by Theodore R Frimet
neither slumber nor sleep
The night sky is truly wonderful. I find it sometimes hard to explain. I have been searching for an explanation ever since. What, you ask? Orion the Hunter appears on his side, early evening at the horizon, and then stands tall, at the upper meridian later at night. That is the question.
I have observed, at Washington Crossing Park, as well as at Jenny Jump, that constellations appear larger or smaller, depending on the time of night. I’ve read this is due to an illusion. Perhaps the same type where we see a Large Moon, or a Small Moon. The moon size, however, depends on its relationship to our view thru the trees, or over the top of an apartment building, or house. It is in fact, an illusion.
I’d take it with a grain of salt, that the astronomers’ constellation view appears bigger or smaller. There are no trees in space. Apartment complexes and houses do not obstruct the wide field of view from the soccer field. I await the commentary of our readers to educate me and set the record straight.
For now, I will trust my eyes. The horizon at Washington Crossing Park is wonderful! Orion becomes my subject anew:
At the horizon’s far distance I spy the Hunter. He is virtually on his side. Hours later, I look up, and find him upright! I share my freshman opine with other seasoned amateurs. Of course they say, “happens all the time”. And yet, you and I must transcend Einstein, look past Newton, kick Galileo to the curb, and toss Kepler with Tycho Brahe in his pocket, too. Copernicus, shall we stare back at early cosmology of Ptolemy and Aristotle? Do I dare say, circles upon circles?
Oh, all right. Before I toss out the greats, and invoke the hostility of Astrology everywhere, I’ll remand myself to the Sixth Circle of Hell. Therein too heretics once burned before the eyes of Virgil and Dante.
In an all out effort to be brave, I crack open my toughest read ever recommended to me by another amateur. W. M. Smart’s Textbook on Spherical Astronomy, Sixth Edition, revised by R.M. Green, Cambridge University Press Edition, 1997, page 34, figure 17, to be precise. I’ll spare you the imagery, and make quick of the description, below:
The celestial equator is on a different visual angle than our horizon. And with the earth’s rotation, we observe not only the rise, and setting of Orion, we see his rotation as well. Further, our Southern observers “below” our equator see things a little differently. As we in the Northern Hemisphere witness The Great Hunter’s feet dipping below the line of site, our Southern partners would see Orion appear, feet first, and upside down!
Ah, the celestial sphere! A convenient construct that flattens out the three dimensions of space onto an imaginary plane. It is a brotherly view as if curved like the earth itself. Once again, it is we that are moved thru the night sky. From our observers fixed position on Earth, we rotate about our axis, giving the illusion that the hunter first sleeps, then awakens anew, standing upright.
This great heavenly envelope, or celestial sphere, is only a construct. There is no such thing. The motion of the heavenly bodies is an apparent one caused by Earths rotation. And with our axis tilt, as the stars follow the path of the celestial equator, Orion the Hunter neither sleeps, nor slumbers. Awake always, he remains my trusted friend thru the Winter night.