The Ellensburg, WA sky for the week of September 27, 2025

Saturday: Mars is right above the west-southwestern horizon at 7:30 p.m. Antares, which means “rival of Mars", is less than a half a fist to the right of the moon, low in the south-southwestern sky.

Sunday: You learned about Cassiopeia last week. Over 200 years ago, the astronomer Caroline Herschel discovered an open star cluster that looks like a rose. This cluster, called Caroline’s Rose, is about 6,500 light years away and consists of about 1,000 stars that are one third the age of the Sun. Through binoculars, it looks like a fuzzy patch. At 10:00 p.m., find the star at the top of the sideways “W” known as Cassiopeia. It is six fists held upright and at arm’s length above due northeast. When that star is in the lower left portion of your field of view, Caroline’s Rose is in the center to upper right. For more information about Caroline’s Rose, go to https://stardate.org/radio/program/2020-09-09.

Monday: Saturn is three fists above due southeast at 10:00 p.m.

Tuesday: Since Halloween is a month away, the stores are filled with bags of candy clusters. Use this reminder to take time to look at a star cluster. The Hyades cluster is an open star cluster that represents the V-shaped face of Taurus the bull. It is one of the biggest and nearest star clusters with about 200 stars 150 light years away. The Hyades cluster was the first cluster to be the subject of detailed motion studies. These studies allowed astronomers to pinpoint the distance to the Hyades and provide important information about the scale of the universe. Aldebaran, about one fist above the east-northeastern horizon at 11:00 p.m., is a foreground star and not a part of the Hyades cluster.

Wednesday: Need a caffeine pick-me-up? Make it a double. Need an astronomy pick-me-up? Make it a double double. Find the bright bluish star Vega, in the constellation Lyra the lyre, five and a half fists above due west at 10:00 p.m. Less than half a fist above Vega is the “star” Epsilon Lyra. If you look at Epsilon Lyra through binoculars, it looks like two stars. If you look at Epsilon Lyra through a large enough telescope, you will notice that each star in the pair is itself a pair of stars. Each star in the double is double. Hence, Epsilon Lyra is known as the double double. The stars in each pair orbit a point approximately in the center of each respective pair. The pairs themselves orbit a point between the two pairs.

Thursday: At 6:00 a.m., Venus is one fist above due east and Jupiter is five and a half fists above the southeastern horizon.

Friday: In 1987, the rock group Def Leppard sang “Pour some sugar on me, in the name of love. Pour some sugar on me, come on, fire me up”. In 2012, some European astronomers “found some sugar near stars, they were very young. Found some sugar near stars, out where planets formed.” Astronomers observed molecules of glycolaldehyde, a simple form of sugar, in the disk of gas and dust orbiting young binary stars. This is the first time astronomers have found this simple sugar so close to a star indicating that organic molecules can be found in planet-forming regions of stars. For more information, go to http://goo.gl/tfwy1.

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.

The Ellensburg, WA sky for the week of September 20, 2025

Saturday: Saturn is in opposition tonight. That doesn’t mean that Saturn is stubborn. Opposition means that Saturn is on the opposite side of the Earth as the Sun. When an object is in opposition, it is at its highest point in the sky during the darkest time of the day. Thus, opposition is typically the best time to observe a planet. Saturn is about three and a half fists held upright and at arm’s length above due south at 1:00 a.m. It is nearly two fists above due southeast at 10:00 p.m. Careful readers of this column may recall that Saturn is in opposition about 12 days later each year: July 21, 2020, August 1, 2021, August 14, 2022, August 26, 2023, and September 7, 2024. An outer planet is in opposition when Earth passes it up as both orbit the Sun. The farther out a planet is, the less it has moved along its orbit, and the closer it is to exactly one year from one Earth passing to the next. For comparison, it is about 18 months between successive oppositions for Mars. Saturn is three fists above due southeast at 10:30 p.m. tonight.

Sunday: Tonight’s moon phase is new. Typically, that is pretty boring. Tonight, in the South Pacific and New Zealand it will be pretty exciting because there will be a partial solar eclipse visible from there. For more information so share with your New Zealand friends, go to https://www.timeanddate.com/eclipse/solar/2025-september-21

Monday: At 10:30 a.m. PDT, the center of the Sun crosses the celestial equator and passes into the southern sky. The celestial equator is an imaginary line that divides the sky into a northern and southern half. When the Sun is in the southern half of the sky, it appears to take a shorter path from rising to setting. It also does not get as high in the sky at noon. This leads to shorter days and longer nights. Since the Sun crosses the celestial equator today, there is an instant when it is equally in the northern and southern sky, called the north and south celestial hemispheres. This so-called “equal night” is given by the Latin word equinox. Thus, today is known as the Autumnal Equinox. However, the day and night are not of equal duration today. The sun rises at 6:49 a.m. and sets at 6:58 p.m. in the northern latitudes of the United States.

Tuesday: Mars is right above the west-southwestern horizon at 7:30 p.m.

Wednesday: To the people of Ancient Greece, the stars that are about five and a half fists above the northeastern and eastern horizons, respectively, at 10:30 p.m. were known as Cassiopeia and Andromeda, a mythological queen and her daughter. But not all cultures imagined the same pictures in the sky. To the people of Polynesia, the stars of Cassiopeia and Andromeda represented a dolphin, called Kwu. Cassiopeia formed its tail, the brightest stars of Andromeda formed its fins, and its fainter stars outlined the dolphin’s body.

Thursday: Ask someone which day in September has the same duration day and night. Go ahead, ask someone. Why are you still reading this? I can wait. If that person says the first day of autumn, they are wrong. Today, three days after the first day of autumn, is the date on which day and night are closest in duration. There are two main reasons for this. First, the atmosphere acts like a lens, bending light from the Sun above the horizon when the Sun is actually below the horizon. This makes the Sun appear to rise before it actually rises and appear to set after it actually sets. Second, fall starts when the center of the Sun passes through the point called the autumnal equinox. But the Sun is not a point. The upper edge of the Sun rises about a minute before the center of the Sun and the lower edge sets a minute after the center of the Sun. Thus, even if we didn’t have an atmosphere that bends the sunlight, daytime on the first day of autumn would still be longer than 12 hours.

Friday: At 6:00 a.m., Venus is a little more than a fist above due east. At this time, Jupiter is five fists above the southeastern horizon.

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.

The Ellensburg, WA sky for the week of September 13, 2025

Saturday: Mars and Spica are just above the west-southwestern horizon at 8:00 p.m.

Sunday: While many people think they need a telescope to enjoy looking at the night sky, some objects actually look better through binoculars. Open star clusters are one of those types of objects. M39, the 39th object in Charles Messier’s catalog, is straight overhead at 11:00 p.m. This open star cluster contains about 30 stars in a region about seven light years across and a thousand light years away. A quick trigonometry calculation shows that the cluster is about the same size as the full moon in the night sky. Read more about M39 at https://stardate.org/radio/program/2022-09-04.

Monday: Saturn is one and a half fists above the east-southeastern horizon at 9:00 p.m.

Tuesday: “There’s water in them thar craters,” frozen water, which is. There has been speculation since the 1960s and indirect evidence since the 2000s of water on the Moon. Three years ago, astronomers studied data from four earlier missions. They noticed that the light reflecting off the bottom of craters near the lunar South Pole showed characteristics of light reflecting off pure ice. The water likely came from comet impacts or other solar system objects with trace amounts of water ice. Last summer, the Indian Space Research Organization became the fourth country to successfully land on the moon when Chandrayaan-3 landed near the lunar South Pole to study the water there. Read more about it at https://www.space.com/chandrayaan-3-moon-south-pole-why-nasa-wants-to-go-too. The moon is five fists above the eastern horizon at 6:00 a.m. Jupiter is less than a half fist to the lower right of the moon.

This will be a good day to try to see a planet during the day. Wait until the sun rises. Next, find the moon with your naked eye. Then aim your binoculars at the moon. Look for Jupiter below the moon. Finally, move away the binoculars and look at that same spot with your naked eye.

Wednesday: Fomalhaut, the farthest south of all the bright stars visible in the northern United States, is one fist above the south-southeastern horizon at 10:30 p.m.

Thursday:  Mnemonics are helpful for remembering astronomy facts. (Similarly, “Johnny Mnemonic,” the 1995 cyberpunk film, was helpful in getting Keanu Reeves’ career going.) After all, school children around the world are learning the order of the planets by remembering, “My very excellent mother just served us nine….” Oops, I guess that one needs updating with Pluto being classified as a dwarf planet. Well, here’s one that will not need updating for tens of thousands of years: the order of the stars in the Big Dipper. Because the nighttime stars are so far away from us, their actual motion through the sky, called their “proper motion” is not noticeable over even thousands of years. That is why the constellations have remained the same since ancient times. But two stars in the Big Dipper have a proper motion large enough such that in 100,000 years; the stars will no longer make a dipper shape. You can see this simulation at the American Museum of Natural History video found at https://youtu.be/sBfUBtdo8yo. Until then, you can remember the names of the seven dipper stars in order from handle to cup by remembering this helpful advice for teens: “AM, ask mom. PM, dad.” The stars are Alkaid, Mizar, Alioth, Megrez, Phad, Merek, and Duhbe. The Big Dipper is one fist above the northern horizon at midnight.

Friday: The moon, Venus, and the star Regulus form a tight cluster one and a half fists above due east at 6:00 a.m. Venus is about 100 times the brightness of Regulus. Both are to the upper right of the moon.

Today is an even better day to see a planet during the day. Wait until the sun rises. Next, find the moon with your naked eye. Then aim your binoculars at the moon. Look for Venus above the moon. Finally, move away the binoculars and look at that same spot with your naked eye.

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.

The Ellensburg, WA sky for the week of September 6, 2025

Saturday: “You know Aries and Cancer and Draco and Libra. Leo and Pisces and Virgo and Hydra. But do you recall, the pointiest asterism of all? Triangulum, the three-sided asterism, had a very pointy shape. And if you didn’t know it, you could say it poked an ape.” Sorry. Some stores have started sending out their Christmas catalogs and that has put me in the mood to modify some Christmas songs. Anyway, Triangulum is a small constellation between the more prominent Andromeda and Aries. Its main feature is a skinny triangle oriented parallel to the ground and two and a half fists held upright and at arm’s length above the east-northeastern horizon at 10:00 p.m.

Sunday: The September full moon goes by many names. The Western Abenaki call it the Corn Maker Moon because of the impending harvest. The Tlingit call it the Child Moon because this is the time of year many animals wean their young. The Ojibwe call it the Falling Leaves Moon because the trees are starting to lose their leaves. This month, everyone in the Eastern Hemisphere will call it the Red Moon because there will be a total lunar eclipse visible throughout that hemisphere. During a total lunar eclipse, the Earth’s atmosphere acts like a prism and spreads the Sun’s white light into its component colors, with the red light hitting the moon. If you have friends in the Eastern Hemisphere, send them the link https://www.timeanddate.com/eclipse/lunar/2025-september-7 for more information.

For more about full moon names, go to https://www.almanac.com/full-moon-names.

Monday: Fomalhaut, the southernmost bright star visible from the northern USA, is one fist above the south-southeastern horizon at 11:00 p.m. In 2008, Fomalhaut and its surroundings became the first star system with an extrasolar planet to be directly imaged. See the family photo at https://apod.nasa.gov/apod/ap081114.html.

Tuesday: Saturn is one fist above the east-southeastern horizon at 9:00 p.m.

Wednesday: Mars and the bright star Spica are less than a half a fist above the west-southwestern horizon at 8:00 pm. Reddish mars is to the upper right of the brighter Spica.

Thursday: Earlier this week, you read about Fomalhaut, the second brightest star with a planet. The brightest star known to have a planet is Pollux, in the constellation Gemini. (First vs. second brightest is meaningless here because they are nearly identical in magnitude, 1.15 vs. 1.16.) Pollux is four and a half fists above due east at 5:30 a.m., right below its “twin” star Castor. Read more about Pollux at https://skyandtelescope.org/astronomy-news/meet-pollux-red-giant-exoplanet/.

Friday: Venus is two fists above due east at 6:00 a.m. Jupiter is four and a half fists above the east-southeastern horizon, to the lower right of Pollux and Castor.

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.

The Ellensburg, WA sky for the week of August 30, 2025

Saturday: “Excuse me, do you have the time?” 

“No, but the Big Dipper does.”

You can use the orientation of the Big Dipper to tell time with a precision of about 15-30 minutes. First, find the two stars at the far end of the Big Dipper cup, the stars that do not touch the handle. Draw an imaginary line segment starting at the North Star and passing through the two Big Dipper cup stars. Now, draw a big circle around the North Star. Your circle is a 24-hour clock. Number the circle from 0 hours at the top, counterclockwise to 12 hours at the bottom of the circle, and back up to 24 hours at the top. (O hours and 24 hours are the same on this clock because the day is 24 hours long.) The hour number on the big circle closest to where your imaginary line intersects this circle is called your raw time. Due to the location of the Big Dipper compared to the rest of the stars, the time nearest the intersection (the raw time) is correct for March 6. For any other night, subtract two times the number of months the current date is after March 6 from the raw time. For example, let’s say the imaginary line between the North Star and the Dipper stars is pointed to the right. That means the raw time is 18 hours or 6 p.m. If you made this observation tonight, which is six months after March 6, you would subtract two times six or 12 hours from the raw time. Don’t forget to convert for daylight savings time if needed. If you prefer a more visual tool, and a fun project to do with your kids, there is a simple “star clock” template and instructions at https://skyandtelescope.org/observing/make-a-star-clock/. Use this paper star clock whenever your watch is broken. The Big Dipper is in the northwestern sky at 9:00 p.m. tonight.

Sunday: Mars is about a half a fist above the western horizon at 8:30 p.m. Saturn is rising in the east at this time. By 9:30 p.m., Saturn is one fist above the eastern horizon.

Monday: Labor Day was the brainchild of labor unions and is dedicated to American workers. The first Labor Day was celebrated in 1882. The Greek mythical hero Hercules probably wished there was a Labor Day to commemorate his work. As punishment for killing his family while he was temporarily insane, he had to perform twelve nearly impossible tasks such as killing monsters or stealing things from deities. Hmmm. Maybe we shouldn’t commemorate his labors. But we can enjoy his constellation. The keystone asterism representing the body of Hercules is six fists above the western horizon at 10:00 p.m. For more information about the Labors of Hercules, go to http://goo.gl/ozVF5.

Tuesday: Had the script been written a little differently for a well-known Robin Williams movie, we might have heard Mr. Williams shout, “Goooood Morning Orion the hunter.” Orion is typically thought of as a winter constellation. But it makes its first appearance in the early morning summer sky. The lowest corner of Orion’s body, represented by the star Saiph (pronounced “safe”), rises at 2:45 a.m. By 5:30 a.m., Orion’s belt is three fists above the southeastern horizon.

Wednesday: School starts this week, so it is time for a little geometry review. A square is a regular quadrilateral. This means it has four equal sides, four equal angles, and wears old fashioned clothing. Go outside at 9:30 p.m. tonight with a notebook in hand to sketch one. The Great Square of Pegasus is balancing on its corner about two fists above the eastern horizon. The top corner of the square is two fists above the bottom corner. The other two corners are to the left and right of the line segment connecting the top and bottom corners.

Thursday: Jupiter, Venus, and Mercury make a line in the early morning sky. At 5:45 a.m., Jupiter is four fists above the eastern horizon. Venus, the brightest of the three, is two fists above the eastern horizon. Mercury is right above the east-northeastern horizon.

Friday: Geometry review, part 2. Go outside at 9:30 p.m. tonight with a notebook in hand. (Good teaching involves a little repetition.) A triangle is a polygon with three corners and three line segments as sides. A good example is the Summer Triangle made up of the bright stars Vega, Deneb, and Altair. Altair is five fists above the southern horizon. Vega, the brightest star in the triangle, is seven and a half fists above the southwestern horizon. Deneb is a little bit east of straight overhead.

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.

The Ellensburg, WA sky for the week of August 23, 2025

Saturday: The moon is almost directly between the Earth and the Sun today. That means you won’t be able to see it. But that does not mean it doesn’t exist. Contrary to the belief of toddlers and immature politicians, just because you can’t see something doesn’t mean it doesn’t exist. (Note a double negative statement followed by a triple negative statement. I’m not unsorry about that.) Now, back to the science. What would happen to the Earth if the moon really didn’t exist? In that 2013 blockbuster Oblivion, aliens destroy the moon and Tom Cruise survives. In real life, the long-term effects on the Earth would be devastating to life as we know it. The moon stabilizes the spin axis of the Earth keeping the seasons fairly uniform over time. For more information on what would happen to the earth if the moon were destroyed, go to https://www.popsci.com/what-would-happen-if-moon-suddenly-disappeared/. For more information on Thomas Cruise Mapother IV, go to http://en.wikipedia.org/wiki/Tom_Cruise.

Sunday: School starts soon. One of the most important lessons to learn in science class is to always save your data. Even if the data looks “wrong” or you don’t think it contains essential information, you never know what future researchers might find in it. Two years ago, Kepler space telescope scientists reanalyzed older data and discovered an Earth-sized planet orbiting in the habitable zone of its host star. It turns out the previous computer algorithm misidentified it. Maybe there are other Earth-cousins hiding in the data somewhere. Read more about it at https://www.nasa.gov/press-release/earth-size-habitable-zone-planet-found-hidden-in-early-nasa-kepler-data.

Monday: Mars is a half a fist above the western horizon at 8:45 p.m. Soon it will be lost in the glare of the Sun’s light.

Tuesday: “The sky is black (or light polluted), the stars are white (or red or orange or yellow or blue), the whole world gazes upon the sight (except where there are too many city lights or people are lazy.” Wow. It is difficult to write a flowing set of lyrics when there are so many parenthetical thoughts. Most people think of the sky’s blackness as a lack of stars. But dark patches in the Milky Way are actually massive clouds of dust that are blocking the stars behind them. Two of the most prominent are dark nebulae B142 and B143 in the constellation Aquila the eagle. These are easy to find and enjoy with binoculars. First find the bright white star Altair, five fists above due south at 10:30 p.m. Then move your binoculars up and to the right a little bit to the next bright star Tarazed, about one fifth as bright. B142 and B143 are to the upper right of Tarazed. They make an “E” shape in the sky; fitting because American astronomer E. E. Barnard first proposed that these were dust clouds and not simply big spaces between the stars. For more information about dark nebulae, including many more to look at with binoculars, go to https://goo.gl/9tiqdh.

Wednesday: Saturn is two fists above the east-southeastern horizon at 11:00 p.m.

Thursday: The star FG Sagittae, in the constellation Sagitta the arrow, is changing before our eyes. Over the past 60 years, FG Sagittae has turned from blue to white to orange, indicating that it has puffed up and gotten cooler. The star is too dim to be seen with the naked eye, but the constellation looks like a small, horizontal arrow six fists above due south at 10:30 p.m.

Friday: Jupiter, Venus, and Mercury make a line in the early morning sky. At 5:15 a.m., Jupiter is three fists above due east. Venus, the brightest of the three, is one and a half fists to the lower left of Jupiter. Mercury is right above the east-northeastern horizon.

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.

The Ellensburg, WA sky for the week of August 16, 2025

Saturday: Not every woman in the Black family is evil. Let’s focus on the good. Andromeda Black, Bellatrix’s sister, is a good witch and the mother of Tonks, a young witch from the last few Harry Potter books. (If these Harry Potter references are confusing, you better start reading the books.) Andromeda the constellation is an interesting one. It contains the Andromeda galaxy, the most distant object visible with the naked eye from a dark site. To locate the Andromeda Galaxy, first find the Great Square of Pegasus. At midnight, the left-hand corner of the square is four fists held upright and at arm’s length above the eastern horizon. Less than two fists to the left and down a little bit is another star, the same brightness as the star at the corner of the square. From that star, hop about a half a fist up to a star that is about one fourth as bright. Less than another half fist in the same direction is a fuzzy oval patch of light known as the Andromeda Galaxy. The galaxy is impressive to see in binoculars. It consists of about one trillion stars and is 2.5 million light years away.

Sunday: Arcturus is two and a half fists above due west at 10:15 p.m. This star, whose name means bear watcher, is the brightest in the sky’s northern hemisphere. It follows Ursa Major, the Great Bear, around the North Star. Arcturus is the closest giant star to Earth. It is one of the few stars whose diameter can be measured directly rather than being inferred from its density and mass, which themselves are derived from other parameters.

Monday: Mars is a half a fist above the western horizon at 9:00 p.m. An hour later, at 10:00 p.m., you can find Saturn a half a fist above the eastern horizon.

Tuesday: Mercury will be as far away from the Sun in the sky as it will get this orbital cycle. This "farthest away" point is known as the planet's greatest elongation. Since Mercury is in the morning sky, it is west of the Sun and this occurrence is called the greatest western elongation. This morning, Mercury is half a fist above the east-northeastern horizon at 5:15 a.m. Over the next few weeks, Mercury will move toward the Sun in the sky. By mid-October, it will be visible in the evening sky.

Wednesday: The moon, Venus, and Jupiter make a small right triangle low in the eastern sky at 5:30 a.m. Venus is to the lower right and Jupiter is to the upper right of the moon. As a bonus, the bright stars Pollux and Castor in the constellation Gemini are to the upper left of the moon.

Thursday: All stars rotate. Our Sun takes a little less than one Earth month to rotate once on its axis. Astronomers studied the relationship between mass, stellar rotation, and planetary formation by aiming NASA’s recently retired Kepler space telescope toward the Pleiades open star cluster. All 1,000 stars in this group are nearly the same age, 125 million years old. Since all the stars are the same age and formed from the same set of materials, astronomers have the ideal “laboratory” to isolate the role star mass plays on star rotation and evolution. Read more about the findings at https://www.jpl.nasa.gov/news/kepler-watches-stellar-dancers-in-the-pleiades-cluster. See the Pleiades for yourself, about a half a fist above the east-northeastern horizon at 11:30 p.m.

Friday: Seventeenth century astronomers documented the appearance of a new star, or “nova,” in 1670. However, as modern astronomers studied the records of the star, called Nova Vulpeculae 1670, they realized it didn’t have the characteristics of a typical nova because it didn’t repeatedly brighten and dim. It brightened twice and disappeared for good. Turning their telescopes to the region, they discovered the chemical signature to be characteristic of a very rare collision of two stars. For more information about this discovery, go to http://goo.gl/rJnC2G. Nova Vulpeculae 1670 is right below the binary star system Alberio, the head of Cygnus the swan. Alberio is seven fists above due south at 10:30 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.