Thursday, August 28, 2025

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.

Wednesday, August 20, 2025

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.

Wednesday, August 13, 2025

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.

Thursday, August 7, 2025

The Ellensburg, WA sky for the week of August 9, 2025

Saturday: One minor Harry Potter character actually has two well-known star names: Regulus Arcturus Black, the brother of Sirius Black who is Harry Potter’s godfather. Regulus Black was a former follower of Voldemort, the bad guy of the Harry Potter series. However, Regulus tried to dissociate himself from Voldemort and was killed. In the sixth book, Harry found an important note written by someone known only by the initials R.A.B. Hmmm. R.A.B. Regulus Arcturus Black perhaps? Regulus the star is right in line with the Sun at this time of year so it is not visible. Arcturus, the second brightest star visible in the nighttime sky in Washington and at Hogwarts, is about two and a half fists held upright and at arm’s length above the western horizon at 11:00 p.m.

Sunday: Venus and Jupiter are right next to each other, low in the eastern sky for the next few mornings. At 5:00 a.m., they are two fists above the eastern horizon. Venus is brighter and to the upper right of Jupiter. Over the next few weeks, Venus will move to the lower left, down toward the east-northeastern horizon, and eastward compared to the background stars.

Monday: The Perseid meteor shower peaks this morning and tomorrow morning. In case you decide to stay in bed this week, the shower is active until about September 1 so you may still enjoy an increased number of meteors later. The moon is in the waning gibbous phase so its light will obscure all but the brightest meteors. The meteors appear to come from a point just below the W of the constellation Cassiopeia. This point is about three fists above the northeast horizon at 11:00 p.m. By dawn, this point is nearly straight overhead. For tips about optimizing your viewing this year, go to https://earthsky.org/?p=165416. As your Mother might say, dress warm and sit in a comfortable chair for maximum enjoyment. These meteors are sand to pea-sized bits of rock that fell from Comet Swift-Tuttle. They travel about 40 miles per second as they collide with the Earth and burn up in the atmosphere.

Tuesday: Bellatrix Lestrange is Sirius Black’s cousin. But certainly not kissing cousins. They are killing cousins. Bellatrix kills Sirius in a fight at the Ministry of Magic. Bellatrix the star is the third brightest star in the constellation Orion the hunter. It is two and a half fists above the east-southeastern horizon at 5:00 a.m.

Wednesday: Of course, Bellatrix is in cahoots with “he who must not be named.” Now, that’s a poorly written sentence, using an obscure synonym for “conspiring” and a vague reference to someone. I must be under the curse “writicus dreadfulium.” Clearly this is the work of Tom Riddle, whose mother is named Merope Gaunt. Merope is a star in the Pleiades, an open star cluster about five and a half fists above the southeastern horizon at 5:15 a.m. Mercury is a half a fist above the east-northeastern horizon at this time.

Thursday: Draco Malfoy, Harry Potter’s young nemesis, is related to Sirius Black. Draco’s mother, Narcissa Black (Sirius’ cousin), helped develop a plan to trap Harry at the Ministry of Magic in the fifth book. Draco’s namesake, the constellation Draco the dragon, is one of the largest constellations in the sky, winding around the North Star. Draco’s head is a four-sided figure a little on the northwest side of straight overhead at 10:00 p.m.

Friday: Antares, the brightest star in the constellation Scorpius, is one and a half fists above the south-southwestern horizon at 9:00 p.m. Draco Malfoy was so impressed with this constellation name that he used it for the first name of his son. Mars is half a fist above the western horizon at this time.

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, July 31, 2025

The Ellensburg, WA sky for the week of August 2, 2025

 Saturday: Star light. Star bright. The first star you see tonight might be Vega, nearly seven fists held upright and at arm’s length above the eastern horizon right after sunset. 

Sunday: Mars is half a fist above the western horizon at 9:30 p.m. In case that is not interesting enough for you, look to the south. The bright star Antares, which means rival of Mars, is right above the moon.

Monday: It is often said that Earth is a water world because about 70% of the Earth’s surface is covered by water. What would it look like if all that water on the surface were gathered up into a ball? That “ball” would be about 700 km in diameter, less than half the diameter of the Moon. The Astronomy Picture of the day shows us right here https://apod.nasa.gov/apod/ap120515.html.

Tuesday: Venus, the brightest point of light in the sky, is two fists above the eastern horizon at 5:00 a.m. Jupiter is about a half a fist to the lower left of Venus.

Wednesday: The Gemini twins, first Castor and then Pollux, rise just before the Sun. At 5:00 a.m., Pollux is one and a half fists above the northeastern horizon. A slightly dimmer Castor is half a fist above it. Pollux is the brightest star, as observed from Earth, known to have a planet orbiting it. The planet, creatively called Pollux b, has about twice the mass of Jupiter.

Thursday: If you want to show your loved ones a celestial sign that they should hang up their clothes, show them Brocchi's Cluster, commonly known as the Coat Hanger cluster because of its resemblance to an upside-down coat hanger. The cluster is about six fists above due south at 11:20 p.m., midway between Altair and Vega, the two brightest stars in the Summer Triangle. You'll need binoculars to make out the shape. First find Altair five fists above the southern horizon. Slowly move your binoculars up toward Vega. You will run into the coat hanger along the way. And while you are at it, put away your shoes.

Friday: Tonight’s August full moon is traditionally called the full sturgeon moon by Midwest and northeastern Native American tribes because the sturgeon in lakes in this part of the country were easiest to catch during this full moon time. The Ojibwe in the Midwest harvest wild rice in August, calling the August full moon the Ricing Moon.

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, July 24, 2025

The Ellensburg, WA sky for the week of July 26, 2025

Saturday: At 9:30 p.m., the bright star Regulus is to the lower right of the crescent moon, low on the west-northwestern horizon. Mars is nearby, one fist held upright and at arm’s length above the western horizon.

Sunday: Have you ever planned a vacation to a place because it was supposedly the up-and-coming locale? Then, when the vacation time finally arrives, you find out the place doesn’t live up to its billing. Over the past decade, astronomers strengthened earlier findings about the planetary system of the star Tau Ceti, one of our closest Sun-like star neighbors at 12 light years away. It has four planets classified as “super-Earths.” Two of the planets are on the edge of the habitable zone where the temperature is just right for having liquid water on their surface. Time for a va-ca-tion! Well, not so fast. Astronomers have only a lower limit to the planet masses so they may be too massive for complex life to form. And the Tau Ceti system has ten times as much mass in dust and rocks as our own solar system. So, you’ll want to do some research before you travel there. Tau Ceti is one and a half fists above the southeast horizon at 3:00 a.m. For more information about the system, go to https://skyandtelescope.org/astronomy-news/four-exoplanets-may-orbit-nearby-sun-like-star/.

Monday: Saturn is a half a fist above the eastern horizon at 11:30 p.m.

Tuesday: The Southern Delta Aquarid meteor shower peaks tonight, tomorrow night, and on into mid-August. Meteor showers are named after the constellation from which the meteors appear to originate. These meteors appear to come from a point in Aquarius near the star Delta Aquarii, also known as Skat. This point is about one and a half fists above the southeastern horizon at 1:00 am tonight. You can follow this point throughout the night, as it will remain a fist above Fomalhaut, the brightest star in that section of the sky. The Moon is in the waxing crescent to first quarter phase this week meaning it will not be up for many hours each night. For more information about this year’s shower, go to https://earthsky.org/?p=159138. As your mother might say, dress warmly and sit in a comfortable chair for maximum enjoyment. Meteors are tiny rocks that hit the Earth and burn up in the atmosphere.

Wednesday: At 4:30 a.m., Jupiter is one fist above the east-northeastern horizon and Venus is one and a half fists above the eastern horizon.

Thursday: Mizar is a well-known binary star in the constellation Ursa Major. You can find it at the bend in the Big Dipper handle, three fists above due northwest at midnight. Its name is Arabic for waistband. Mizar has an optical double called Alcor, which is less than a pinky width away and can easily be seen with the naked eye. Optical doubles are stars that are close together in the sky but do not orbit a common center of mass as true binary stars. Not wanting to deceive sky gazers who call Alcor and Mizar a binary star, two stars that DO orbit a common center of mass, Mizar actually is a binary. It was the first binary star system discovered using a telescope. Mizar A and Mizar B are about 400 astronomical units apart from each other and about 80 light years from Earth. 400 astronomical units is about 10 times the distance between the Sun and Pluto.

Friday: The Perseid meteor shower peaks in a week and a half. But there will be an increased number of meteors over the next two weeks. If the Moon is out when you want to look, position yourself so you are blocked from the Moon’s light. The meteors appear to come from a point just below the W of the constellation Cassiopeia. This point is about two and a half fists above the northeast horizon at 11:00 p.m. By dawn, this point is about seven fists above the northeast horizon. If you fall asleep or forget to set your alarm, you will be able to observe this shower from about 11:00 p.m. to dawn for the next two weeks in about the same location in the sky.

The Perseid shower is one of the longest lasting showers. For tips about optimizing your viewing this year, go to https://earthsky.org/?p=165416. These meteors are sand to pea-sized bits of rock that fell off Comet Swift-Tuttle. They travel about 40 miles per second as they collide with the Earth and burn up in the atmosphere.

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, July 17, 2025

The Ellensburg, WA sky for the week of July 19, 2025

Saturday: As of July 17, both the US Senate and House of Representatives have rejected the White House NASA budget cuts and propose to keep NASA’s budget nearly unchanged. But your favorite NASA mission isn’t out of danger yet. Because of the White House request, NASA has directed teams to start submitting project termination plans. One of the missions in danger is the Deep Space Climate Observer (DSCOVR), a collaboration between NASA, NOAA, and the U.S. Air Force. Since reaching orbit in 2015, it has been Earth’s primary warning system for dangerous solar magnetic storms.

Sunday: Take a two and a half hour walk today. Too long, you say? 56 years ago today, Neil Armstrong and Buzz Aldrin took the first ever walk by humans on another world. They spend two and a half hours setting up scientific instruments and collecting rocks for study back on Earth. Their colleague Michael Collins orbited the Moon in the spacecraft the astronauts would use to return to Earth. While everyone seems to know about Armstrong and Aldrin, spend some time learning more about Collins by reading https://time.com/5624528/michael-collins-apollo-11/.

Monday: At 4:30 a.m., Venus is one and a half fists above the eastern horizon, right below the moon. Jupiter is a half a fist above the east-northeastern horizon.

Tuesday: Mars is a little more than one fist above the western horizon at 9:30 p.m.

Wednesday: Zubenelgenubi, the second brightest star in the constellation Libra. The name means "southern claw", a holdover from the time when this part of the sky was associated with the neighboring constellation of Scorpius the scorpion. Zubenelgenubi is a binary star system, easily seen with binoculars as a white and yellow pair. To a person living on a planet orbiting the dimmer of the two stars, the brighter star would be nearly as bright as the full Moon appears from Earth. Zubenelgenubi is one and a half fists above due southwest at 10:45 p.m.

Thursday: What you see with the naked eye isn’t all that can be seen. While astronomers can learn a lot from observing the sky in the visible wavelengths, many celestial objects radiate more light, and more information, in wavelengths such as radio, microwave, infrared, ultraviolet, x-ray, and gamma ray. In 2012, NASA launched the Wide-field Infrared Survey Explorer (WISE) to study objects that radiate in the infrared range such as asteroids, cool dim stars, and luminous galaxies. For an interesting comparison of how different wavelengths show distinct aspects of celestial objects, go to http://goo.gl/nvuax. If it weren’t for infrared telescopes such as WISE, astronomers would not know about the significant amount of dust in galaxies. We also wouldn’t know how much brighter than the Sun red supergiant stars are. Antares is a red supergiant star, currently sitting at one and a half fists above the southern horizon at 9:30 p.m. In the visible wavelengths, Antares shines 10,000 times brighter than the Sun. But since Antares is much cooler than the Sun, its energy distribution peaks in the infrared. Across all wavelengths of light, Antares shines 60,000 times brighter than the Sun. The JWST is also an infrared telescope.

Friday: Capella is the fourth brightest star we can see in Ellensburg. It is the brightest northerly star. Actually two stars, a binary star system of two yellow giant stars that orbit each other every 100 days. At 11:30 p.m., Capella is a half a fist above the northern horizon. At this time, the planet Saturn is half a fist above the eastern 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.