Earth Orbital Diagram
Earth Orbital Diagram
[An orbital map of the Earth is shown. The Sun is in the center, the Earth is at the right bottom, and the Moon is left below the Earth.] Why isn't there an eclipse every month? This is a common question! The answer is made clear by a quick look at the Earth's orbital diagram:
[Label Sun:] Solar plexus
[Label on the Earth's plane:] Sagittal plane
[Labels on Earth's orbit (beginning at the Earth counterclockwise):] Perihelix, Declension, Obsequity, Hypothecate, Enceliopsis, Equinox ( Solstice in British English)
[Two angles in the plane are labeled as:] Determinant of the date of Easter, Arctangent
[The plane of the Moon is pictured in a small angle to the Earth's plane and named Astral Plane. The angle is presented between two lines (Greek Nu or Gamma and a double Greek Chi) and identified by a character that looks similar to a Greek Phi but with two vertical lines.] [The labels at the Moon's path are:] Tropopause, Prolapse, Errata.
[An arrow points to the Earth at the zero meridian on the equator. The label reads:] Dimples of Venus

This comic is the third of five consecutive comics published in the week before and during the solar eclipse occurring on Monday, August 21, 2017 which was visible as a total solar eclipse within a band across the contiguous United States from west to east and visible as a partial eclipse across the entire contiguous United States and beyond. The other comics are 1876: Eclipse Searches , 1877: Eclipse Science , 1879: Eclipse Birds , and 1880: Eclipse Review .
The comic claims that the reason that eclipses don't happen every month is simple to understand by looking at an orbital diagram. Ironically, the cartoon has so many parts and labels that it is far more difficult to understand than is implied. While the graph itself is based on astronomical definitions , all the labels are nonsense in this context. In effect, the comic is a new take on a common joke in which a person asks a scientist a question, the scientist begins by saying "It's really quite simple", then proceeds to give a very lengthy and highly technical explanation that non-scientists would not be expected to understand. Diagrams for eclipses commonly include things that laypeople may not find relevant, without explanation, such as the umbra and penumbra.
All of the labels in the diagram are complicated words or phrases. Some are related to orbital mechanics (e.g. "equinox" and "perihelion"), while others are wholly unrelated or even made up.  Each label is nonsensical in its place in the diagram.  Compare/contrast with the standard Kepler Orbit diagram.
The title text references warnings to not look directly into the sun, but parodies those warnings by referring to 'orbit', the anatomical term for the eye socket.
All items are not drawn to scale. Neither the sizes of the celestial objects are that similar as shown nor the orbits are. The real scales are shown in this table:
When the distance Sun-Earth is scaled to one meter or below neither Moon nor Earth can be seen by the human eye.
Arctangent
Astral plane
Declension
Determinant of the date of Easter
Dimples of Venus
Enceliopsis
Equinox / Solstice
Equinox and Solstice have very different meanings:
Both types occur because the Earth's rotation axis is tilted (at 23.4 degrees) from its orbital plane (ecliptic) about the Sun.
Jokingly insisting that two different terms are American/British variants of the same word has been the topic of 1677: Contrails .
Hypothecate
Obsequity
Perihelix
Prolapse
Sagittal plane
Solar plexus
Tropopause
Angle between the Astral and the Sagittal Planes
Errata
If the plane of where the Earth orbits the Sun and where the Moon orbits the Earth were completely aligned, then there would be a solar eclipse at every new moon (once every 29.5 days ) and a lunar eclipse at every full moon (half a lunar period about 14.7 days after a New Moon).  However, the plane in which the Moon orbits the Earth is tilted with an inclination of 5 degrees relative to that of the ecliptic plane (the plane defined by the Earth's orbit around the Sun).  Eclipses are only possible during two eclipse seasons each year (half a year apart) where for a period of 31 to 37 days the Sun is nearly aligned with the two points in the tilted Earth-Moon plane where the Moon crosses the ecliptic plane.  During an eclipse season at the time of a new moon there will be solar eclipses visible from certain locations and during full moons there will be lunar eclipses.

The real explanation of eclipses is evident from this xkcd comic, but is labeled with a fictional character similar to a Greek phi but with two vertical lines; the remaining labels also do not contribute to this explanation and exist only to distract or misinform or entertain the reader. Thus, there is some truth behind the statement, "The answer is made clear by a quick look," assuming a quick look means only a glance at the diagram/drawing without taking the time to read the labels.
[An orbital map of the Earth is shown. The Sun is in the center, the Earth is at the right bottom, and the Moon is left below the Earth.] Why isn't there an eclipse every month? This is a common question! The answer is made clear by a quick look at the Earth's orbital diagram:
[Label Sun:] Solar plexus
[Label on the Earth's plane:] Sagittal plane
[Labels on Earth's orbit (beginning at the Earth counterclockwise):] Perihelix, Declension, Obsequity, Hypothecate, Enceliopsis, Equinox ( Solstice in British English)
[Two angles in the plane are labeled as:] Determinant of the date of Easter, Arctangent
[The plane of the Moon is pictured in a small angle to the Earth's plane and named Astral Plane. The angle is presented between two lines (Greek Nu or Gamma and a double Greek Chi) and identified by a character that looks similar to a Greek Phi but with two vertical lines.] [The labels at the Moon's path are:] Tropopause, Prolapse, Errata.
[An arrow points to the Earth at the zero meridian on the equator. The label reads:] Dimples of Venus
