We all love the glorious moon. We can keep staring it for a long time and it make us feel happy, feel nice from inside. We all love it. But do we know how it came into existence, it’s details . Have we ever bothered to think so deep with it ….May be no , may be yes.

Today, I am going to be the tour guide for detailing this beautiful moon.
The Moon is an astronomical body that moves around our Earth. This is the Earth’s only permanent natural satellite and the fifth-largest natural satellite in the Solar System. Our Moon is the second-densest satellite in the Solar System.
Moon rotate synchronously with Earth, always showing the same face, with its near side marked by dark volcanic maria that fill the spaces between the bright ancient crustal highlands and the prominent impact craters. As seen from the Earth, it is the second-brightest regularly visible celestial object in Earth’s sky, after the Sun. But you know, it’s surface is actually dark.

Now, you will be thinking why it is so bright then!!!

In our solar system, the planets and their moons receive light from the Sun, so our Moon does the same. When the moon appears to glow, it is actually bouncing the sunlight to the earth where we’re viewing it. It also reflects light during the day but due to the sun’s visibility and it’s immense light makes its glow less and does not visible in daylight.

Oddly enough, the moon shouldn’t be very good at bouncing light. Have you ever stepped outside on a sunny, snowy day and needed to put on your sunglasses? White objects are great at bouncing light. This means that they reflect light well. But moon’s surface is black right!!!

It’s because when light hits the rough soil of the moon directly and the person watching the moon from Earth is in a line with the sunlight. Thus, the shadows of the moon’s soil seem to disappear, making the moon look brighter.


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

How our Moon form???

The giant-impact hypothesis, sometimes called the Big Splash, or the Theia Impact suggests that the Moon formed out of the debris left over from a collision between Earth and an astronomical body had the size of Mars, approximately 4.5 billion years ago, after the solar system coalesced. The colliding body is sometimes known as Theia. Analysis of lunar rocks, published in a 2016 report, suggests that the impact may have been a direct hit, causing a thorough mixing of both parent bodies.

The giant-impact hypothesis is currently the favoured scientific hypothesis for the formation of the Moon. Supporting evidence includes:

  • Earth’s spin and the Moon’s orbit have similar orientations.
  • Moon samples indicate that the Moon’s surface was once molten.
  • The Moon has a relatively small iron core.
  • The Moon has a lower density than Earth.
  • There is evidence in other star systems of similar collisions, resulting in debris disks.
  • Giant collisions are consistent with the leading theories of the formation of the Solar System.
  • The stable-isotope ratios of lunar and terrestrial rock are identical, implying a common origin.

Structure

The Moon has a geochemically distinct crust, mantle, and core. It has a solid iron-rich inner core with a radius possibly as small as 240 km (150 mi) and a fluid outer core primarily made of liquid iron with a radius of roughly 300 km (190 mi). Around the core is a partially molten boundary layer with a radius of about 500 km (310 mi).

This structure is thought to have developed through the fractional crystallization of a global magma ocean shortly after the Moon’s formation 4.5 billion years ago. Crystallization of this magma ocean would have created a mafic mantle from the precipitation and sinking of the minerals olivine, clinopyroxene, and orthopyroxene. After about three-quarters of the magma ocean had crystallised, lower-density plagioclase minerals could form and float into a crust atop. The final liquids to crystallise would have been initially sandwiched between the crust and mantle, with a high abundance of incompatible and heat-producing elements. Consistent with this perspective, geochemical mapping made from orbit suggests the crust of mostly anorthosite. The Moon rock samples of the flood lavas that erupted onto the surface from partial melting in the mantle confirm the mafic mantle composition, which is more iron-rich than that of Earth. The crust is on average about 50 km (31 mi) thick.

The Moon is the second-densest satellite in the Solar System. However, the inner core of the Moon is small, with a radius of about 350 km (220 mi) or less, around 20% of the radius of the Moon.

Analyses of the Moon’s time-variable rotation suggest that it is at least partly molten.

Geological Feature of Moon

The most visible topographic feature is the giant far side South Pole-Aitken basin, which has the lowest elevations of the Moon and the highest elevations are found just to the north-east of this basin. It has been suggested that this area might represent thick ejecta deposits that were emplaced during an oblique South Pole-Aitken basin impact event. Other large impact basins, such as the mariaImbrium, Serenitatis, Crisium, Smythii, and Orientale, also possess regionally low elevations and elevated rims.

Another distinguishing feature of the Moon’s shape is that the elevations are on average about 1.9 km higher on the far side than the near side. If it is assumed that the density of the crust everywhere is same, then the higher elevations would be associated with a thicker crust.

Using gravity, topography and seismic data, the crust is thought to be on average about 50 ± 15 km thick, with the far-side crust being on average thicker than the near side by about 15 km.

Volcanic Feature

The dark and relatively featureless lunar plains, clearly seen with the naked eye, are called maria as they were once believed to be filled with water. They are now known to be vast solidified pools of ancient basaltic lava.

Impact Crater

Moon’s surface is impact cratering with craters formed when asteroids and comets collide with the lunar surface. There are estimated to be roughly 300,000 craters wider than 1 km (0.6 mi) on the Moon’s near side alone. The lunar geologic timescale is based on the most prominent impact events, including Nectaris, Imbrium, and Orientale, structures characterized by multiple rings of uplifted material.

Lunar Swirls

Lunar swirls are enigmatic features found across the Moon’s surface, which are characterized by a high albedo, appearing optically immature and often displaying a sinuous shape. Their curvilinear shape is often accentuated by low albedo regions that wind between the bright swirls.

Presence of Water

Since the 1960s, scientists have hypothesized that water ice may be deposited by impacting comets or possibly produced by the reaction of oxygen-rich lunar rocks and hydrogen from solar wind, leaving traces of water which could possibly persist in cold, permanently shadowed craters at either pole on the Moon.

Atmosphere and The Gravitional Field

The Moon has an atmosphere so tenuous as to be nearly vacuum, with a total mass of less than 10 metric tons (9.8 long tons; 11 short tons). The surface pressure of this small mass is around 0.3 nPa. It varies with the lunar day. Its sources include outgassing and sputtering, a product of the bombardment of lunar soil by solar windions. Elements that have been detected include sodium and potassium,helium-4 and neon from the solar wind and argon-40, radon-222, and polonium-210, outgassed after their creation by radioactive decay within the crust and mantle.
The main lunar gravity features are mascons, large positive gravitational anomalies associated with some of the giant impact basins, partly caused by the dense mare basaltic lava flows that fill those basins.

Moon and Earth

The Moon makes a complete orbit around Earth with respect to the fixed stars about once every 27.3 days (its sidereal period). However, because Earth is moving in its orbit around the Sun at the same time, it takes slightly longer for the Moon to show the same phase to Earth, which is about 29.5 days.
The Moon is exceptionally large relative to Earth: a quarter its diameter and 1/81 its mass. It is the largest moon in the Solar System relative to the size of its planet.
The Moon is in synchronous rotation as it orbits Earth; it rotates about its axis in about the same time it takes to orbit Earth. This results in it always keeping nearly the same face turned towards Earth. However, due to the effect of libration, about 59% of the Moon’s surface can actually be seen from Earth. The side of the Moon that faces Earth is called the near side, and the opposite the far side.
The distance between the Moon and Earth varies from around 356,400 km (221,500 mi) to 406,700 km (252,700 mi) at perigee(closest) and apogee (farthest), respectively. On 14 November 2016, it was closer to Earth when at full phase than it has been since 1948.

So, this is all about the beautiful , Luminescent Moon for today.

I don’t wanna make you bored lots of details one at a time, may be sometime later again with more interesting fact.

Hope you enjoyed the tour …Bye.

7 thoughts on “Moon

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