Thursday, August 20, 2026

The Ellensburg, WA sky for the week of August 22, 2026

Saturday: Every star rotates. 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.

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: Look for Venus half a fist above the west-southwestern horizon at 8:45 p.m. Then go inside and read a book. Come back outside at 10:45 p.m. to see Saturn one fist above the eastern horizon.

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: If you’d like to learn more about planets and moons, the CWU Lydig Planetarium has free shows at 3:00 p.m. and 5:00 p.m. today. They are in Discovery Hall, room 101. Here is a Google maps link: https://maps.app.goo.gl/Nwp1e5t7qXk5bfE9. Parking on campus is free after 4:30 p.m.

Thursday: The 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. Tonight, you’ll be tempted to call it a blood moon because it is a nearly total lunar eclipse visible throughout the whole USA. 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. This eclipse will be 93% total as viewed from Ellensburg so it will look red. The partial eclipse will start as the moon rises and will be maximum at 9:12 p.m. The partial eclipse will end at 10:51 p.m. For more information, including where to see it in other parts of the country or world, go to https://www.timeanddate.com/eclipse/lunar/2026-august-28.

Friday: 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.

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.

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