Thursday, February 13, 2025

The Ellensburg, WA sky for the week of February 15, 2025

Saturday: On February 18, 1930, Clyde Tombaugh discovered Pluto, at that time classified as the ninth planet. However, as astronomers started discovering a lot of similar objects in that part of the Solar System, they realized that they had a classification crisis on their hands. Should everything in this region of the Solar System be named a planet? Eventually the International Astronomical Union (IAU) reclassified Pluto and all future Pluto-like objects as dwarf planets. This week you can celebrate the discovery with the people at Lowell Observatory, the “home” of Pluto’s discovery. Go to https://iheartpluto.org/ for more information about online events this weekend.

Sunday: Venus is two and a half fists and Saturn is a half a fist above the west-southwestern horizon at 6:30 p.m. Does Venus look exceptionally bright tonight? It is at its brightest of the year.

Monday: This Presidents Day, let’s remember Abraham Lincoln: 16th president, country lawyer, man on the penny, wrestler, and astronomer. Astronomer? Well, maybe not an astronomer, but someone who used observational evidence from the sky to solve a problem. In 1858, Lincoln defended Duff Armstrong, a family friend who was accused of murder. The prosecution thought they had a strong case because their primary witnesses claimed to have observed the killing by the light of the nearly full moon, which they called “Moon bright”. Let’s listen in on the trial courtesy of the 1939 film, Young Mr. Lincoln.

Lincoln: How’d you see so well?

Witness: I told you it was Moon bright, Mr. Lincoln.

Lincoln: Moon bright.

Witness: Yes.

(Dramatic pause as Lincoln reaches for something)

Lincoln: Look at this. Go on, look at it. It’s the Farmer’s Almanack (sic). You see what it says about the Moon. That the Moon… set at 10: 21, 40 minutes before the killing took place. So you see it couldn’t have been Moon bright, could it?

Lincoln used the known information about Moon rising and setting times for August 29, 1858 as evidence in a trial. This is one of the earliest uses of forensic astronomy. For more information about Lincoln’s “almanac trial”, go to http://goo.gl/r83q4X.

Tuesday:  Are you going to skip a winter vacation because flights are too expensive? Then take a virtual vacation to a black hole. NASA scientists have just developed a visualization to show how light moves in the vicinity of a black hole. Book your ticket at https://www.nasa.gov/universe/nasa-visualization-shows-a-black-holes-warped-world/

 

Wednesday: It’s getting dark. The last remnant of twilight has disappeared. Suddenly, you notice a large softly radiant pyramid of light in the western sky. The base of this ghostly triangle is along the west horizon and the peak stretches two or three fists above the horizon. It is not really a ghost. It is an effect called the zodiacal light. This light comes from sunlight reflecting off dust grains in our solar system. The effect is the most visible when the band of constellations called the zodiac makes a steep angle with the horizon. You need a clear dark sky with no haze or light pollution to see the zodiacal light. At its brightest, the zodiacal light rivals the light of the central Milky Way. Look for the ghostly patch after twilight for the next few weeks.

Thursday: Two bright stars, Vega and Deneb, are hugging the northern horizon together at 11:00 p.m. Vega, the brighter of the two, is less than a half a fist above the north-northeastern horizon. Supergiant Deneb to two and a half fists to the left of Vega, closer to due north.

Friday: Jupiter is six fists above due southwest and Mars is six and a half fists above the southeastern horizon 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, February 6, 2025

The Ellensburg, WA sky for the week of February 8, 2025

Saturday: Venus is two and a half fists held upright and at arm's length above the west-southwestern horizon at 6:30 p.m. Saturn is right below it, about one fist above the horizon.

Sunday: Are you going to watch the super bowl tonight? Is the bowl really that super? After all, half the night the bowl is tipped upside down, spilling out all its contents. But don’t just focus on the functionality of the bowl. Think about how it inspires people across the world to look at the night sky. In Mongolia, participants in the super bowl are known as gods. An Arabian story says the super bowl is a coffin. I encourage you to go outside tonight at about 8:00 p.m., after whatever unimportant thing you have been doing since 3:30 p.m. Look low in the north-northwestern sky and watch the super bowl, also known as the Big Dipper, balancing on the end of its handle, proudly displaying its large bowl.

Monday: The Galileo spacecraft, launched in 1989 to explore the solar system, found evidence of life on a planet. Astronomers studied a highly pixelated image of the overall light emitted from the planet to detect the presence of oxygen. By analyzing the changes in pixel brightness as the planet rotated, astronomers got a rough idea of its surface characteristics. They determined that the planet has a mixture of both water and land, making it well suited for life. If you’d like to observe this planet tonight, just look down. The planet Galileo studied in this superficial way is called Earth. You might wonder why astronomers would gather such sparse data to study the Earth. The data Galileo gathered about Earth is the same as what Earth-based and Earth-orbiting telescopes can gather from objects in the outer solar system now and will be able to gather about planets orbiting other stars over the coming years. By gathering the data and comparing it to what we know about Earth, astronomers can catalog what data about other planets may indicate about those planets. For more information about this study, go to https://www.universetoday.com/165652/did-the-galileo-mission-find-life-on-earth/.

Tuesday: Jupiter is five and a half fists above due southwest at 9:00 p.m. Mars is six and a half fists above the southeastern horizon. It makes a small equilateral triangle with the stars Pollux and Castor.

Wednesday: The sky is so wondrous. It makes me want to sing. Who can forget that memorable song by Three Dog Constellations Night, “The sky is black. The stars are white. Together we learn to find the light.” Well, maybe it didn’t go like that. Which is good. Because not all stars are white. Most stars are too dim to notice a color. But two of the stars in the constellation Orion provide a noticeable contrast with each other. Betelgeuse, five fists above due south at 8:30 p.m. is a red giant. Rigel, the bright star about two fists to the lower right of Betelgeuse, is a blue giant.

By the way, the three dog constellations are Canis Major, the greater dog, found one and a half fists to the lower left of Orion; Canis Minor, the lesser dog, found two and a half fists to the left of Betelgeuse; and Canes Venatici, the hunting dogs, found low in the northeast sky, halfway between the Big Dipper and the horizon. Canis Major contains Sirius, the brightest star in the nighttime sky.

Thursday: The good news is the days are getting longer, and the nights are getting shorter. The better news for most readers of this column is the farther north you go in the United States, the longer the days get. Here in Ellensburg, there are almost two more hours of daylight than on the first day of winter. In the southern part of the US, there is only 50 more minutes of sunlight. If you’d like to have your own fun with day lengths and other time questions, go to https://www.timeanddate.com/sun/.

Friday: According to Greek mythology, the beautiful princess Andromeda was chained to a rock next to the ocean. Cetus the sea monster was about to devour her to punish her family. It seemed that all was lost. But along came the great warrior Perseus, fresh off his defeat of the evil Gorgon, Medusa. The only similarity between Andromeda and Medusa was that Andromeda caused people to stand still and stare at her beauty while Medusa turned people to stone because of her ugliness. (And you thought you looked bad in the morning.) Even though Perseus’ standing as the son of King Zeus and the slayer of Medusa was probably enough to win Andromeda under normal circumstances, Andromeda’s impending death-by-sea-monster was not a normal circumstance. So, Perseus drove his sword into the sea monster's neck and killed it. In a little-known addendum to the story, Perseus carved “Percy (heart symbol) Andi” in the rock, thus originating the use of the heart symbol as a substitute for the word “love”.

You can find these lovers in the sky this Valentine’s Day. Just remember it is rude to stare – because you never know who might turn to stone. First, find the Great Square of Pegasus at 7:00 p.m. between one and a half and three and a half fists above the west horizon. The lowest star in Andromeda is the top star in the square. This represents Andromeda’s head. Perseus is at her feet, nearly straight overhead. Mirphak, the brightest star in Perseus, is about eight fists above the west horizon. Perseus’ body is represented by the line of stars to the left and right of Mirphak.

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.