Skywatch for the week of January 18, 2021
Mon Jan 18,2021 HERSCHEL DISCOVERS URANIAN MOONS
On January 11, 1787 the astronomer William Herschel discovered Uranus' moons Titania and Oberon. Herschel was a self-taught astronomer and telescope maker; but his day job was as church organist in Bath, England. Herschel composed music, and was the first to conduct Handel’s oratorio, “Messiah,” in Bath. But like many educated people, he dabbled in other pursuits, and astronomy was his passion. He built his own telescopes, and was so good at it that colleagues were amazed to find that his handmade instruments were far superior to the ones commercially available at the time. It was with just such a telescope that he became the first person in history to discover another planet telescopically, in 1781. He suggested naming it George, after the king of England. But eventually it became known as Uranus. And six years later, his improved observations led to the discovery of its two largest moons.
Tue Jan 19. 2021 THE PLEIADES
Near the top of the sky this early evening, you’ll find a small, distinctive group of stars known as the Seven Sisters. Even with street lights shining, you can find them, although the serious light pollution problems we experience here reduces the Seven Sisters down to just two or three, or possibly they may look like a little smudge overhead. But if you can get away from the bright lights, you’ll see between six to eight stars here, arranged in a very tiny dipper shape. In Greek mythology, the Seven Sisters were the Pleiades, the daughters of Atlas, on whose shoulders the world rested. To the Seneca Indians, they were seven dancing sisters, who would not gather in food during the harvest, and so were carried in the arms of the West Wind, who placed them in the heavens where they became stars. But the Maya called these stars Itzab, the tail of the rattlesnake. Binoculars aimed at the Pleiades will reveal over a dozen stars, and astronomers have counted hundreds of stars in this open cluster.
Wed Jan 20, 2021 HERCULES’ WINTER ZODIAC
Many constellations chronicle the adventures of Hercules. To the north this winter evening are the stars of Cassiopeia, often depicted as a queen seated upon a throne; but the “w” pattern of stars here also suggests the upraised antlers of the golden hind, the capture of which was the third labor of Hercules. High in the west is Aries the Ram, a representation of the golden fleece, which Hercules pursued with his good friend Jason. High in the east sky is Taurus; this was a wild bull which Hercules subdued in a kind of a capture and release program. Above Taurus is Auriga the Charioteer, while to its east is the famous constellation Orion the Hunter, and these star patterns were sometimes seen as Eurytrion the herdsman and the giant Geryon, who kept the cattle that were the tenth labor of Hercules. And low in the southeast is the dog star Sirius, which represents the three-headed dog Cerberus, tamed by Hercules in his final labor.
Thu Jan 21, 2021 SMOKING STAR: THE ORION NEBULA
In the southeastern sky after sunset there are three stars close together in a row that form the belt of Orion the Hunter. Two stars above the belt mark Orion's shoulders, and two stars below the belt are his legs. Between Orion's belt and his legs there are a few faint stars which form the Hunter's sword. If skies are dark enough, you can see that the star near the bottom of the sword looks fuzzy - a little out-of-focus. To the Sik’si’ka or Blackfoot Indians of Montana, Alberta and Saskatchewan, this was "smoking star," and it represented a hero who saved his parents from injustice and rid the world of monsters. When you look at “smoking star” with binoculars, you will see it as a fuzzy object. Use a telescope with a little more magnification, and you can see the outlines of a large cloud, trillions of miles across. It is the Great Orion Nebula, which is lit up by bright stars within the cloud, which make it glow in the darkness of outer space.
Fri Jan 22, 2021 EDGAR ALLAN POE AND THE EVENING STAR
The American writer Edgar Allan Poe was born on January 18th in the year 1809. Most of us are familiar with his stories, such as, “The Tell-Tale Heart,” “The Raven,” and “The Pit and the Pendulum,” which have even been made into movies. But in 1848, the last big work that Poe wrote before his untimely death was something called, Eureka, in which he discussed astronomy and the universe. While Poe was no professional astronomer, he kept up with the latest discoveries and theories, and in Eureka he suggests that the Universe is expanding, which was confirmed over 70 years after his death. And in his poem, “Evening Star,” he compares the cold, heartless light of the moon to the warm light of Venus appearing in the western twilight (always makes me think of that bit of poetry at the end of the Moody Blues album, Knights in White Satin: “Cold hearted orb that rules the night…” This evening, you can compare Venus to the moon yourself: Venus is that brilliant “star” off to the west of the moon.