Tell About Moon?

Synodical – the length of time it takes the moon to circle the Earth, using the sun as the reference point (that is, the time lapse between two successive conjunctions with the sun – going from new moon to new moon): 29 days, 12 hours, 44 minutes, 2.7 seconds.

The Moon is slowly drifting away from Earth. Every year, the Moon moves roughly 3.8 cm further away from Earth. Scientific estimates suggest this will continue to happen for 50 billion years.

After the Sun, the Moon is the second-brightest regularly visible celestial object 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

It is the synodic month that is the basis of many calendars today and is used to divide the year.

You weigh much less on the Moon. A common fact about the Moon is that it has much weaker gravity than Earth. This is because its smaller mass and you would weight one sixth (about 16.5%) of your Earth weight while on the Moon.

Its gravitational influence produces the ocean tides, body tides, and the slight lengthening of the day.

We see slightly more than half of the moon from Earth
Most reference books will note that because the moon rotates only once during each revolution about the Earth, we never see more than half of its total surface.

Only 12 people have ever walked on the Moon. It started with Neil Armstrong in 1969 as part of the Apollo 11 mission and ended with Gene Cernan in 1972 on the Apollo 17 mission. A total of 12 American males have walked on the Moon. Since 1972, all lunar missions have been unmanned spacecraft.

The truth, however, is that we actually get to see more of it over the course of its elliptical orbit: 59 percent (almost three-fifths)

The Moon will be visited by man again. NASA has plans to set up a permanent space station on the Moon, and man may walk on the Moon again sometime around 2019-2020.

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.

The moon's rate of rotation is uniform but its rate of revolution is not, so we're able to see just around the edge of each limb from time to time.

The USA considered detonating a nuclear bomb on the Moon in the 50s. A secret project during the height of the cold war – codenamed “Project A119”, also known as “A Study of Lunar Research Flights” was planned as a “show of strength” at a time when they were falling behind the USSR in the space race.

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.

There is no atmosphere on the Moon. There is no protection for the surface from cosmic rays, meteorites, asteroids, comets, or solar winds. This is why the Moon has such huge temperature variations and it is covered with impact craters. The lack of atmosphere also means no sound can be heard on the Moon and the sky is always black.

Put another way, the two motions do not keep perfectly in step, even though they come out together at the end of the month. We call this effect libration of longitude.

The Moon was first reached in September 1959 by the Soviet Union's Luna 2, an unmanned spacecraft. The United States' NASA Apollo program achieved the only manned lunar missions to date, beginning with the first manned orbital mission by Apollo 8 in 1968, and six manned landings between 1969 and 1972, with the first being Apollo 11.

The Moon has quakes. The gravitational pull of Earth causes small moonquakes several kilometres beneath the surface – causing ruptures and cracks. It is believed that, like Earth, the Moon has a molten core.

So the moon "rocks" in the east and west direction, allowing us to see farther around in longitude at each edge than we otherwise could. The remaining 41 percent can never be seen from our vantage point; and if anyone were on that region of the moon, they would never see the Earth.

The Moon is the fifth largest natural satellite. It is much smaller than the major moons of Saturn and Jupiter at 3,475 km in diameter, but the Moon is the largest in relation to the size of the planet it orbits. Earth is about 80 times the volume of the Moon, yet they are the same age. A popular theory is that the Moon was once part of the Earth and formed from a chunk broken off by a huge object that collided with Earth while it was still young.

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.

The “Man in the Moon” is an optical illusion seen when looking at the Moon’s surface from Earth. It is a result of the contrast between the lighter lunar highlands and darker lunar plains.

It would take hundreds of thousands of moons to equal the brightness of the sun
The full moon shines with a magnitude of -12.7, but the sun is 14 magnitudes brighter, at -26.7. The ratio of brightness of the sun versus the moon amounts to a difference of 398,110 to 1. So that's how many full moons you would need to equal the brightness of the sun.

The diameter of the Moon is the same distance from New York City to Phoenix, Arizona.

Since the Apollo 17 mission in 1972, the Moon has been visited only by unmanned spacecraft.