Skywatch for the week of October 31, 2022
Mon Oct 31, 2022 CREATURES OF THE NIGHT
If you’re out trick or treating tonight, and the skies are clear, you’ll be able to see some constellations that are suited for Halloween. The three stars in the summer triangle overhead, represent man-eating birds that were chased from the Stymphalian swamps by the hero Hercules. At sunset, the constellation of Scorpius the scorpion is sinking into the southwest. A scattering of stars in the southeast this evening mark the location of Cetus the Whale – a sea monster in Greek mythology. Perseus the hero, over in the northeast, holds out the snake-haired head of the gorgon Medusa, while Draco the dragon guards the northern skies tonight. And after midnight, Canis Major rises in the southeast. He is associated with the three-headed dog Cerberus who guarded the gates of the Underworld.
Tue Nov 1, 2022 CROSS QUARTER DAY
Today is the final cross-quarter day in our calendar. The quarter days mark each season’s beginning: March 21st for spring; June 21st for summer; September 21st for autumn; and December 21st for winter. The cross-quarter days divide each of these seasons in half: February 2nd, which is winter’s midpoint, called Imbolc by the ancient Celts; and in old calendars it was called Candlemas; not too long ago, it also picked up the name Groundhog’s Day. May 1st is the midpoint for spring, and was called Bealtane. August 1st, the middle of summer, was called Lunasadh or Lammas; and today, November 1st, is All Saints Day in the Church calendar, but also Samhain, the beginning of the ancient Druid year. Samhain is a late harvest occasion, when the last of the crops are brought in.
Wed Nov 2, 2022 HARLOW SHAPLEY
In the southwest this evening there is a concentration of globular star clusters which you can only see with a telescope. Each cluster contains thousands and thousands of stars packed in tight by gravity. Globular star clusters are all around us, but about half of them are gathered into one small spot in the sky, near the constellation Sagittarius. An astronomer named Harlow Shapley, born on November 2nd, in 1885, realized the significance of this clustering of clusters. In 1920 he suggested that because the globular clusters seemed to be centered around Sagittarius, that it was probable that that marked the center of the Milky Way galaxy. He was right – our solar system is part of the Milky Way, but we’re not in the middle of it, we’re a little over halfway out toward its edge.
Thu Nov 3, 2022 FRED WHIPPLE
Fred Whipple was born on November 5th, 1906. He helped to plot the orbit of the newly discovered planet Pluto, and in the 1930’s he showed that meteor showers are the result of particles shed from passing comets. Whipple is best known for his work in comet theory: in 1950, he came up with the model for comet composition that is still in use today. It’s the “dirty snowball” theory, which proposes that comets are big chunks of ice, mostly water ice, with some rocks and dust mixed in. When a comet nears the sun, the ices melt or sublimate and form an atmosphere or coma, around the comet nucleus; the solar wind and the pressure of sunlight blow this atmosphere out into a long tail. When the Giotto spacecraft flew by Halley’s Comet and looked at it during the comet’s 1986 appearance it confirmed his theory.
Fri Nov 4, 2022 MOON IN CONJUNCTION WITH JUPITER, PLANETARIUM SHOW
There are three planets that you can see in the sky this evening, and throughout the next couple of months. Tonight the waxing gibbous moon can be found next to the planet Jupiter, that bright, star-like object in the eastern sky after sunset. Saturn appears as a dimmer, yellow-tinted star in the south. The planet Mars shows up in the east in the late evening, but we’re about to pass it in a couple of months, so we’ve got a show called “Red Planet Rising,” that’s all about Mars, and you can come out and see that show tonight and tomorrow afternoon. After tonight’s shows the Treasure Coast Astronomical Society will provide guided telescopic views of the planets Jupiter and Saturn, weather permitting.