The Ellensburg, WA sky for the week of December 30, 2023

Saturday: At 6:00 p.m., Saturn is about two and a half fists held upright and at arm’s length above the southwestern horizon and Jupiter is five fists above the southeastern horizon.

Sunday: At 6:45 a.m., Mercury is less than a half a fist above the east-southeastern horizon. Venus, the brightest point of light in the sky, is one and a half fists above their southeastern horizon.

Monday: Today is the day we celebrate the anniversary of something new – a new classification of celestial objects. Giuseppe Piazzi discovered Ceres [pronounced sear’-ease], the first of what are now called “asteroids”, on January 1, 1801. Ceres is the largest asteroid in the belt between Mars and Jupiter. At first, Piazzi thought it was a star that didn’t show up on his charts. But, he noted its position changed with respect to the background stars from night to night. This indicated to him that it had to be orbiting the Sun. The International Astronomical Union promoted Ceres to the status of “dwarf planet” in August of 2006.

Tuesday: If the Sun looks big today and tomorrow, your eyes are not playing tricks on you. The Earth is at perihelion this evening. If you dig out your Greek language textbook, you’ll see that peri- means “in close proximity” and helios means “Sun”. So, perihelion is when an object is closest to the Sun in its orbit, about 1.5 million miles closer than its average distance of 93 million miles. Since it is winter in the Northern Hemisphere now, the seasonal temperature changes must not be caused by the Earth getting farther from and closer to the Sun. Otherwise, we’d have summer when the Earth is closest to the Sun. The seasons are caused by the angle of the sunlight hitting the Earth. In the winter, sunlight hits the Earth at a very low angle, an angle far from perpendicular or straight up and down. This means that a given “bundle” of sunlight is spread out over a large area and does not warm the surface as much as the same bundle in the summer. For the Northern Hemisphere, that very low angle occurs in December, January and February.

Wednesday: Late tonight and early morning’s weather forecast: showers. Meteor showers, that is. The Quadrantid meteor shower peaks late tonight and early tomorrow morning between midnight and dawn. Meteor showers are named after the constellation from which the meteors appear to originate. That makes this shower mysterious because there isn’t any constellation with this name now. The shower was named after Quadrans Muralis, an obsolete constellation found in some early 19th century star atlases. These meteors appear to come from a point in the modern constellation Draco the dragon. This point is about three fists above the northeastern horizon at 1:00 a.m. This year, the Moon will be rising around midnight so the dimmer meteors will be lost in the lunar light pollution. However, this is still one of the four major meteor showers with a sharp peak, meaning that you’re still guaranteed to see many more meteors than on a typical night if you are patient.

Meteors are tiny rocks that hit the Earth and burn up in the atmosphere. Most meteors are associated with the path of a comet. This shower consists of the debris from an asteroid discovered in 2003. Keeping with the comet-origin paradigm, astronomers think the asteroid is actually an “extinct” comet, a comet that lost all of its ice as it passed by the Sun during its many orbits. For more information about the Quadrantid meteor shower, go to http://earthsky.org/?p=155137.

Thursday: Now that you know meteors are rocks that burn up in the atmosphere, you will soon start to wonder what would happen if those rocks hit the surface of the Earth. Well, wonder no more. The browser-based app called Asteroid Launcher will simulate the collisions. You select the asteroid type, size, speed, and angle of impact. The most common impactor material is stone and the typical speed is 40,000 miles per hour, in case you want to introduce some realism into your simulation. Go to https://neal.fun/asteroid-launcher/, click on the map where you want the asteroid to land and then launch your virtual asteroid.

Friday: Has it been tough to wake up this past week? It should have been because the sunrise has been getting a little later since summer started. I know. I know. December 21 was the shortest day of the year. But, because the Earth’s orbit around the Sun is elliptical and not circular, the Earth does not travel at a constant speed. It moves faster when it is closer to the Sun and slower when it is farther away. This leads to the latest sunrise occurring in late December/early January and the earliest sunset occurring in early December. Neither of these happen on the first day of winter. On the first day of winter, however, the interval between sunrise and sunset is the shortest, making it the shortest day of the year. For more information, go to http://goo.gl/SJC5r.

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.

The Ellensburg, WA sky for the week of December 23, 2023

Saturday: Red is a popular Christmas color. It is also a popular star color. And R Leporis, also known as Hind’s Crimson Star, is one of the reddest stars in the sky. It is a star near the end of its life that has burned its helium nuclei into carbon. Convective currents, like those in a pot of boiling water, bring this carbon to the surface. There it forms a layer of soot that scatters away the light from the blue end of the visible spectrum leaving the light from the red end of the spectrum to reach our eyes. For more information about Hind’s Crimson Star and a list of other deep red stars, go to http://goo.gl/EnhRe4. Hind’s Crimson star is one fist to the lower right of Rigel, the brightest star in Orion. You’ll need binoculars or a small telescope to see Hind's Crimson star. But you can easily spot Rigel two and a half fists held upright and at arm’s length above the south-southeastern horizon at 10:00 p.m.

Sunday: Saturn is two and a half fists above the south-southwestern horizon at 6:00 p.m.

Monday: 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.

These three celestial objects are visible in the early evening sky tonight. At 6:00 p.m., Jupiter is nearly five fists above due southeast. Aries is right above Jupiter. The moon is two and a half fists above the north-northeastern horizon.

Tuesday: Did you get a new telescope 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.

Wednesday: Tonight’s December full moon is called the Cold Moon… for obvious reasons. On the evening of a full moon, the moon rises as the Sun sets, reaches its highest point in the sky in the south at midnight, and sets as the Sun rises.

Thursday: Venus is the bright point of light less than two fists above the southeastern horizon at 7:00 am. Challenge yourself to find Mercury less than a half a fist above the east-southeastern horizon at this time.

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.

The Ellensburg, WA sky for the week of December 16, 2023

Saturday: With the Sun as low as it gets in the Northern Hemisphere winter sky this week, you may wish it was a little more prominent. On September 27, NASA’s Parker Solar Probe had its closest encounter with the Sun, passing within 4.5 million miles. It passed 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 defined surface but there is a definite boundary between “cloud” and “not cloud”. For more about the mission plus short videos, go to http://parkersolarprobe.jhuapl.edu/.

Sunday: 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. 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 less than a half a fist to the right of the moon at 8:00 p.m. They are one and a half fists held upright and at arm’s length above the southwestern horizon. Jupiter is five fists above the southern horizon at this time.

Monday: 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 a very good 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.

Tuesday: Venus is two fists above the southeastern horizon at 7:00 a.m.

Wednesday: Vesta, the brightest asteroid, is in opposition tonight. That means tonight is the best night of the year to observe Vesta. You’ll need binoculars. First find Betelgeuse, four fists above due southeast at 10:00 p.m. Move the binoculars to the upper left about two binocular fields of view to a thin triangle. Vesta is in the middle of that triangle. Revisit that triangle for the next few nights. Vesta is the point of light than changes position from night to night.

Thursday: At 7:28 p.m., Pacific Standard Time, this evening, 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. But, the Sun 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.

At 8:00 p.m., Jupiter is a little to the left of the moon, midway up in the southern sky.

Friday: 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.

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.

The Ellensburg, WA sky for the week of December 9, 2023

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: 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.

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

Tuesday: Mercury is just above the southwestern horizon at 5:00 p.m. Saturn is three fists above due south and Jupiter is three fists above the east-southeastern horizon at this time

Wednesday:  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 below the horizon, leaving the sky dark enough for you 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.

Thursday: While the sky is getting darker earlier, 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: Venus is two fists above due southeast at 6:30 a.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.