Thursday, May 28, 2015

The Ellensburg WA sky for the week of 5/30/15

Saturday: In 1979, the group Foreigner recorded the song “Head Games”. They could have been singing about the constellations Hercules and Ophiuchus when they said “head games, it’s just you and me baby, head games, I can’t take it anymore” because the heads of these two constellations have been right next to each other in the nighttime sky for all of human history. And just to make it easy for you, a star that bears an Arabic name that means “the head” represents each head. In Hercules, it's Ras Algethi (head of the kneeler); in Ophiuchus, Ras Alhague (head of the serpent charmer). At 11 p.m., Ras Alhague, the brighter of the two, is a little more than four fists held upright and at arm’s length above the southeast horizon. Ras Algethi is about a half a fist to the upper right of Ras Alhague.

Sunday: Saturn is less than a fist to the lower left of the nearly full moon at 10 p.m.

Monday: The month of June is named after Juno, the queen of the Roman gods and the mythological protector of the Roman state. In ancient Rome, the month began when the crescent moon was first seen in the evening sky from Capitoline Hill in Rome. If we still started months this way, June would have started a couple of days ago, right after the moon was last new. Celebrate the first sunset in June by actually watching it… and then keeping your gaze fixed on the west-northwest horizon until it is dark enough to see Venus, Jupiter, and the star Regulus in a line pointing away from the Sun. At 9:30 p.m., Venus is about two and a half fists above the west horizon, Jupiter is two fists to the upper left of Venus, and Regulus is a fist and a half to the upper left of Jupiter.

Tuesday: Astronomers using a radio telescope in Australia recently discovered the source of fleeting radio signal bursts that had been a mystery for 17 years. And they didn’t have to probe the depths of deep space. They only had to probe the depths of… the observatory kitchen. It turns out the signal came from opening the microwave door prematurely. Read more about The Microwave Emission here: Sheldon Cooper used similar methods of science when he discovered a can opener instead of magnetic monopoles in the season three premiere of The Big Bang Theory

Wednesday: Cygnus the swan flies tonight. Deneb, the brightest star in the constellation, whose name means “tail” in Arabic, is two fists above the northeast horizon at 10 p.m. Cygnus’ wings make a vertical line one half a fist to the right of Deneb. Its head, marked by the star Albireo, is two fists to the right of Deneb. While Deneb is at the tail of Cygnus, it is at the head of the line of bright stars. It is 160,000 times more luminous than the Sun making it one of the brightest stars in the galaxy. It does not dominate our night sky because it is 2,600 light years away, one of the farthest naked eye stars. If Deneb were 25 light years away, it would shine as bright as a crescent moon. Compare that to Vega, which is 25 light years away. Vega is three and a half fists above the east-northeast horizon at this time.

Thursday: It’s time for your Thursday morning binocular challenge. At 4 a.m. (I told you it was a challenge), look due east at the horizon. Now move your binoculars up about one and a half fields of view or 10 degrees. You should see a small equilateral triangle of three “stars” with similar brightness. The upper right point of light is the planet Uranus.

Friday: Mars is too close to the setting Sun to be seen from Earth. So take this opportunity to see images of the setting Sun from Mars at Martian dust particles in the direction of the setting Sun scatter blue light forward and form a blue ring around the Sun.

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

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