Thursday, December 5, 2024

The Ellensburg, WA sky for the week of December 7, 2024

Saturday: Imagine Opie and Andy Taylor walking down the dirt path at night to that fishing hole in the sky. They’d probably be looking to catch Pisces, the two fish already conveniently tied together with two ropes. The ropes are connected at the star Alrescha, Arabic for “the cord.” Alrescha is four and a half fists held upright and at arm’s length above due south at 8:30 p.m. The fish are attached to lines of stars that branch out at one o’clock and three o’clock from Alrescha. By the way, “The Fishing Hole,” The Andy Griffith Show’s theme song, was rated the 20th best TV theme song of all time by ign.com. That’s too low of a ranking in my opinion.

Sunday: Venus is a fist above the southwestern horizon and Saturn is three and a half fists above due south at 6:00 p.m.

Monday: The bright star Capella is nearly straight overhead at midnight.

Tuesday: The earliest sunset of the year in Ellensburg occurs today: 4:12 p.m. This seems odd because the shortest day of the year, the winter solstice, isn’t for about two more weeks. The Sun is at its southernmost point with respect to the background stars on the day of the winter solstice. This means the Sun spends the least amount of time above the horizon on that day. But the sunrise and sunset times depend on more than the Sun’s apparent southward motion in the sky. It also depends on where the Sun is on the analemma, that skinny figure-8 you see on globes and world maps. During the second week in December, the Sun is not quite to the bottom of the analemma. But it is on the leading edge of the analemma, the first section to go below the horizon. For a slightly better explanation of this, including a diagram, go to https://go.shr.lc/2NOMOQC. Or just go watch the sunset. But don’t stare at the Sun.

Wednesday: Jupiter is nearly six fists above the southeastern horizon and Mars is a little more than two fists above the eastern horizon at 10:00 a.m.

Thursday: While the days are getting shorter, the nighttime sky is actually getting brighter due to the greater use of low energy LED bulbs. While these bulbs use much less energy than incandescent or compact fluorescent bulbs, researchers think that people and communities are using more of the bulbs and leaving them on longer. This is increasing light pollution near cities. You can get more illumination on the subject at https://www.latimes.com/environment/light-pollution-latt-123.

Friday: The Geminid meteor shower peaks tonight and tomorrow morning. Meteor showers are named after the constellation from which the meteors appear to originate. These meteors appear to come from a point in Gemini the twins. This point is about four fists above due east at midnight tonight. You can follow this point throughout the night, as it will remain near the bright star Castor, the right-hand star of the “twin” stars Pollux and Castor. By 4:00 a.m., it is four fists above the southwest horizon. This shower is typically one of the best ones of the year producing bright, medium speed meteors with up to 80 meteors per hour under ideal conditions near the peak. This year, the moon will be near full, leaving the sky too light to see the dimmer meteors.

Most meteor showers occur when the Earth passes through the orbital trail of a comet. The broken off comet fragments collide with the Earth and burn up in the atmosphere. Astronomers had searched for a comet source for this shower since 1862 when the shower was first observed. Finally, in 1983, astronomers discovered the object that created the fragments that cause the meteor shower each year. To their surprise, it was a dark rock that looked like an asteroid, not a shiny icy comet. Astronomers named this object Asteroid 3200 Phaethon. For more information about the Geminid shower, go to https://goo.gl/f4qMqg.

The positional information in this column about stars and planets is typically accurate for the entire week. For up-to-date information about the night sky, go to https://nightsky.jpl.nasa.gov/planner.cfm. All times are Pacific Time unless noted.

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