Moon Origin – Fission Theory (67)

Introduction

This is the third of the Moon Origin posts. This post explains the Fission Theory, which at the moment in scientific circles, has some validity but not enough to be considered a main contender.

The following excerpt comes from the book “Modern Mysteries of the Moon” by Vincent S. Foster.

The Fission Theory

“This is the idea that an ancient, rapidly spinning Earth expelled a piece of its mass. This theory was proposed by George Darwin (son of the famous biologist Charles Darwin) in the 1800s and retained some popularity until Apollo. The Austrian geologist Otto Ampherer in 1925 also suggested that the emerging Moon was cause for continental drift.

It was proposed that the Pacific Ocean represented the scar of this event. However, today it is known that the oceanic crust that makes up this ocean basin is relatively young, about 200 million years old or less, whereas the Moon is much older. However, the assumption that the Pacific is not the result of lunar creation does not disprove the fission hypothesis. This hypothesis also cannot account for the angular momentum of the Earth-Moon system, which is the gravitational torque between the Moon and the tidal bulge of Earth that causes the Moon to be constantly shifted to a slightly higher orbit and Earth to be decelerated in its rotation (Fig. 3.2 ).”

End (67).

Moon Origin – Capture Theory (66)

Introduction

This is the second of the Moon Origin posts. This post explains the Capture Theory, which at the moment in scientific circles, is popular but not as popular as the Giant Impact Theory. This theory just like the Giant Impact Theory has some holes. These holes are covered in this post.

The following excerpt comes from the book “Modern Mysteries of the Moon” by Vincent S. Foster.

The Capture Theory

“This hypothesis states that Earth captured the Moon. This was popular until the 1980s. Some things in favor of this model include the Moon’s size, orbit, and tidal locking. One problem is understanding the capture mechanism. A close encounter with Earth typically results in either collision or altered trajectories. For this hypothesis to work, the primitive Earth would had to have had an extended atmosphere around it, which would have been able to slow the movement of the Moon before it could escape. That may also explain the irregular satellite orbits of Jupiter and Saturn.

In addition, this hypothesis has difficulty explaining the identical oxygen isotope ratios of Earth and the Moon.”

End (66).

Moon Origin – Giant Impact Hypothesis - GIH (65)

Introduction

This is the first of the Moon Origin posts. This post explains the Giant Impact Theory, which at the moment in scientific circles, is the theory that it is most favoured. It is worth noting that this theory has some holes, that this there aspects about the Moon that this theory can not account for.

The following excerpt comes from the book “Modern Mysteries of the Moon” by Vincent S. Foster.

Giant Impact Hypothesis (GIH)

“The collision of two protoplanetary bodies during the early accretional period of Solar System evolution is the most widely accepted explanation for the origin of the Moon. This theory became popular in 1984. It satisfies the orbital conditions of Earth and the Moon and can account for the relatively small metallic core of the Moon. Collisions between planetesimals are now recognized to lead to the growth of planetary bodies. In this framework it is inevitable that large impacts will sometimes occur when the planets are nearly formed. The theory is thought to have originated in the 1940s with Reginald Aldworth Daly, head of the geology department at Harvard (Fig. 3.1 )

.

The colliding body is called Theia , the mother of Selene , the Moon goddess in Greek mythology. The hypothesis requires a collision between a body about 90 % the present size of Earth, and another the diameter of Mars (half of the terrestrial radius and a tenth of its mass). This size ratio is needed in order for the resulting system to possess sufficient angular momentum to match the current orbital configuration. Such an impact would have put enough material in orbit around Earth that could accumulate and eventually form the Moon.

Computer simulations show a need for a glancing blow, which would cause a portion of the colliding body to form a long arm of material that then would shear off. The asymmetrical shape of Earth following the collision would then cause this material to settle into an orbit around the main mass. The energy produced by this collision would have been impressive: trillions of tons of material would have been vaporized and melted. The temperature would have risen to 10,000 °C (18,000 °F).

The relatively small iron core of the Moon is explained by Theia ’s core accreting into Earth’s. The lack of volatiles in the lunar samples is also explained in part by the energy of the collision. The energy liberated during the re-accretion of material would have been sufficient to melt a large portion of the Moon, leading to the generation of a magma ocean.

The newly formed Moon orbited 90 % closer than it does today. It became tidally locked with Earth, where one side continually FIG. 3.1 The giant impact theory suggested that growing smaller planetary body (Mars-sized protoplanet) hit Earth about 4.5 billion years ago, blowing out rocky debris that was captured into orbit around Earth and coalesced into the Moon. NASA illustration  faces toward Earth. The geology of the Moon has since become more independent of Earth. Although this hypothesis explains many aspects of the Earth-Moon system, there are still unresolved problems with it, such as why the Moon’s volatile elements were not depleted as expected from such an energetic impact.

Comparisons of lunar and Earth isotopes is another issue. In 2011, the most precise measurement yet of the isotopic signatures of lunar rocks was published. Surprisingly, it showed that the Apollo lunar samples carried an isotopic signature identical to Earth rocks, but different from other Solar System bodies. Since most of the material that went into orbit to form the Moon was thought to come from Theia , this observation was unexpected. In 2007, researchers from Caltech found that the likelihood of Theia having an identical isotopic signature to Earth was very small (<1 %).

An analysis of titanium isotopes in Apollo lunar samples in 2012 revealed that the Moon has the same composition as Earth, which conflicts with the Moon forming far from Earth’s orbit. To help explain problems with this, a new theory was published by R. M. Canup in late 2012 which posits that two bodies five times the size of Mars collided, then re-collided, forming a large disc of debris that eventually formed Earth and the Moon.

Released at the same time was another study on the depletion of zinc isotopes on the Moon, which supported the giant impact origin for Earth and the Moon. In 2013, a study was released indicating that water in lunar magma was ‘indistinguishable’ from carbonaceous chondrites and nearly the same as Earth’s, based on the composition of isotopes. Another challenge was issued September 2013, with a growing sense that lunar origins are much more complicated than can be fully explained by the GIH theory.”

End (65).

Moon Origin (64)

Introduction

In the next series of five posts or so I plan to present the various leading theories to explain how the Moon came to be.

This post though is only an introduction to the current status of the Moon origin theories.

The following excerpt outlining the current status of the Moon origin theories comes from the book “Modern Mysteries of the Moon” by Vincent S. Foster.

Excerpt

“Scientists have offered several major theories to account for the origin of the Moon. All have drawbacks, but the favored theory that emerged from the Apollo missions was the Giant Impact Hypothesis (sometimes called the Big Splat ). This states that our Moon was created by a collision between Earth and a Mars-sized object some 4.5 billion years ago.

There are a number of variations and alternatives, including captured body, fission, formed together (condensation theory), planetesimal collisions (formed from asteroid-like bodies), and collision theories. All of the theories have been challenged, and none satisfy all questions.

NASA scientist Dr. Robin Brett sums it up best: “It seems much easier to explain the nonexistence of the Moon than its existence.””

Conclusion

There you have it, a valid theory explaining the origin of the Moon has not been settled upon yet, leaving the Moon’s presence still an unsolved mystery.

To esotericism though the origin of the Moon is very definite, and still to me this seems to be much more viable. That of which the Moon actually predates the Earth.

End (64).

Craters on the Moon – Ancient Volcanoes or Impacts (63)

Introduction

The following excerpts from “Modern Mysteries of the Moon” by Vincent S. Foster explains the process of how the large craters on the Moon were discovered to be due to impact rather than the result of ancient dried volcanoes. This discovery actually shone new light onto the topic of how the Moon has developed through time.

Moon Craters Originally Thought to be Volcanoes

Until the late 1800s, most astronomers thought that volcanism formed the craters of the Moon. In the 1870s, the English astronomer Richard A. Proctor proposed correctly that the craters resulted from the collision of solid objects with the Moon. But at first, few scientists accepted Proctor’s proposal. Most astronomers thought that the Moon’s craters must be volcanic in origin because no one had yet described a crater on Earth as an impact crater, but scientists had found dozens of obviously volcanic craters (Fig. 1.4 ).

Idea of Impact Craters Proposed by Gilbert

“In 1892, the American geologist Grove Karl Gilbert argued that most lunar craters were impact craters. He based his arguments on the large size of some of the craters. Those included the basins, which he was the first to recognize as huge craters. Gilbert also noted that lunar craters have only the most general resemblance to calderas (large volcanic craters) on Earth. Both lunar craters and calderas are large circular pits, but their structural details do not resemble each other in any way. In addition, Gilbert created small craters experimentally. He studied what happened when he dropped clay balls and shot bullets into clay and sand targets.

Gilbert was the first to recognize that the circular Mare Imbrium was the site of a gigantic impact. By examining photographs, Gilbert also determined which nearby craters formed before and after that event. For example, a crater that is partially covered by ejecta from the Imbrium impact formed before the impact. A crater within the mare formed after the impact.”

Relevance to Lunar Evolution

“Gilbert suggested that scientists could determine the relative age of surface features by studying the ejecta of the Imbrium impact. That suggestion was the key to unraveling the history of the Moon. Gilbert recognized that the Moon is a complex body that was built up by innumerable impacts over a long period.

In his book The Face of the Moon (1949), the American astronomer and physicist Ralph B. Baldwin further described lunar evolution. He noted the similarity in form between craters on the Moon and bomb craters created during World War II (1939–1945) and concluded that lunar craters form by impact.

Baldwin did not say that every lunar feature originated with an impact. He stated correctly that the maria are solidified flows of basalt lava, similar to flood lava plateaus on Earth. Finally, independently of Gilbert, he concluded that all circular maria are actually huge impact craters that later filled with lava.”

Conclusion

The Moon has been orbiting in space for a long time and has actually received many impacts. However by studying the lunar craters scientists have been able to gleam information about how the various layers of the Moon’s surface has formed.

End (63).

What People Thought About the Moon (62)

Introduction

The following excerpts from “Modern Mysteries of the Moon” by Vincent S. Foster show how the Moon was looked upon in the past by the people’s of the Earth. I find it quite interesting how the way we look at the Moon was changed over time, and there is still much to know.

Much Like Earth

“Some Greek philosophers believed that the Moon was a world much like Earth. In about A. D. 100, Plutarch even suggested that people lived on the Moon. The Greeks also apparently believed that the dark areas of the Moon were seas, while the bright regions were land.”

Moon and Sun Orbit the Earth

“In about A. D. 150 Ptolemy , a Greek astronomer who lived in Alexandria, Egypt, said that the Moon was Earth’s nearest neighbour in space. He thought that both the Moon and the Sun orbited Earth. Ptolemy’s views survived for more than 1300 years “

Correct View Moon Revolves with Earth Round the Sun

“But by the early 1500s, the Polish astronomer Nicolaus Copernicus had developed the correct view—Earth and the other planets revolve around the Sun , and the Moon orbits Earth.”

Galileo

“The Italian astronomer and physicist Galileo wrote the first scientific description of the Moon, based on his observations with a telescope. In 1609, Galileo described a rough, mountainous surface.

This description was quite different from what was commonly believed—that the Moon was smooth. Galileo noted that the light regions were rough and hilly and the dark regions were smoother plains. Galileo even sketched the Moon!”

End (62).

What Features Does the Moon Have? (61)

Introduction

The following excerpt is a good one I think because it addresses in quite succinct form what features the Moon actually has.

The following excerpt comes from the book “Moons of the Solar System (From Giant Ganymede to Dainty Dactyl)” by James A.Hall.

Excerpt

“Our moon is a big place. According what the IAU has recognized and named it has:

• 12 Vallis (valleys)

• 22 Maria (sea)

• Oceanus Procellarum (ocean)

• 20 Lacus (lakes)

• 3 Palus (marshes)

• 11 Sinus (bays)

• 30 Mons (mountains)

• 18 Montes (mountain ranges)

• Reiner Gamma (an albedo feature)

• 20 Catena (chains of craters)

• 18 Dorsa and 21 Dorsum (wrinkle-ridge system and wrinkle-ridges)

• 9 Promontorium (capes)

• 52 Rima and 53 Rimae (rilles (ridges) and rille systems)

• 8 Rupes (escarpments)

• 1609 known, named craters (older ones were erased and this does not include satellite craters, which do not have independent names.)

And when things the IAU does not recognize are added:

• 5 Ex-Seas

• 1 Unrecognized Marsh (Palus Nebularum)

• Private/personal identification systems”

Summary

The Moon certainly has many features similar to what the Earth has. Except that the number of craters I think is larger. This fact could have some weight in determining which origin theory of the Moon is more valid.

End (61).

Moon Origin – Giant Impact Theory (60)

Introduction

The following is a very concise description of the leading theory (note, only a theory at this stage) to describe the origin of the Moon. It is called the Giant Impact Theory.

The following excerpt comes from the book “Moons of the Solar System (From Giant Ganymede to Dainty Dactyl)” by James A.Hall.

Excerpt

“The leading theory of our moon’s formation is called the Giant Impact Theory. About 4.4–4.45 billion years ago (give or take a few millennia), a large body, a planetesimal often referred to as Theia, and thought to be about the size of Mars, smashed into Earth. This destroyed the crust of our planet, turning the whole planet to magma and a large ball of this material was jettisoned from the surface. This magma spun itself into a ball, attaining hydrostatic equilibrium, cooled, and solidified into Luna. It settled into an orbit near Earth, not fast enough to escape, nor so close as to crash into it, nor so slow as to decay considerably in the short-term. It is therefore in a somewhat stable if unusual orbit.”

Summary

This post was just to acquaint you with one of the more popular theories on the origin of the Moon. Note, it is still a theory, not

At this stage, the origin of the Moon has several theories, however, not one of them is without holes. The presence of observations that can not be explained by each theory (holes) make the search for the new theory ongoing.

End (60).

Moon and the Earth Compared (59)

Introduction

The following is a very concise piece of text comparing the Moon and the Earth.

The following excerpt comes from the book “Moons of the Solar System (From Giant Ganymede to Dainty Dactyl)” by James A.Hall.

Excerpt

“Most other major moons orbit along the equator of their planet. Our moon does not; rather it follows a margin along either side of the ecliptic, of about 5°.

It is also almost perfectly round. The moon’s roundness exceeds that of every planet (or at least every superior planet. Mercury is also very round.) Visually, it looks unusually flat. Most planets from our viewpoint are brighter near their center than at their limbs. It is also important to note that many other moons appear equally fuzzy at the edge from their own planets. Luna is different. The full moon is evenly lit at all parts, which was noticed by, and puzzled, the ancient Greeks.

Continuing onward, Earth and the Moon spin in similar orientations. Moon samples indicate the surface of the Moon was once liquid rock, or magma. The Moon is believed to have a relatively small iron core (but comparable to the Earth’s core by percentage of total mass and volume, accounting for density). Its density is lower than Earth’s own, but only slightly. Stable mineral isotopes of lunar and terrestrial rock are identical, implying a common origin.

Finally, until 2015, our moon was considered unique in having an electromagnetic field of its own. Recently Hyperion was found to have one as well, but much weaker than our moon, which has the strongest electromagnetic field found around a moon. In March of 2015 Ganymede was found to also have its own magnetic field.”

Summary

The Moon is almost perfectly round, and it appears in the night sky equally bright all over its face.

It has been found that the Moon has an iron core and even has a magnetic field (very weak).

As mentioned above in the excerpt the Moon does not orbit the Earth in line with the Earth’s equator, but at a 5.19° angle, which can be seen in the diagram above. The reason for this is not known and is certainly a very strange point, as other moons do not do this, they rather orbit their planet in line with their planet’s equator.

End (59).

Are All Moons Tidally Locked to their Planet? (58)

Introduction

I always thought that only our Moon and Earth were locked in a synchronised spin, accounting for why we always only see one face of the Moon. However after reading the passage below from the book “Moons of the Solar System (From Giant Ganymede to Dainty Dactyl)” by James A.Hall, I realised that this spin synchronisation is a feature common to many other moons.

Excerpt

“Luna is the proper name given to Earth’s own moon, hence the word Lunar. (These terms are used interchangeably in this chapter, and Appendix B only, as this rest of this book refers to other moons). Luna is tidally locked to the Earth so that one side always faces us, but due to a slight rocking motion called libration, we can actually see about 59 % of the total surface area of the moon (not all at once, of course). Many other moons exhibit tidal locking with their own planet. Still, the far side (often incorrectly referred to as the dark side, as it is spends as much time lit as the close side) remained mostly hidden until 1959. In 1959, the Soviet Luna 3 probe photographed this mysterious side”.

Summary

To have a synchronised spin between moon and planet seems to be a characteristic of the lunar principle.

So then we can extend this to esotericism and psychology. If we have lunar principles at work in a certain area, this principle of being locked or only seeing one side will be prevalent. Certainly this is observable in our psychology which esotericism states is essentially a lunar principled or based psychology. We typically only see one side of our psychology, we don’t perceive our psychology in a unified, uni-total way.

End (58).

How Many Moons are there in Our Solar System? (57)

Introduction

Here is an excerpt about the number of moons in our solar system. We certainly know that we have a moon or two and it is also known that some of the other planets in our solar system also have moons. This excerpt provides more exact and detailed information about this subject.

This excerpt has been taken from the book: “Moons of the Solar System (From Giant Ganymede to Dainty Dactyl)” by James A.Hall, published by Springer.

Excerpt

“The question of how many moons are in our Solar System has undergone a lot of flux. As an example, Venus has no conventional moons, but has a co-orbital body and two smaller bodies (asteroids) related to its orbit. And while no book could really detail these three objects, due to the small amount known about them, no book even mentions them in passing. Just like no book mentions that 4 of the 5000+ Jupiter Trojans are known to have moonlets, or that there must be 1000 or more that have moonlets that we are unaware of.

According to one source published in 1958 (a book which also clearly shows that Pluto is considerably larger than Mercury, almost the size of Mars), there were 31 moons in the Solar System (and since Pluto was bigger than Mercury, I think we can understand why it showed no moons around Pluto). A later source in 1963, which was revised in 1977, showed there were 34 moons. According to a 1993 book there were 61 for the giant planets, plus 3 for the Earth and Mars and 1 for Pluto (still a planet in 1993). Moving ahead to 2006, it was 163 (with pluses after Jupiter and Saturn), including little Dactyl (which orbits an asteroid), and minus 1 since Pluto was not a planet any more, but an ice dwarf planet/trans-Neptunian object, and Charon’s definition was fuzzy too. In 2011, it was 7 major, 8 medium, and 166 as a mix of minor and very minor (a four-part distinction which will be used extensively throughout the organization of the book.)

Now it is 2015, so it is time for a new count. When the book was completed, 164 moons could be found around planets, 8 around dwarf planets in the asteroid belt, 96 around smaller asteroids, 3 as Venus co-orbitals, with an additional 4 Jupiter Trojans, 51 Near-earth objects, 20 Mars-crossing objects, and 87 TNO satellites. There are also 150 or more “possible” satellites in Saturn’s rings (few of which are included in this volume due to minimal information about said objects). But be forewarned, this information changes practically on a day-to-day basis. However, through using Information Clearing House wikis, an exhaustive list of reputable sites can be found. One such list is an exhaustive list of asteroids with moon, and while it would not be practical to call the any such Earth-made list complete, it is exhaustive of what is currently known, even as that knowledge is continually being revised.”

Summary

So then the number is that there are 164 moons in total orbiting around planets. There are also many other moon-like objects, just as the second paragraph of the excerpt details orbiting around, dwarf planets (8), smaller asteroids etc.

End (57).

Impact of the Moon on Earth (56)

Change of Posting Style

Unfortunately due to a lack of time, I’m going to be changing my posting style. Instead of generating new and original content I am going to be posting some interesting excerpts from books on the Moon that I have come across.

Introduction

Here is an excerpt about the impact the Moon has had on the Earth. It has been taken from the book: “Moons of the Solar System (From Giant Ganymede to Dainty Dactyl)” by James A.Hall, published by Springer.

Excerpt

“Ever since humanity can recall, Luna has been in our sky by night and by day. For some it is a simple source of light, to others it is seen as a source of protection or inspiration and it causes superstition among others. Recent generations made it a goal to reach the surface. Regardless, for almost everyone, it holds a special place in our hearts and souls.

Light is one of the most obvious effects of the moon. During the day, the Earth has a seemingly unending source of light, the Sun. While the Sun does have a finite life span, few other than cosmologists concern themselves with such factors. For most it is enough that it exists now, and can be depended on until their dying day, as well as the dying day of the next 100 generations (which is considered long even in the astronomical timescale, though the cosmologists consider this rather shortsighted.) Light affects all functions through the circadian cycle which governs our day and night, various biological functions that slow down at night (like waste processing) which is based in part on light, and seasonal affective disorder is also based on day length/daylight length, and some treatments are based on light therapy. There are even people who study the effects of light on life; the terms scotobiologist and photobiologist have surfaced in recent years. The moon’s brightness is enough that in times before electricity it could aid in navigation, and it is still manipulated in the fishing techniques for certain fish. Even navigation would be impacted since the moon is one of the many objects which ship navigators have historically used to chart their path.

Beyond the practical, just listing the works of fiction about Luna, poetry and music about the moon, and people inspired by it would be a full-time job. If someone thinks the moon controls their life, they might look into this and discover the pseudo-science of astrology. Or they may use the older term for this belief and coin themselves a luna tic. The moon is astronomy for the everyman.

It may even have been a factor in the existence of life at all. A number of theories indicate there was a primordial soup on Earth. All reputable theories first evolve life in some sort of liquid medium. And the moon is certainly one of the primary factors of tides. Therefore the argument follows this short line: life requires tides; significant tides require the moon. Without the moon, tides would be much weaker (driven mostly by the sun) and with weaker tides and less mixing of this soup, life may never have arisen on Earth. Geodynamicists theorize that the ocean’s tidal flow, caused by the moon, may have made the climate more hospitable for speciation. Some molecular biologists even speculate that fast lunar tidal oscillation could have created an environment where protonucleic acid fragments might have benefited from the high salinity of the frequent low-tide periods. That cycle of rapidly forming and dissolving molecules in the rapidly rising and receding tidal waters could have eventually led to the development of DNA. This debate rages on.”

Summary

The Moon for sure has had an impact on the earth. The excerpt principally addresses the physical impacts the Moon has had on Earth, from fishing techniques, to navigation, to affecting our sleep patterns by the amount of extra light present at night, to literature, myth, legend to finally the role of the Moon in arising of life on the planet.

The interesting point about this excerpt is that in the last paragraph, there is some agreement there with esotericism, saying that life emerged from the waters and because the Moon heavily influences the waters the Moon has had a significant role in shaping life on this planet since its beginning. In esotericism the Moon is related to Life, fertility, conception and gestation.

End (56).