A shining band of angels suddenly broke through the crisp, night air over a band of Judean shepherds keeping watch over their flocks by night. "Glory to God in the Highest Heavens and peace to man on whom His favor rests," they sing in exalted harmony. Now I am sure that the shepherds gave nary a second thought to the phrase, the "Highest Heavens", and neither did I -- until this year. But this time on hearing it, it grabbed my attention. What exactly was meant by the Highest Heavens. You can go to your commentaries and research this and get some philosophical explanation. But what follows is a bit less philosophical and places a more scientific spin on the phrase. Be ready to be amazed by the worlds of the Cepheid Variable stars!
It was not that long ago that the astronomers of the world were totally unsure of how big a place the universe actually was. The one group thought that the universe was only as big as the Milky Way Galaxy, the galaxy that we call home. Others thought the universe stretched beyond to some greater distance, but no one could say for sure how far. So the battle raged between these camps. Existing telescopes and technology were insufficient to provide a convincing reconciliation to the question.
Then someone turned their attention to a certain category of stars that were seen to pulsate; not like "twinkle, twinkle little star," but having pulsations lasting days or weeks between the peaks of brightness. It turns out that the great predominance of stars are extremely stable over time and change little in size and brightness. For these normal stars, the crush of gravity bears down against the explosive force of their nuclear fusion reaction and keeps the ball of plasma contained as a stable, shining orb. But on rare occasions, stars will possess just the right amount of mass so that the exploding ball of gas can overcome gravity's crush, allowing the ball to grow in size. But as it grows, the fusion reaction decreases due to its greater volume and lower density. This lowers the explosive force inside and gravity starts to crush the ball again. But then the tight compression increases the fusion and the ball puffs out once more. And on and on it goes, creating a pulsing stellar mass; a Cepheid Variable star.
As one might imagine, these stellar anomalies are not difficult to spot and to study. They are very noticeable, like a lighthouse beacon on a rocky outcrop drawing the attention of the ship's pilots. But something else makes them an even more intriguing part of the Highest Heavens story. It has been determined that there is a relationship between the actual luminosity of these stars and their frequency of pulsation. Since it is a fairly simple matter to chart their pulsation period, it is therefore possible to know how bright these stars actually are. But the apparent brightness (how bright they appear to us from our observation point on earth) is decreased by the distance that the star is from the earth. So with this in mind, if we measure the period, we can determine the actual brightness. And then measuring the apparent brightness and comparing it with the actual brightness allows us to figure out the distance these Cepheid Variable stars are from earth! We finally have a "cosmic yardstick" that allows us to determine just how far these stars are from us.
And wonder of wonders -- these stars are often not even housed within our Milky Way galaxy! They are actually within galaxies that are far, far removed from us! The universe is actually much, much bigger than we had previously thought and populated with a multitude of galaxies as big as or bigger than the Milky Way. These stars have extended our understanding of how big the universe is to the same expansive understanding that the angels were sharing with the shepherds on that Judean hillside. The Cepheid Variables have shown us the Highest Heavens; realms that we have only recently been able to discover by scientific research. Which makes the end part of the angels greeting that much more significant. God -- who has made not just our own galaxy, but all of the millions of galaxies that exist beyond our own -- had sent this angel band from the Highest Heavens to share the Good News that His favor rested upon us. And all the Cepheid Variables pulsated with joy!
*** For more mind-blowing information on the wonders of God's heavens get the Great Courses Series called "The Life and Death of the Stars" by Keivan G. Stassan. This information is from lecture 17. ***
Well said Kenneth:) Jim S.
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