The Ellensburg WA sky for the week of 2/16/19

Saturday:  “Oooo, they’re little runaways. Orion’s stars moved fast. Tried to make a getaway. Ooo-oo, they’re little runaways,” sang Bon Jovi in his astronomical hit “Runaway.  At least that’s what I hear when I listen to the song. After all, it fits the recently calculated trajectory of AE Aurigae, Mu Columbae, and 53 Arietis. Extrapolating the actual motion of these three stars back in time, they were all in the location of the star-forming region called the Orion Nebula a few million years ago. What kicked these stars out? Not paying rent? Excessive partying? No, it was simply gravitational interactions with nearby stars. Find out more about the eviction at http://goo.gl/UeLwKQ. Orion is about four fists held upright and at arm’s length above due south at 8 p.m.

Sunday: Saturn is about a thumb width below the very bright Venus, one fist above the southeast horizon at 6 a.m.

Monday: “Happy Birthday to you. Happy Birthday to you. Happy Birthday dear Pluto. Happy Birthday to you.” On this day in 1930, Clyde Tombaugh discovered Pluto, at that time classified as the ninth planet. However, as astronomers started discovering a lot of similar objects in that part of the solar system, they realized that had a classification crisis on their hands. Should everything in this region of the solar system be named a planet? Eventually the International Astronomical Union (IAU) reclassified Pluto and all future Pluto-like objects as dwarf planets. Pluto is way too dim to be seen with binoculars or small telescopes. But you can check out its general location, one fist to the lower left of Saturn and Venus, a half a fist above the southeast horizon at 6 a.m.

Tuesday: How did life begin on Earth? Well, there’s a mommy and a daddy and they…. Oh, wait. You said “on Earth”. Many astronomers think that the key elements for life such as carbon, oxygen, and sulfur came from Theia, the Mars-sized object that collided with the Earth about 4.5 billion years ago. These elements would have boiled out of the primordial Earth so astronomers have been looking for an extraterrestrial delivery vehicle. According to computer models, Theia meets the criteria. Read more about this at

https://www.skyandtelescope.com/astronomy-news/did-a-mars-size-body-bring-life-essential-elements-to-earth/.  Mars is four fists above the south-southeast horizon at 7 p.m.

Wednesday: Clyde Tombaugh discovered the first planet 9. Will you discover the new Planet 9? You and thousands of others will have the opportunity to comb through images of the sky from NASA’s Wide-field Infrared Survey Explorer (WISE). You’ll view short “flipbook” movies of the same patch of sky on different nights. Any point of light that moves could be Planet 9 or another undiscovered Solar System object. Join the search for Planet 9 at https://www.zooniverse.org/projects/marckuchner/backyard-worlds-planet-9.

Thursday: Mercury is one fist above the west-southwest horizon at 6 p.m.

Friday: The Stargate movies and TV shows have access to a portal to other planets. Harry Potter has access to a portal to the Chamber of Secrets. You have access to a Portal to the Universe. This portal is not in Moaning Myrtle’s bathroom but is on the web at http://www.portaltotheuniverse.org/. It is a repository of up-to-date astronomy news, blogs, and podcasts. A recent story highlights how planet hunters like you and Clyde Tombaugh look for other planetary systems. Astronomers at the Center for Astrophysics: Harvard and Smithsonian just discovered a planetary disk that has been flipped perpendicular to the orbital plane of the binary star system it orbits. Until this discovery, a protoplanetary disc orbiting perpendicular to its host stars was only a theory. Read more about this discovery at https://www.cfa.harvard.edu/news/2019-01.

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.