Thursday, January 19, 2023

The Ellensburg, WA sky for the week of January 21, 2023

Saturday: Winter is the best season for finding bright stars. And if you only want to set aside a few minutes, 10:00 p.m. tonight just might be the best time because the winter hexagon is due south. Starting at the bottom, find Sirius, the brightest star in the night sky, two and a half fists held upright and at arm’s length above the southern horizon. Going clockwise, Procyon (8th brightest star in the night sky) is about two and a half fists to the upper left of Sirius. Pollux (17th brightest) is about two and a half fists above Procyon. Capella (6th brightest) is about two and a half fists to the upper right of Procyon and close to straight overhead. Going back to Sirius at the bottom, Rigel (7th brightest) is about two and a half fists to the upper right of Sirius. Aldebaran (14th brightest) is about three fists above Rigel. Adhara (22nd brightest) is a little more than a fist below Sirius and Castor (24th brightest) is right above Pollux. Betelgeuse (10th brightest) is in the center of the hexagon, five fists above due south. That’s nine of the 24 brightest stars visible in the night sky congregated in one small section of the sky. 

Sunday: At 5:30 p.m., Venus and Saturn are less than a half a degree apart in the sky. They are so close together that you couldn’t even squeeze the full moon between them. See Venus and Saturn one fist above the southwest horizon. For comparison, the moon is below the two planets.

Monday: You think wintertime weather is bad in Ellensburg. Astronomers have discovered storms and earth-sized clouds on a brown dwarf. These are cool, small stars that are not massive enough to fuse hydrogen atoms and fuse hydrogen. In fact, they are more similar to gas giant planets such as Jupiter than to the Sun. Luckily, astronomers are getting better at predicting this weather. That means you can plan your brown dwarf picnic and it can be more enjoyable. For more information, go to https://www.nasa.gov/feature/jpl/scientists-improve-brown-dwarf-weather-forecasts 

Tuesday: Do you ever take photos to spy on your neighbors? The Hubble Space Telescope does. In 2019, Hubble scientists released the best 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/. At 7:00 p.m., the Triangulum Galaxy is six and a half fists above the southwestern horizon. It is barely visible with binoculars. First find the Great Square of Pegasus, centered four fists above the western horizon. It is tripped so it appears to be balanced on a corner. Go to the top star in the tilted square. Move your binoculars about one binocular field of view, about a half a fist above the corner star. You’ll see a pair of stars of similar brightness in that field of view. Then move your binoculars up another field of view to two stars that are a little brighter and a little farther apart than the previous pair. The brighter of the two is named Mirach. About one binocular field of view, or about a half a fist to the right of Mirach is the largest galaxy in our neighborhood and the brightest in the sky: the Andromeda Galaxy. About one binocular field of view, or about a half a fist to the left of Mirach is the Triangulum Galaxy, also known as Messier 33 (M 33). The Triangulum is much more challenging to see.

Wednesday: Draco Malfoy makes an appearance in all seven books of the Harry Potter series. Perhaps you’ve heard of these. But the constellation Draco the dragon makes an appearance in the sky every night. It is a circumpolar constellation as viewed from Ellensburg meaning it never goes below the horizon. The head of the dragon is one fist above due north at 9:30 p.m. Eltanin, the brightest star in the constellation, is at the lower left-hand corner of the trapezoid-shaped head of Draco.

Thursday: Mars is nearly seven fists above due south at 8:00 p.m.

Friday: Mercury is a half a fist above the southeastern horizon at 7:00 a.m.

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.

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