Cosmos/Moon/Eclipses

Lunar Eclipses

NASA's view on Lunar Eclipses

A lunar eclipse occurs when the Sun, Earth, and Moon align so that the Moon passes into Earth’s shadow. The Moon becomes darker and may even turn red.

Lunar eclipses occur at the full moon phase. When Earth is positioned precisely between the Moon and Sun, Earth’s shadow falls upon the surface of the Moon, dimming it and sometimes turning the lunar surface a striking red over the course of a few hours. Each lunar eclipse is visible from half of Earth.

According to NASA, there are three different types of lunar eclipses:

1. Total lunar eclipse
The Moon moves into the inner part of Earth’s shadow, or the umbra. Some of the sunlight passing through Earth’s atmosphere reaches the Moon’s surface, lighting it dimly. Colors with shorter wavelengths ― the blues and violets ― scatter more easily than colors with longer wavelengths, like red and orange. Because these longer wavelengths make it through Earth’s atmosphere, and the shorter wavelengths have scattered away, the Moon appears orangish or reddish during a lunar eclipse. The more dust or clouds in Earth’s atmosphere during the eclipse, the redder the Moon appears. Moon is partially in shadow

2. Partial lunar eclipse
An imperfect alignment of Sun, Earth and Moon results in the Moon passing through only part of Earth's umbra. The shadow grows and then recedes without ever entirely covering the Moon. Full moon

3. Penumbral eclipse
If you don’t know this one is happening, you might miss it. The Moon travels through Earth’s penumbra, or the faint outer part of its shadow. The Moon dims so slightly that it can be difficult to notice.

4? Selenelion Eclipse - 😑🤷‍♀️ NASA forgot to mention this one.
A selenelion eclipse occurs when the Moon rises fully eclipsed at sunset (in the evening, in the east) or sets fully eclipsed at sunrise (in the morning, in the west).

Wait! What? The moon and the sun are both visible in the sky! How can that be? NASA says the Moon is eclipsed only when it moves into Earth’s shadow in space. Which is why this type of eclipse is often forgotten and the only eclipse to be labeled a "phenomenon". It is said to occur because of the curvature of Earth and our planet’s atmosphere refracts the images of the Sun and Moon and makes them appear to be in slightly different positions.

The same "phenomenon" that makes our sky blue and our sunsets red causes the Moon to turn red during a lunar eclipse. It’s called Rayleigh scattering. Light travels in waves, and different colors of light have different physical properties. Blue light has a shorter wavelength and is scattered more easily by particles in Earth’s atmosphere than red light, which has a longer wavelength.

NASA's explanation of the Red moon during lunar eclipse

Red light, on the other hand, travels more directly through the atmosphere. When the Sun is overhead, we see blue light throughout the sky. But when the Sun is setting, sunlight must pass through more atmosphere and travel farther before reaching our eyes. The blue light from the Sun scatters away, and longer-wavelength red, orange, and yellow light pass through.

It is said that during a lunar eclipse, the Moon turns red because the only sunlight reaching the Moon passes through Earth’s atmosphere. The more dust or clouds in Earth’s atmosphere during the eclipse, the redder the Moon will appear.

Saros Cycle

The Saros Cycle can be used to predict eclipses of the Sun and Moon. The earliest discovered historical record of what is known as the saros is by Chaldean (neo-Babylonian) astronomers in the last several centuries BC. It was later known to Hipparchus, Pliny and Ptolemy.

Every 18 years and 11 days an eclipse occurs at roughly the same position in the zodiac, or to be more precise: 10 1/2 degrees further on (an eclipse occurs when either a new or full moon occurs close to the moon's nodal axis). This is a saros period.

A saros cycle of Solar Eclipses encompasses 70 solar eclipses over a period of 1200 to 1400 years. A saros cycle of Lunar Eclipses encompasses around 45 lunar eclipses over a period of around 800 years.

A series of eclipses that are separated by one saros is called a saros series. It corresponds to:

• 6,585.321347 solar days
• 18.029 years
• 223 synodic months
• 241.999 draconic months
• 18.999 eclipse years (38 eclipse seasons)
• 238.992 anomalistic months
• 241.029 sidereal months

The saros cycle is useful for predicting the times at which nearly identical eclipses will occur.

Cause of Lunar eclipses according to Zetetic Astronomy

In Chapter 11: "CAUSE OF SOLAR AND LUNAR ECLIPSES"
We have seen that, during a lunar eclipse, the moon's self-luminous surface is covered by a semi-transparent something; that this "something" is a definite mass, because it has a distinct and circular outline, as seen during its first and last contact with the moon. As a solar eclipse occurs from the moon passing before the sun, so, from the evidence above collected, it is evident that a lunar eclipse arises from a similar cause--a body semi-transparent and well-defined passing before the moon; or between the moon's surface and the observer on the surface of the earth.

That many such bodies exist in the firmament is almost a matter of certainty; and that one such as that which eclipses the moon exists at no great distance above the earth's surface, is a matter admitted by many of the leading astronomers of the day. In the report of the council of the Royal Astronomical Society, for June 1850, it is said:--

"We may well doubt whether that body which we call the moon is the only satellite of the earth."

In the report of the Academy of Sciences for October 12th, 1846, and again for August, 1847, the director of one of the French observatories gives a number of observations and calculations which have led him to conclude that,--

"There is at least one non-luminous body of considerable magnitude which is attached as a satellite to this earth."

Sir John Herschel (English polymath, mathematician, astronomer, chemist, inventor and photographer; 1792 – 1871) admits that:--

"Invisible moons exist in the firmament."

Sir John Lubbock (banker, Liberal politician, philanthropist, scientist and polymath; 1834 – 1913) is of the same opinion, and gives rules and formula for calculating their distances, periods. At the meeting of the British Association for the Advancement of Science, in 1850, the president stated that,---

"The opinion was gaining ground, that many of the fixed stars were accompanied by companions emitting no light."

"The 'changeable stars' which disappear for a time, or are eclipsed, have been supposed to have very large opaque bodies revolving about or near to them, so as to obscure them when they come in conjunction with us."

"Friedrich Bessel ( astronomer, mathematician, physicist, and geodesist; 1784 - 1846), the greatest astronomer of our time, in a letter to myself, in July 1844, said, 'I do indeed continue in the belief that Procyon and Sirius are both true double stars, each consisting of one visible, and one invisible star.' . . A laborious inquiry just completed by Peters at Königsberg; and a similar one by Schubert, the calculator employed on the North American Nautical Almanack, support Bessel."

Origen Adamantius (early Christian scholar, ascetic, and theologian; 185 AD):

"The belief in the existence of non-luminous stars was prevalent in Grecian antiquity, and especially in the early times of Christianity. It was assumed that 'among the fiery stars which are nourished by vapours, there move other earthy bodies, which remain invisible to us!'"

Diogenes of Appollonica (ancient Greek philosopher; 5th century BCE):

"Stars that are invisible and consequently have no name move in space together with those that are visible."

Lambert in his cosmological letters admits the existence of "dark cosmical bodies of great size."

We have now seen that the existence of dark bodies revolving about the luminous objects in the firmament has been admitted by practical observers from the earliest ages; and that in our own day such a mass of evidence has accumulated on the subject, that astronomers are compelled to admit that not only dark bodies which occasionally obscure the luminous stars when in conjunction, but that cosmical bodies of large size exist, and that "one at least is attached as a satellite to this earth." It is this dark or "non-luminous satellite," which when in conjunction, or in a line with the moon and an observer on earth, IS THE IMMEDIATE CAUSE OF A LUNAR ECLIPSE.

Those who are unacquainted with the methods of calculating eclipses and other phenomena, are prone to look upon the correctness of such calculations as powerful arguments in favor of the doctrine of the earth's rotundity and the Newtonian philosophy, generally. One of the most pitiful manifestations of ignorance of the true nature of theoretical astronomy is the ardent inquiry so often made, "How is it possible for that system to be false, which enables its professors to calculate to a second of time both solar and lunar eclipses for hundreds of years to come?" The supposition that such calculations are an essential part of the Newtonian or any other theory is entirely gratuitous, and exceedingly fallacious and misleading. Whatever theory is adopted, or if all theories are discarded, the same calculations can be made. The tables of the moon's relative positions for any fraction of time are purely practical--the result of long-continued observations, and may or may not be connected with hypothesis. The necessary data being tabulated, may be mixed up with any, even the most opposite doctrines, or kept distinct from every theory or system, just as the operator may determine.

Anaximenes' Astronomy

Two opaque (avin) dark faces (or bodies) move and revolve far below the sun and the moon. When in the usual revolution of the sky, they pass below the sun or below the moon, it (i.e., one of the two opaque bodies) becomes a covering and stands as a curtain over the sun. Thus it is that the sun or the moon is not seen. Of both the seen opaque bodies, one is called the head and the other the tail. Their motion is explained in the calculation of astronomers.

However, in standing in the way of, and in covering those luminaries, they do not thereby (actually) raise a covering over those luminaries. From (the fact of) the luminaries being in a place pure and free from opposition, and from (the fact of) the (two) concealers (of light) being far below them, there result no diminution of light in those luminaries, except this, that their light is concealed from the world, and that their all-adorning energy of supplying light to the earth during that time is incomplete.

Ancient Beliefs

A FEW ANCIENT BELIEFS ABOUT THE ECLIPSE
Ancient Aryans
The ancient Aryans, and the different nations that descended from them, held a belief, that the eclipse was the result of a fight between a hostile power and the Sun or Moon as the eclipse happened to be solar or lunar.

Ancient Hindus
"Rahu is a Daitya who is supposed to seize the sun and moon and swallow them, thus obscuring their rays and causing eclipses. He had four arms, and his lower part ended in a tail. He was a great mischief-maker. The sun and moon detected him and informed Vishnu, who cut off his head and two of his arms, but, as he had secured immortality, his body was placed in the stellar sphere, the upper parts, represented by a dragon's head, being the ascending node, and the lower parts, represented by a dragon's tail, being Ketu the descending node. Rahu wreaks his vengeance on the sun and moon by occasionally swallowing them."

The same story is referred to in the Vishnu Purana. Thus, it is the fight between the Daitya Rahu and the sun or moon that causes the solar or the lunar eclipse.

The Mongols
The Mongols have taken this belief from the Indians with this difference, that among them Aracho has taken the place of Rahu. The Scandinavians say that there are two wolves (Sköll and Hati) which always run after the sun and the moon. Hati, which is also known by the name of Mànagarmr (the dog of the moon), will, in the end, devour the moon. It is this tradition that has given rise to the Burgudian phrase "May God save the moon from the wolves,' which is used ironically for a distant danger.

Ancient Greeks
The ancient Greeks, at one time believed, that Diana or the moon once fell in love with Endymion, the beautiful shepherd when he once slept unclothed, on Mount Latmos, and that the lunar eclipses were due to her absence from the Heavens to pay her frequent nocturnal visits to her lover on the earth.

The Romans
The Romans believed that the sorcerers and magicians, especially those of The Thessally, had the power to bring the moon down to the earth from the heaven to aid them in their enchantments and that the eclipse was due to this attempt on the part of the magicians.

The Chinese
The Chinese belief about the "eclipse is thus described by a French Jesuit named Lewis Le Comte / Louis-Daniel Lecomte (1655–1728):

Nations have ever been astonished at eclipses, because they could not discover the cause of them; there is nothing so extravagant as the several reasons some have given for it; but one would wonder that the Chinese, who as to astronomy may justly claim seniority over all the world besides, have reasoned as absurdly on that point as the rest. They have fancied that in heaven there is a prodigious great dragon, who is a professed enemy to the sun and moon, and ready at all times to eat them up. For this reason, as soon as they perceive an eclipse, they all make a terrible rattling with drums and brass kettles, till the monster frightened at the noise lets go his prey.

See Also

• rumble: The problem with the August 2017 solar eclipse and the globe

Further Reading

• https://eclipse.gsfc.nasa.gov/SEsaros/SEpanorama.html
• Book: 1887 Canon der Finsternisse (Canon of Eclipses)