the Sun, the Moon is the second-brightest celestial object regularly visible in Earth's sky. Its surface is actually dark, although compared to the night sky it appears very bright, with a reflectance just slightly higher than that of worn asphalt. Its gravitational influence produces the ocean tides, body tides, and the slight lengthening of the day.

The Moon's average orbital distance is 384,402 km (238,856 mi), or 1.28 light-seconds. This is about thirty times the diameter of Earth. The Moon's apparent size in the sky is almost the same as that of the Sun, since the star is about 400 times the lunar distance and diameter. Therefore, the Moon covers the Sun nearly precisely during a total solar eclipse. This matching of apparent visual size will not continue in the far future because the Moon's distance from Earth is gradually increasing.

The Moon was first reached by a human-made object in September 1959, when the Soviet Union's Luna 2, an uncrewed spacecraft, was intentionally crashed onto the lunar surface. This accomplishment was followed by the first successful soft landing on the Moon by Luna 9 in 1966. The United States' NASA Apollo program achieved the only human lunar missions to date, beginning with the first human orbital mission by Apollo 8 in 1968, and six human landings between 1969 and 1972, with the first being Apollo 11 in July 1969. These missions returned lunar rocks which have been used to develop a geological understanding of the Moon's origin, internal structure, and the Moon's later history. Since the 1972 Apollo 17 mission, the Moon has been visited only by un-crewed spacecraft.

Both the Moon's natural prominence in the earthly sky and its regular cycle of phases as seen from Earth have provided cultural references and influences for human societies and cultures since time immemorial. Such cultural influences can be found in language, lunar calendar systems, art, and mythology. 

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