Thursday, December 19, 2024

The Ellensburg, WA sky for the week of December 21, 2024

Saturday: At 1:20 a.m., Pacific Standard Time, the Sun reaches its lowest point in the sky with respect to the background stars. This point is called the Winter Solstice. During the day that the Sun reaches this point, your noontime shadow is longer than any other day of the year. Also, the Sun spends less time in the sky on the day of the Winter Solstice than any other making this the shortest day of the year. Even though it is the shortest day of the year, it is not the day with the latest sunrise or the earliest sunset. The latest sunrise is during the first week in January and the earliest sunset is during the second week in December. 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. However, the Sun's rise and set times depend on more than its apparent vertical motion. 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 first part of the analemma to go below the horizon. During the first week in January, it is on the last part of the analemma to rise above the horizon meaning that’s when we have the latest sunrises.

Sunday: Just before Christmas, you look for junk to clean out of your closets so you can re-gift it. I mean, so you can throw it out or recycle it. NASA’s Meter Class Autonomous Telescope on Ascension Island is a key tool in a program tracking about 22,000 pieces of space junk. Some of this junk is dangerous. The International Space Station occasionally performs debris avoidance maneuvers to keep its panels and sensitive instruments safe. For more information about the project, go to http://goo.gl/Kxgihd.

Monday: Venus is one and a half fists above the southwestern horizon and Saturn is three fists above the south-southwestern horizon at 6:00 p.m.

Tuesday: Mercury is one fist above the southeastern horizon at 7:00 a.m.

Wednesday: Where is the one who has been born King of the Jews? We saw Jupiter being eclipsed by the Moon in the east and have come to worship him” (Matthew 2:2, Bruce Palmquist version, informed by Michael Molnar). There are many theories as to the physical explanation of the Star of Bethlehem, the celestial object that guided the wise men to the location of Jesus. Some people think it was a recurring nova, a star that explodes. Some think it was a close alignment of bright planets. Some think it was a miracle that requires no physical explanation. In 1991, astronomer Michael Molnar bought an ancient Roman Empire coin that depicted a ram looking back at a star. Aries the ram was a symbol for Judea, the birthplace of Jesus. The Magi, or “wise men”, who visited the baby Jesus practiced astrology and would have been looking in that region of the sky for the king prophesied in the Old Testament. Molnar, a modern-day wise person, used sky simulation software to model the positions of planets and the Moon in the region of Aries. According to his model, Jupiter was eclipsed, or blocked, by the Moon on the morning of April 17, 6 BC. A book written by the astrologer of Constantine the Great in 334 AD supports Molnar’s theory. The book describes an eclipse of Jupiter in Aries and notes a man of divine nature born during this time. See https://goo.gl/o89A4o for more information.

Libra and Jupiter are visible in the early evening sky tonight. Aries is five fists above due southeast at 6:00 p.m. Jupiter is three fists above due east. The moon isn’t visible until tomorrow morning, one and a half fists above the southeastern horizon at 6:00 a.m.

Thursday: Did you get a telescope or binoculars for Christmas? The next item on your list should be a sky watching app for your phone. These apps will help you to get familiar with the constellations and bright stars. Then you can zoom into an area of interest and learn about objects that are visible through your telescope. I like SkySafari, a free app or low-cost iPhones app (depending on their promotions at the time). But there are many other good ones to choose from for little or no money. Go to https://www.lifewire.com/best-stargazing-apps-5086553 for seven short reviews. One of your first targets should be the Pleiades open star cluster. It is bright, easy to see with the naked eye and even more interesting in binoculars. It is six fists above due southeast at 8:00 p.m.

Friday: Aside from the Big Dipper, the northern sky doesn’t get enough love. Vega, the bright star in the constellation Lyra, is one fist above due northwest at 8:00 p.m.

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.

Thursday, December 12, 2024

The Ellensburg, WA sky for the week of December 14, 2024

Saturday: Jupiter is less than a fist held out at arm’s length to the right of the nearly full moon in the eastern sky at 7:00 p.m. They will stay in this same orientation throughout the evening and into the late-night sky.

Sunday: Are you disappointed because you are not going anywhere for the holidays? Why not take a (virtual) trip to outer space using Google’s new visualization tool called 100,000 Stars. It shows the stars in our neighborhood in an accurate 3-D simulation. The Sun is initially at the center. If you zoom in, you can click on neighboring stars and learn more about them. Go to http://stars.chromeexperiments.com/ for the simulation. It works best on a Chrome browser.

Monday: One of those stars in our neighborhood, the bright star Sirius, is one and a half fists above due southeast at 10:00 p.m.

Tuesday: Today is the start of the Saturnalia celebration, an ancient Roman festival in honor of their god Saturn, the god of agriculture and time. The holiday featured a break from work and school, a public banquet, and private gift giving. Some of these customs influenced the secular aspects of Christmas celebrations. For example, after Sheldon hugged Penny on The Big Bang Theory, Leonard proclaimed, “It’s a Saturnalia miracle” https://youtu.be/yarNJnZw2yk. It would not be a miracle if you saw the planet Saturn today. It is three fists above the south-southwestern horizon at 6:30 p.m. The very bright planet Venus is one fist above due southwest at this time.

Wednesday: Mars is right below the moon, three fists above due east at 10:00 p.m. As the hours go by, the moon will move slightly eastward compared to Mars, making it look like Mars is moving past it in the race from east to west. This is a great night to see how the moon appears to move slightly differently across the sky compared to planets.

Thursday:  With the Sun as low as it gets in the Northern Hemisphere winter sky this weekend, you may wish it was a little more prominent. Every orbit, NASA’s Parker Solar Probe has a close encounter with the Sun. Its last close encounter was in early October. Its next close encounter will be the closest one yet, passing just 3.8 million miles from the solar surface on Christmas Eve. It will pass through the boundary between outer space and the region where the Sun’s magnetic field has a tight hold on the plasma that makes up the outer layer of the Sun. Since the Sun does not have a solid surface, this is as close to touching the Sun as an object can get. It is analogous to “touching” a cloud. The cloud does not have a definite surface but there is a boundary between “cloud” and “not cloud”. For more about the mission plus short videos, go to http://parkersolarprobe.jhuapl.edu/.

Friday: Wow. The moon gets around. Now it is by the bright star Regulus at 10:00 p.m. Regulus is just to the right of the moon, one fist above the east-northeastern horizon. Like Mars and the moon on Wednesday, tonight you can see how the moon appears to move compared to planets. Spoiler alert: stars and planets appear to move very similar to each other compared to the moon’s apparent motion. This is because the moon is so much closer to the Earth than stars and even than relative neighbor planets such as Mars.

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.

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.