The Ellensburg Sky for the week of 9/1/12

Saturday: Geometry review: part 3. School starts this week so it is time to continue our little geometry review from last week. Did you forget last week’s lesson? Well, go to the litter box, dig out last Saturday’s paper and review it. Then go outside at 9 p.m. with notebook in hand. Ready? A square is a quadrilateral with four sides of equal length and four right angle corners. A good example in the sky is the Great Square, an asterism (group of stars) consisting of three stars from the constellation Pegasus and one star from the constellation Andromeda. At 9 p.m., the bottom of the Great Square is two fists held upright and at arm’s length above due east.

Sunday: There is a lot to see at the Kittitas County Fair. But there is not a lot to see in the sky when you are at the fair because the fair lights, which are fairly bright, obscure most celestial objects. The bluish star Vega is one of the few objects bright enough to be seen. As you are finishing your rides at 10 p.m., look for Vega nearly straight overhead.

Monday: Labor Day was the brainchild of labor unions and is dedicated to American workers. The first Labor Day was celebrated in 1882. The Greek mythical hero Hercules probably wished there was a Labor Day to commemorate his work. As punishment for killing his family while he was temporarily insane, he had to perform twelve nearly impossible tasks such as killing monsters or stealing things from deities. Humm. Maybe we shouldn’t commemorate his labors. But we can enjoy his constellation. The keystone asterism representing the body of Hercules is six fists above the west horizon at 10 p.m. For more information about the Labors of Hercules, go to http://goo.gl/ozVF5.

Tuesday: Saturn is one fist above the west-southwest horizon and about a half a fist above Spica. Mars is one fist to the left of Saturn.

Wednesday: The calendar says summer is nearing an end. School starting today says summer is nearing an end. The summer triangle in the sky begs to differ as it is still high in the sky. Vega, the brightest star in the triangle, is a little bit west of straight overhead at sunset. Deneb is a little bit east of straight overhead and Altair is five fists above the south horizon.

Thursday: Jupiter rises at about 11:30 p.m. and is about a half a fist above the northeast horizon at midnight. By 6 a.m., Jupiter is six fists above the southeast horizon. At this time, Venus is three fists above the east horizon.

Friday: In the movie The Terminator, Arnold said “Hasta la vista, baby”. Tomorrow you can join NASA scientists and many other people around the world in saying “Hasta la vista, Vesta”. The probe known as Dawn has studied the asteroid Vesta for the past year. Soon it will head over to the dwarf planet Ceres. Before it goes, Dawn scientists and engineers will host a Google+ Hangout from noon-2:00 p.m. Pacific Daylight Time. You can also get mission updates on Facebook or Twitter. For more information, go to http://goo.gl/fKorW.

The positional information in this column about stars and planets is typically accurate for the entire week.

The Ellensburg sky for the week of 8/25/12

Saturday: Let’s all sing along with that fabulous oldie: Blue Moon.

Blue moon, you see it up in the sky.

The second moon in a month.

But that description’s a lie.

The term “blue moon” has had a number of meanings throughout history. In the earliest meaning, blue moon means never as in “The astronomy columnist’s next invitation to a Daily Record party will happen when the moon turns blue.” By the nineteenth century, astronomers noticed that the moon really does turn blue. For example, when the Indonesian volcano Krakatoa erupted in 1883, its dust turned the moon blue for two years. Thus, once in a blue moon came to mean “infrequent” rather than “never”. Most months have only one full moon and most seasons have only three full moons. The Maine Farmer’s Almanac lists the third of four full moons in a season as the blue moon. In 1946, James Hugh Pruett of Eugene, Oregon misquoted the Maine Farmer’s Almanac in a Sky and Telescope magazine article. He wrote that the blue moon was the second full moon in a month, which is not how the Maine Farmer’s Almanac defined it. For years after that, Sky and Telescope magazine as well as other media outlets used the incorrect description. The moral of the story: Always carefully read the Maine Farmer’s Almanac.

Sunday: School starts next week so it is time for a little geometry review. Go outside at 10 p.m. tonight with notebook in hand. Ready? A triangle is a polygon with three corners and three line segments as sides. A good example is the Summer Triangle made up of the bright stars Vega, Deneb and Altair. Vega, the brightest star in the triangle is a little bit west of straight overhead. Deneb is a little bit east of straight overhead and Altair is five fists held upright and at arm’s length above the south horizon.

Monday: Now that you know the general definition of a triangle, it is time for some specifics. A right triangle. At 8:30 p.m., Mars, Saturn, and the star Spica make a right triangle about one fist above the west-southwest horizon.

Tuesday: At 6 a.m., Venus is three fists above the east horizon and Jupiter is five and a half fists above the southeast horizon.

Wednesday: The Ellensburg Rodeo is a “Top-25” rodeo. What does it take to be a “Top-25” star? There are many ways to rank stars. The most obvious way for a casual observer to rank stars is by apparent brightness. The apparent brightness is the brightness of a star as seen from Earth, regardless of its distance from the Earth. Shaula (pronounced Show’-la) is the 25^th brightest star in the nighttime sky as seen from Earth. It represents the stinger of Scorpius the scorpion. In fact, Shaula means stinger in Arabic. Shaula has a visual brightness rating of 1.62. Sirius, the brightest star has a visual brightness rating of -1.46. (Smaller numbers mean brighter objects.) The dimmest objects that can be seen with the naked eye have a visual brightness rating of about 6. There are approximately 6,000 stars with a lower visual brightness rating than 6 meaning there are 6,000 stars visible to the naked eye. Shaula is a blue sub-giant star that radiates 35,000 times more energy than the Sun. It is 700 light years away making it one of the most distant bright stars. Shaula is a challenge to find because it never gets more than a half a fist above the horizon. Look for it tonight about a half a fist above the south horizon, a little bit west of due south, at 8:30.

Thursday: Tonight’s moon is full making it difficult to see dim objects in the sky because of the sky glow. While that might make you initially feel blue, you should really feel happy because there is so much to see on the moon itself. In fact, the lunar crater called Tycho is best seen during a full Moon. Tycho was formed about 109 million years ago when an asteroid struck the Moon, leaving a crater over 50 miles in diameter and ejected dust trails that radiate out hundreds of miles in all directions. For more lunar highlights and a basic lunar map, go to http://goo.gl/eJn5p, a resource of the Night Sky Network.

Friday: “I’m a little teapot, short and stout. The galactic center, I pour it out.” (I’m a Little Teapot, astronomy version, 2011.) Despite its great size and importance, the center of our Milky Way galaxy and its giant black hole remains hidden to the naked eye behind thick clouds of gas and dust. By plotting the orbits of stars near the middle of the galaxy, astronomers have determined that the black hole’s mass is equal to about 4.5 million Suns. While you can’t see the actual galactic center, you can gaze in the direction of the center by looking just to the right of the teapot asterism in the constellation Sagittarius. This point is about one fist above the south-southwest horizon at 9 p.m.

The positional information in this column about stars and planets is typically accurate for the entire week.

The Ellensburg sky for the week of 8/18/12

Saturday: Sometimes you find a quarter on the ground. Maybe you find a dollar in the lining of your jacket. But how often do you find a galaxy in a well-known part of the sky? The Hubble Space Telescope discovered a face-on spiral galaxy in the Coma Cluster of galaxies about 320 million light years away. This galaxy, called NGC 4911, contains regions of gas and dust as well as glowing newborn star clusters. The Coma Star cluster is in the constellation Coma Berenices, found two and a half fists held upright and at arm’s length above the west horizon at 9 p.m. For more information about this newly discovered galaxy, plus a zoomable image, go to http://goo.gl/5OXUX.

Sunday: Need a caffeine pick-me-up? Make it a double. Need an astronomy pick-me-up? Make it a double-double. Find Vega, in the constellation Lyra the lyre, nearly straight overhead at 11:00 tonight. Less than half a fist to the east (or left if you are facing south) of the bright bluish star Vega is the “star” Epsilon Lyra. If you look at Epsilon Lyra through binoculars, it looks like two stars. If you look at Epsilon Lyra through a large enough telescope, you will notice that each star in the pair is itself a pair of stars.  Each star in the double is double. Hence, Epsilon Lyra is known as the double-double. The stars in each pair orbit a point approximately in the center of each respective pair. The pairs themselves orbit a point between the two pairs.

Monday: Do you miss Olympic beach volleyball already? I know I do. (Oops, is my wife reading this?) In order to keep this fine sport on your mind until Rio 2016, the southern sky offers a giant bathing suit bottom to look at. The constellation Capricornus is two fists above the south-southeast horizon at 11 p.m. Many ancient cultures called this set of stars a sea goat. But our celebrity obsessed culture notes the triangle-shaped constellation looks like the bottom section of a swimsuit. If People magazine named the constellations, this one might be called Kardashian Formal wear.

Tuesday: The moon, Spica, Mars, and Saturn can nearly fit into a wide-angle binocular field of view tonight when they form a crooked rectangle. Mars is the left corner of the rectangle, Saturn is at the top, and Spica is at the lower right.

Wednesday: The 5:30 a.m. sky is crowded with planets. Let’s start with the hardest to find first. Mercury is a half a fist above the east-northeast horizon. Venus, the brightest point of light in the sky, is three fists above due east. Jupiter is five fists above the east-southeast horizon.

Thursday: Have you ever gone to a family reunion, looked around and asked, “How in the world are we related to each other?”. Astronomers look around the Solar System and wonder the same thing. The Mars Science Laboratory landed on Mars at the beginning of August to investigate whether it ever had conditions favorable for life. The Cassini Mission continues to study the plume of complex organic chemicals streaming from Saturn’s moon Enceladus. And many astronomers consider the methane haze in the atmosphere in Saturn’s moon Titan similar to that of the early Earth. To learn more about the search for life in the Solar System and beyond, go to http://goo.gl/ewtfr.

Friday: Antares, sometimes called the “heart of the scorpion” because it is a red star in the middle of Scorpius, is a half a fist below the moon at 9 p.m. They are low in the south-southwest sky.

The positional information in this column about stars and planets is typically accurate for the entire week.

The Ellensburg sky for the week of 8/11/12

Saturday: The Perseid meteor shower hits its peak tonight and early tomorrow morning. The meteors appear to come from a point just below the W of the constellation Cassiopeia. This point is about two and a half fists held upright and at arm’s length above the northeast horizon at 11 p.m. By dawn, this point is about seven fists above the northeast horizon. With dark skies, you can see up to 100 meteors per hour in the late night and early morning hours all week. Unfortunately, the early morning waning crescent moon will obscure all but the brightest fireballs. As your Mother might say, dress warm and sit in a comfortable chair for maximum enjoyment. These meteors are sand to pea-sized bits of rock that fell off of Comet Swift-Tuttle. They are traveling about 40 miles per second as they collide with the Earth and burn up in the atmosphere. For more tips about the Perseid meteor shower, go to http://goo.gl/CC63c.

Sunday: The Moon is about halfway between Venus and Jupiter this morning. The brighter Venus is a fist and a half to the lower left and Jupiter is a fist to the upper right of the Moon.

Monday: Have there been a lot of crimes in our part of the galaxy? Perhaps because there have been Solar System line-ups two days in a row. At 9:30 p.m., the star Spica is a half a fist above the west-southwest horizon. Mars is about two fingers above Spica and Saturn is a half a fist above Spica. All three objects have a similar apparent brightness making it more difficult to identify the perpetrator.

Tuesday: Many big city dwellers never see the milky white, nearly continuous band of stars known as the Milky Way. As cities grow and add more lights, it has become harder to see the bulk of the Milky Way galaxy, our home in the universe. But, there are two easy ways to see the Milky Way. The first way is to look in the mirror. You are part of the Milky Way. The second way is to look from due north through the point straight overhead (called the zenith) to due south from 10:30 p.m. to 1 a.m. for the next two weeks. This is the time of year when the Milky Way is highest in the sky and away from the city lights on the horizon.

Wednesday: Mercury is about a half a fist above the horizon at 5:30 a.m. Even though Mercury is our second closest planetary neighbor, its proximity to the Sun makes it difficult to see most of the time. Luckily, it is a half a fist to the lower left of the Moon this morning giving us another marker to help us find it. It is also in a ling line with Venus and Jupiter.

Thursday: You think the Ellensburg wind is bad. Some of the Jovian planets have winds of over 1000 miles per hour. Jupiter and Saturn have belts of rapidly moving clouds that can be observed with back yard telescopes. To learn more about windy worlds, go to http://goo.gl/GLWAi.

Friday: Deneb is about seven fists above the east horizon at 10 p.m. When you look at Deneb, you are seeing light that left Deneb about 1,800 years ago.

The positional information in this column about stars and planets is typically accurate for the entire week.

The Ellensburg sky for the week of 8/4/12

Saturday: It’s a moonless August morning. The first remnant of dawn has not appeared yet. Suddenly, you notice a large softly radiant pyramid of light in the east sky. The base of this ghostly triangle is along the east horizon and the peak stretches two or three fists held upright and at arm’s length above the horizon about two hours before sunrise. Don’t be scared. It’s not really a ghost. It is an effect called the zodiacal light. This light comes from sunlight reflecting off dust grains in our solar system. The effect is the most visible when the band of constellations called the zodiac makes a steep angle with the horizon. You need a clear dark sky with no haze or light pollution to see the zodiacal light. At its brightest, the zodiacal light rivals the light of the central Milky Way. This is one of the best times of year to see the zodiacal light in the morning.

This is also one of the best times of the year to see meteors. The Perseid meteor shower peaks later this week.

Sunday: Saturn, Mars, and Spica make a small, nearly equilateral triangle about one fist above the west-southwest horizon this week.

Monday: Let’s all sing the galactic black hole monster song: “D is for dusty, that’s good enough for me. D is for dusty that’s good enough for me. D is for dusty that’s good enough for me. Oh dusty, dusty, dusty starts with D.” Astronomers know that spiral galaxies such as our own have super massive black holes in the center, black holes that are billions of times the mass of the Sun. They thought they got to be this massive by mergers where two galaxies collide and the gas, dust and black holes at the center of each colliding galaxy form a larger central black hole. But many distant galaxies show no signs of galactic mergers. Astronomers think the black holes at the center of these galaxies grew simply by snacking on the gas and dust that comes from supernova explosions and normal star formation. Just like the Cookie Monster gains weight by snacking on individual cookies rather than eating a cookie factory. Cookie crumbs, I mean dust, block your view of the center of our galaxy.  It is about one fist above due south at 10 p.m., between the constellations Sagittarius and Scorpius. For more information, go to http://goo.gl/GRrWa.

Tuesday: Arcturus is two and a half fists above due west at 11 p.m. This star, whose name means bear watcher, is the brightest in the sky’s northern hemisphere. It follows Ursa Major, the Great Bear, around the North Star. Arcturus is the closest giant star to Earth and is one of the few stars whose diameter can be measured directly.

Wednesday: Had the script been written a little differently for a well-known Robin Williams movie, we might have heard Mr. Williams shout, “Goooood Morning Orion the hunter”. Orion is typically thought of as a winter constellation. But, it makes its first appearance in the summer sky. The lowest corner of Orion’s body, represented by the star Saiph (pronounced “safe”), rises at 4:30 a.m., well before the Sun. By 5 a.m., Orion’s belt is about one fist above the east-southeast horizon.

Thursday: The two brightest points of light in the sky are hanging out together. At 5 a.m., Venus is about two and a half fists and Jupiter is about four fists above the east horizon.

Friday: The Perseid meteor shower hits its peak late for the next few nights. The meteors appear to come from a point just below the W of the constellation Cassiopeia. This point is about two and a half fists above the northeast horizon at 11 p.m. By dawn, this point is about seven fists above the northeast horizon. If you fall asleep or forget to set your alarm, you will be able to observe this shower from about 11 p.m. to dawn for the next three nights in about the same location in the sky. The Perseid shower is one of the longest lasting showers. With dark skies, you can see up to 100 meteors per hour in the late night and early morning hours all week. Unfortunately, the early morning waning crescent moon will obscure all but the brightest fireballs. As your Mother might say, dress warm and sit in a comfortable chair for maximum enjoyment. These meteors are sand to pea-sized bits of rock that fell off of Comet Swift-Tuttle. They are traveling about 40 miles per second as they collide with the Earth and burn up in the atmosphere. For more tips about meteor watching, go to http://goo.gl/6glPq.

The positional information in this column about stars and planets is typically accurate for the entire week.