Thursday, January 17, 2019
The Ellensburg WA sky for the week of 1/19/19
Saturday: Winter is the best season for finding bright stars. And if you only want to set aside a few minutes, 10 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 arms length above the south horizon. Going clockwise, Procyon (6th brightest star visible from Washington state) is about two and a half fists to the upper left of Sirius. Pollux (12th brightest) is about two and a half fists above Procyon. Capella (4th 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 (5th brightest) about two and a half fists to the upper right of Sirius. Aldebaran (9th brightest) is about three fists above Rigel. Betelgeuse (7th brightest) is in the center of the hexagon. Adhara (16th brightest) is a little more than a fist below Sirius and Castor (17th brightest) is right above Pollux. That’s nine of the 17 brightest stars visible in the northern United States in one part of the sky.
Sunday: There is a total lunar eclipse tonight. What could be better than that? A supermoon total lunar eclipse. The Moon is near perigee meaning it is near its closest to Earth. Total lunar eclipses are not as noticeable as total solar eclipses because light still reaches the Moon even when it is completely blocked by the Earth. That is because the Earth’s atmosphere acts like a lens and bends rays of light toward the Moon that would normally miss the Moon. However, that doesn’t mean the Moon looks the same during a total lunar eclipse as it does during a normal full moon.
Sunlight is white. White light is the sum of all of the colors in the visible spectrum (red, orange, yellow, green, blue, indigo and violet). Our atmosphere scatters the blue component of the Sun’s white light. That is why our sky is blue. (If our atmosphere consisted of different gasses, we would likely have a different colored sky.) When the Sun or Moon is near the horizon, the light passes through a lot of the atmosphere meaning a lot of the blue light is scattered and the Sun or Moon looks redder than when it is high in the sky. During a total lunar eclipse, sunlight passes through a large slice of the Earth’s atmosphere. The remaining light that reaches the Moon is reddish. Some people say the fully eclipsed Moon looks Blood Red! These people exaggerate. It arrears a dull reddish color.
From our perspective in the Pacific Time Zone, the partial eclipse stage will start at 7:34 p.m. The Moon will slowly move into the Earth’s shadow and get dark from left to right. At 8:41 p.m., the Moon will be fully eclipsed. The total eclipse lasts until 9:43 p.m. The moon will be moving out of the earth’s darkest shadow or umbra until 10:50 p.m. After that, the moon will look white, just like a normal full moon. Thus, during the entire eclipse, the moon looks white, then black, then red all over. For more information about the eclipse, including information about the specific times for your location, go to https://earthsky.org/tonight/supermoon-lunar-eclipse-january-20-21
Monday: Venus and Jupiter are neighbors in the sky all week. At 7 a.m., Jupiter is about two finger-widths below the much brighter Venus, about a fist and a half above the south-southeast horizon. As the days go by, Venus will be moving down and to the left, passing Jupiter this weekend.
Tuesday: Let’s review three important sets of three cats. There’s Josie, Valerie, and Melody of Josie and the Pussycats. Felix, Tom, and Sylvester from old time cartoons. And, if you want to get away from the mind-numbing effects of television, there’s Leo the lion, Leo Minor, and Lynx in the night sky. Leo is by far the most prominent of these three constellations. Its brightest star called Regulus is nearly four fists above the east-southeast horizon at 11 p.m., just to the right of the Moon. The backwards question mark-shaped head of Leo is above Regulus and the trapezoid-shaped body is to the left of it. Leo Minor consists of a few dim stars right above Leo. Pretty wimpy. The long dim constellation called Lynx spans from just above Leo Minor to nearly straight overhead. You and fellow stargazers won’t need to wear a long tail or ears for hats to enjoy these stellar cats.
Wednesday: Mars is four and a half fists above the southwest horizon at 6 p.m.
Thursday: Do you see a hunter when you look at Orion, four fists above due south at 9 p.m.? The bright reddish star Betelgeuse and Bellatrix, the bright star one fist to the right of it are the broad shoulders of the hunter. The bright bluish star Rigel and Saiph, the bright star to the left of Rigel, represent the knees. The Maya saw the equilateral triangle formed by Rigel, Saiph, and the left-most belt star as the “Three Stones of the Hearth”. The Orion Nebula is in the center of the hearth and it represents the flame, called K’ak.
Friday: 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.
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.