Sunday, October 18, 2015

Supermoon Eclipses

Public attention is directed toward unusual and spectacular phenomena from the natural world by media accounts. The editorially injected “super” used in media descriptions generates added hype and sometimes well-deserved excitement. An example is “Superstorm Sandy,” the second most costly US hurricane which slammed into the east coast in October 2012.

Several weeks ago many world residents were alerted to a wondrous natural astronomical event not seen since 1982 and not to be observed again until 2033. A supermoon lunar eclipse would occur and would be visible to all earth residents able to view the moon during predicted hours on the evening of September 27. As a science teacher I looked forward to alerting my students to natural astronomical and meteorological wonders. In many years of teaching my subject matter received a welcome boost by comets, planetary conjunctions, eclipses, severe weather events, and other natural phenomena. These events provided natural motivation as we were temporarily relieved from our responsibility to supply classroom motivation on ordinary days.

We will now offer readers an abbreviated tutorial on this special eclipse after its occurrence: review supplements preview. Both “views” are necessary in good educational strategy.

In our solar system, motions of objects provide opportunities for one body to pass in front of another, obscuring the view of an observer. These out of the ordinary occasions add an extra dimension to already fascinating motions of solar system satellites—motions governed by physical laws. Ordinary physical laws of gravitation and motion, interesting as they may be to the science minded, are enhanced by the occurrence of unusual eclipses. A supermoon lunar eclipse? This is an example of what science instructors treasure to add mystique to their science education.

Before dealing with our recent supermoon eclipse, we remind readers that more ordinary lunar and solar eclipses occur frequently. In a lunar eclipse the earth casts its shadow on our neighboring moon. Normal sunlight is blocked from the moon. We see only a very dim, reddish lunar body during “ordinary” total lunar eclipses which occur 85 times during this century. There will be 230 lunar eclipses during the 21st century, but many of them will be partial or even less spectacular penumbral eclipses. In the 21st century there are also 224 solar eclipses, 68 of which are total with the remainder partial or in a special category termed “annular.”

The 2015 supermoon total lunar eclipse was part of a lunar tetrad: four consecutive total lunar eclipses occurring about six months apart. Tetrads occurs in groups every few hundred years. Eight tetrads occur this century but from 1600 to 1900, none occurred. 

This particular eclipse is a supermoon lunar eclipse because coincidentally, it occurs at perigee—when the moon is at the closest point to the earth in its orbit. The moon appears larger then because it is closer. The moon revolves around earth about once per month, so it is also at perigee (closest point to earth, about 226,000 miles away) about once per month, and at apogee (farthest point from earth, about 252,000 miles away) about once per month. The coincidence of the correspondence of a full moon lunar eclipse (sun, earth, and moon in line in that order) with the precise moment of perigee (moon closest to the earth) is rare indeed. If we add the coincidence of the September 27 eclipse occurring as the last of a tetrad of lunar eclipses, and also being this year’s harvest moon (the annual moon closest to the autumnal equinox) we have a series of rare and noteworthy coincidences.

We mentioned that the moon appears larger because it is at perigee. Its diameter is about 14% larger and consumes 30% more area in the sky. Consequently, it is also about 30% brighter than a more distant moon near apogee. On a comparison graphic this difference is startling on paper. The celestial view of the supermoon revealed a wonderfully large lunar orb. Our family spent several hours moon gazing with naked eye and binoculars that night in awe and wonder as we observed our special planet casting its shadow through space to our lunar companion.

If our readers wonder about the significance of the 2015 super moon in relation to Bible prophecy, we energetically dismiss any significance. The tetrad is of no prophetic significance. Tetrads have occurred for thousands of years. Many commentators have recently commented on “blood moons.” Blood moon is a dramatic description of the coppery tint present during total lunar eclipses but do not have prophetic significance. Total lunar eclipses have provided subtle colors during their occurrences for uncounted millennia of man’s sojourn on this planet.

Scriptural passages such as Joel 2:31 could have been applied to thousands of blood moons over the millennia. The term has been popularized lately by predictive utterances of mortal men. A history of failed human prophecies could fill many volumes. We should take note that future events are firmly in God’s hands. Connecting end times events with discernible astronomical events is not a gift bestowed on humans except in the general sense that future events will certainly occur and are known to God only, according to Acts 1:7 (NIV): “It is not for you to know the times or dates the Father has set by his own authority.”

As we conclude this post, we are reminded of a wonderful visual treat in the morning sky of October 2015. Planets Venus, Jupiter, Mars, and Mercury are all naked-eye visible in the eastern pre-dawn heavens. As I write on October 18, Jupiter and Mars are experiencing a spectacular conjunction, a mere one-half degree apart. We do not attribute this or any other unusual or awe-inspiring grouping to astrological or prophetic events. Rather, we give praise to the Creator who gives humanity the ability to visualize and recount past astronomical events and predict future ones within milliseconds of their occurrence according to the regularity and orderliness of God’s creation.