The Ellensburg, WA sky for the week of January 25, 2020

Saturday:  Venus is two fists held upright and at arm’s length above the southwestern horizon at 6:00 p.m. For the next few days, you can use Venus, a very bright object, to find Neptune, a very dim object. First find Venus using a pair of 10X50 binoculars and put Venus in the lower right hand portion of the field of view. There should be a medium bright star in the center to upper left portion. Neptune is a very dim point of light between Venus and the medium bright star.  Venus will move upward for the next few weeks. On Monday evening, Venus will have moved upward a little bit such that Neptune will be right below Venus in the field of view. They will even be in the same field of view for small telescopes.

Sunday: Do you ever take photos to spy on your neighbors? The Hubble Space Telescope does. Last week, Hubble scientists released the best ever image of the Triangulum Galaxy, the second closest spiral galaxy to Earth. Hubble’s Advanced Camera for Surveys weaved together 54 separate images to provide enough detail to see 10 million individual stars out of the estimated 40 billion stars in the galaxy. See the pictures at https://www.spacetelescope.org/news/heic1901/. 

Monday: Mars is one and a half fists above the south-southeastern horizon at 6:30 a.m. It rival Antares is one fist to the east of Mars. By using the term “rival”, I am not trying to drum up controversy. The name “Antares” literally means “rival to Mars” because of their similar colors and brightness. And just like real rivalries, the similarities are deceiving. Mars is red because of an abundance of iron oxide, the same material as in rust. Antares is red because its surface glows with a light energy corresponding to red, like the coils of an electric stove. Mars is bright because it is a nearby object reflecting the light of a nearby object. Antares is bright even though it is far away because it is huge, about the same size as Jupiter’s orbit.

Tuesday: At 10:30 p.m., the blue giant star called Adhara is one and a half fists above due south. It is the 22nd brightest star in the sky. Currently over 430 light years away, Adhara was only 34 light years away five million years ago. That proximity made it the brightest star in the nighttime sky at the time.

Wednesday: On these cold mornings, it is difficult to get going. You just want to plop into a chair and sit still. But, are you really sitting still? You’re moving at about 700 miles per hour due to the rotation of the Earth on its axis and 66,000 miles per hour due to the revolution of the Earth around the Sun. If that’s not enough, the entire solar system is orbiting the center of the galaxy at a whopping 480,000 miles per hour! So while you may be sitting still with respect to your living room (and all of the overachievers in your house), you are NOT sitting still with respect to the center of the galaxy. For more information about this concept, go to https://nightsky.jpl.nasa.gov/docs/HowFast.pdf. 

Thursday: If someone gives you a ring and says, “this ring symbolizes our eternal love, just like the rings of Saturn are eternal”, don’t doubt their love. But do doubt their astronomy knowledge. According to data recently analyzed from the Cassini Mission, Saturn’s rings may be only 10 to 100 million years old. As Cassini passed between Saturn and the rings, it was able to get the best estimate yet of the mass of the rings. Saturn’s rings are made mostly of ice and are still very bright and clean. Older rings would be darkened by debris. Also, the ring particles get pulverized by collisions over time. If this relatively low mass of ring particles were older, they would have been destroyed by now. For more information about the lifespan of Saturn’s rings, go to Saturn’s rings https://www.universetoday.com/141272/saturns-rings-are-only-10-to-100-million-years-old/. Saturn is just above the southeastern horizon at 7:00 a.m., to the lower left of the much brighter Jupiter.

Friday: The CWU Physics Department and the College of the Sciences is hosting its monthly First Saturday planetarium show tomorrow from noon to 1 p.m. The CWU Planetarium Outreach and Research Group - the PORGs - will be doing a Valentine’s show about love stories in the sky. The show is free and open to all ages. There will be a show at noon on the first Saturday of every month of the school year hosted by different CWU astronomers and astronomy educators. The CWU Lydig Planetarium is room 101 in Science Phase II, just off the corner of 11th and Wildcat Way, H-11 on the campus map found at https://www.cwu.edu/facility/campus-map.

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.