The Ellensburg, WA sky for the week of May 23, 2020

Saturday:  Moon, Mercury, Venus make a small triangle low in the west-northwestern sky right after sunset. Mercury if the dimmest of the three objects, at the top of the triangle.

Sunday:  In 1979, the group Foreigner recorded the song “Head Games”. They could have been singing about the constellations Hercules and Ophiuchus when they said “head games, it’s just you and me baby, head games, I can’t take it anymore” because the heads of these two constellations have been right next to each other in the nighttime sky for all of human history. And just to make it easy for you, a star that bears an Arabic name that means “the head” represents each head. In Hercules, it's Ras Algethi (head of the kneeler); in Ophiuchus, Ras Alhague (head of the serpent charmer). At 11 p.m., Ras Alhague, the brighter of the two, is three and a half fists held upright and at arm’s length above the east-southeast horizon. Ras Algethi is about a half a fist to the upper right of Ras Alhague.

Monday: In 1982, the British group Bow Wow Wow first sang, “I Want Candy”. In May 2019, NASA finally granted that wish by releasing images of Mars’ moon Phobos looking like candy.  The thermal imaging camera on NASA’s long lived Odyssey orbiter took a series of images of the full phase of Phobos. The resulting composite, looking like a many layered jaw-breaker, shows how the temperature varies throughout the small moon. This temperature distribution, in turn, can help astronomers determine what the moon is made of. For more about this yummy treat, go to https://www.jpl.nasa.gov/news/news.php?feature=7398. Mars is one and a half fists above the southeast horizon at 4:00 a.m.

Tuesday: It looks so peaceful up there. But life is not peaceful for Jupiter. According to a recent study by astronomers, Jupiter gets hit by a 5-20 meter diameter asteroid 10 to 65 times a year. For comparison, the object that exploded over the Russian city of Chelyabinsk in 2013 was 20 meters in diameter. Earth gets hit by a 20-meter asteroid about once every 50 years. For more information, go to https://goo.gl/RxPc5G. Jupiter is two fists above the south horizon at 4:30 a.m. Saturn is a half a fist to the left of Jupiter.

Wednesday: Antares is a half a fist above the southeastern horizon at 10:00 p.m.

Thursday:  Altair, the lowest star in the Summer Triangle, is one fist above due east at 11:00 p.m.

Friday: The CWU campus is closed. But astronomy learning lives on! The Physics Department and the College of the Sciences is hosting a First Saturday VIRTUAL planetarium show Saturday, June 6 from noon to 1:00 p.m. CWU professor Bruce Palmquist will host the Intergalactic Planetarium Short “Film” Festival. You’ll see a variety of short Worldwide Telescope Tours created by CWU Astronomy and Douglas Honors College students featuring videos about the Solar System, nebulas, and Harry Potter astronomy. Stay at home, practice good physical distancing, and visit https://cwu.zoom.us/meeting/register/tJcuduChqz8jGdQ86cUyKBKmR2K_jdcEqSx- to register for the Virtual tour.

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.