Thursday, October 23, 2025

The Ellensburg, WA sky for the week of October 25, 2025

Saturday: Halloween is this Friday. If you need costume ideas, look low in the sky at 7:15 p.m. Arcturus is about one fist held upright and at arm’s length above the western horizon. In The Hitchhiker’s Guide to the Galaxy, Arcturus is home to giant ships called Arcturan Megafreighters and oversized megafauna like the Arcturan Megaleech and Arcturan Megacamel. Capella is about one fist above the northeastern horizon. In the second season episode of Star Trek: The Original Series called Friday’s Child, the Enterprise goes to Capella IV to negotiate a mining contract for a valuable mineral. While there, they get tangled up with warring factions and a Klingon. Inspiration from these two stars might help you win the costume contest as you go dressed as Captain Kirk, a Klingon, or an Arcturan Megaleech. For more about stars and planets featured in popular fiction, go to https://en.wikipedia.org/wiki/Stars_and_planetary_systems_in_fiction.

Sunday: Saturn is three fists above due southeast at 8:00 p.m.

Monday: According to the “One world, group hug, love everyone” philosophy, political borders are human-made and can’t be seen from space so why can’t we all just get along. According to real world pragmatic discoveries, some human-made political borders CAN be seen from space. Since 2003, India has illuminated its border with Pakistan to prevent illegal crossings. In 2011, astronaut Ron Garan took a picture of that border from the International Space Station. For more information, including the photo, go to http://goo.gl/mY8xG.

Tuesday: Did you know that moons and dwarf planets share some similar features? The five largest moons of Uranus have the same heat signatures as the largest dwarf planets such as Pluto and Eris. That means they are relatively dense and don’t immediately radiate away all their daytime-absorbed heat at night. Read more about Uranian moons at https://skyandtelescope.org/astronomy-news/uranian-moons-are-like-dwarf-planets/. Uranus can easily be seen with typical binoculars. It is about a half a fist to the lower right of the open star cluster called the Pleiades. Move the Pleiades to the upper left of your binoculars field of view. Uranus will be on the lower right. Uranus is the object that will have moved over the course of a few nights.

Wednesday: 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 evening sky, it is east of the Sun, so this occurrence is called the greatest eastern elongation. Mercury is right above the southwestern horizon at 6:15 p.m. Over the next two weeks, Mercury will move toward the Sun in the sky. By late November, it will be visible in the morning sky.

Thursday: At 7:00 a.m., Venus is about half a fist above the east-southeastern horizon and Jupiter is six fists above the south-southwestern horizon.

Friday: Halloween weekend is a great time to celebrate the dead. Dead stars, that is. Black holes and neutron stars are the end of life for super massive stars. But intermediate mass stars such as our Sun end up as white dwarfs. After fusing hydrogen into helium for most of its life and fusing helium into heavier elements for a brief period at the end of its life, the Sun will end up with a core of heavier elements that can no longer produce energy through nuclear fusion. Without the outward radiation pressure from fusion energy resisting the inward pull of gravity, the Sun will end up as a super-dense sphere of atoms in which the electrons are squished onto the nuclei. It will be an object with nearly all its mid-life mass but in a volume about the size of the Earth. The easiest white dwarf to see is in the triple star system called Keid, from the Arabic word “qayd” meaning eggshells. Learn more about Keid, also called 40 Eridani, including map of how to find it at

https://www.skyandtelescope.com/observing/trick-or-treat-with-white-dwarfs/. At midnight (scary), Keid is two and a half fists above due southeast. You’ll need a small telescope to see it. First find Rigel, the brightest star in the constellation Orion. It is one and a half fists above the east-southeastern horizon. Then use binoculars to find the right area. With Rigel at the bottom of your field of view. There should be a star near the top of your girls of view that is about one sixth as bright. This star is called Cursa. Next, move your binoculars up and to the right about one and a half field of view diameters. Look for two stars close together, each about one third as bright as Cursa. Finally, move your binoculars straight over to the right about one and a half field of view diameters. The lower of these two stars is Keid or 40 Eridani A. You’ll need a telescope to see the white dwarf, called 40 Eridani B.

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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