Skywatch for the week of March 23, 2020
Tue Mar 24, 2020 THE STARS OF THE PHARAOHS Of the Seven Wonders of the Ancient World, only the Great Pyramid of Khufu still stands. Like many old monuments, its four sides are aligned with the compass directions of North, South, East and West. Near the pyramid there is the statue of the Great Sphinx, a lion’s body with a woman’s face. It also faces toward the east, toward the rising sun. It is said that the sphinx represents the combined constellations of Leo the Lion and Virgo the Maiden. And the Great Pyramid, along with other pyramids nearby, align with the positions of the three stars in the belt of the Orion the Hunter, known to the Pharaohs as the mythical god Osiris. In ancient Egypt, the moon was called the left eye of Horus; his right eye was the sun. And three planets were identified with this son of Osiris. Mars was called Horus the Red; Jupiter was named Horus who Limits Two Lands; and Saturn was Horus the bull, not to be confused with the constellation Taurus the bull, to the east of Orion.
Wed MAR 25, SUN, SOLAR YEAR AND ECLIPTIC Watch the sun and you’ll discover it gets around. But of course you can’t watch the sun, because it’s too bright to look at without hurting your eyes. If you could somehow dim down the sun enough, you could also see the stars in the sky at the same time. (Actually, there are times when this happens – during total solar eclipses.)Assuming you could see the sun and stars at the same time, you’d notice the sun drifts eastward like the moon, although not as fast as the moon. The moon moves 13 degrees a day; the sun only moves about 1 degree a day. After 365 days, the sun would return to conjunction with the star it had been beside exactly a year ago. A solar year, then is the amount of time it takes the sun to go once around the heavens, and the invisible line that traces out that path is called the ecliptic. The constellations through which the sun passes each year is called the zodiac, and the ecliptic is its central line.
Thu Mar 26, 2020 ROBERT FROST Robert Frost was born on March 26th, 1874. In his poem, "The Star Splitter." Frost relates the tale of a man who bought a telescope, saying "The best thing that we're put here for's to see; The strongest thing that's given us to see with's A telescope. Often he bid me - come and have a look - Up the brass barrel, velvet black inside, At a star quaking in the other end. That telescope was christened the Star-Splitter, Because it didn't do a thing but split A star in two or three...” Frost was referring to the telescope’s ability to resolve detail, and reveal fainter stars not visible to the human eye alone. In another poem, Frost describes the constellation Canis Major, the “great Overdog That heavenly beast With a star in one eye Gives a leap in the east. He dances upright All the way to the west And never once drops On his forefeet to rest.” Because of the earth’s rotation, Canis Major does move across the sky just the way Frost describes it.
Fri Mar 27,2020 DARKNESS WASTING TIME By now most of us have recovered from the semiannual trauma of converting from Standard Time to Daylight saving Time. We’ve run our clocks ahead an hour to compensate for the extra daylight we get early in the morning, thanks to the longer path our sun travels through the sky as we approach summer. This may be a great idea for most folks, but to astronomers who now have to wait an extra hour for the sun to set, this shift is known as darkness wasting time. There has been some talk lately of either abolishing daylight saving time, or abolishing standard time. An article in the Washington Post favored getting rid of Standard Time altogether. That was actually tried back in January 1974; but the extended early morning darkness resulted in a 17% increase in early morning traffic fatalities - so we went back to Standard Time.