Thursday, September 25, 2025

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.

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