Wednesday, August 20, 2014

The Ellensburg sky for the week of 8/30/14

Saturday: Curriculum review: Can you pick out a triangle made of three bright objects in the night sky? At 9 p.m., the moon, Mars, and Saturn make a triangle low in the southwest sky. Mars is about a half a fist below the moon and Saturn is about a half a fist to the right of the moon.

Sunday: 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.

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: “I’m a little teapot, short and stout. The galactic center, I pour it out.” (I’m a Little Teapot, astronomy version, 2014.) 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.

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 is two fists above the east horizon at 5:45 a.m. Venus is a bit more of a challenge to spot, only a half a fist above the east-northeast horizon.

Friday: 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.


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.

The Ellensburg sky for the week of 8/23/14

Saturday: School starts next week so it is time for a little geometry review. A square is a four-sided figure with four equal sides and four right angles. Go outside at 10 p.m. tonight with notebook in hand to sketch one. The Great Square of Pegasus is balancing on its corner two fists held upright and at arm’s length above due east. The top corner of the square is two fists above the bottom corner. The other two corners are to the left and right of the line segment connecting the top and bottom corners.

Sunday: Geometry review, part 2. Go outside at 10 p.m. tonight with notebook in hand. (Good teaching involves a little repetition.) 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: Tonight’s moon is new. That means you won’t be able to see it. But that does not mean it doesn’t exist. Contrary to the belief of toddlers and immature politicians, just because you can’t see something doesn’t mean it doesn’t exist. (Note a double negative statement followed by a triple negative statement. I’m not unsorry about that.) Now, back to the science. What would happen to the earth if the moon really didn’t exist? In last summer’s blockbuster Oblivion, aliens destroy the moon and Tom Cruise survives. But the long-term effects on the earth would be devastating to life as we know it. The moon stabilizes the spin axis of the earth keeping the seasons fairly uniform over time. For more information on what would happen to the earth if the moon were destroyed, go to http://goo.gl/jM1d4. For more information on Thomas Cruise Mapother IV, go to http://en.wikipedia.org/wiki/Tom_Cruise.

Tuesday: Saturn and Mars are brightness twins, fraternal twins, of course. The red planet Mars is one fist above the southwest horizon at 9 p.m. The yellowish Saturn is less than a half a fist to the upper right of Mars.

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 25th 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 numbered 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: The brightest planet Venus is a half a fist above the east-northeast horizon at 5:30 a.m. Jupiter, the second brightest planet, is about a fist to the upper right of Venus.

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. For up to date information about the night sky, go to https://nightsky.jpl.nasa.gov/planner.cfm.

Wednesday, August 13, 2014

The Ellensburg sky for the week of 8/16/14

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: Venus and Jupiter are one fist above the east-northeast horizon at 5:30 a.m. Venus is the brighter of the two, less than a pinky thickness above Jupiter. By tomorrow morning, they will have flip flipped and be even closer together in the sky. As the days go by, Venus will move toward the horizon.

Monday: At 9 p.m., Mars is one and a half fists above due southwest. Saturn is a half a fist to the upper left of Mars. Midway between the two is the star with the name of the day: Zubenelgenubi, also knows as the southern claw. This star’s name is a good example of how the constellation shapes have changed over time. Zubenelgenubi is now part of Libra. But Libra and Scorpius the scorpion used to be one constellation with Zubenelgenubi and Zubeneschamali (northern claw) making up the scorpion’s large appendages.

Tuesday: 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.

Wednesday: The Pleiades is about one fist above the east-northeast horizon at midnight.

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 if there is life anywhere else that we are related to. The Mars Science Laboratory landed on Mars last summer 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. NASA and the European Space Agency are planning a trip to study Europa, the Jovian moon with an ice-covered ocean. 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: 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. For up to date information about the night sky, go to https://nightsky.jpl.nasa.gov/planner.cfm.

Wednesday, August 6, 2014

The Ellensburg sky for the week of 8/9/14

Saturday: The Perseid meteor shower hits its peak late for the next few nights with Tuesday being the peak of the peak. 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. 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. For tips about optimizing your viewing this year, go to http://goo.gl/8vp1mH. 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.

Sunday: It’s another bird. No, it’s another plane. No, it’s another super moon, the largest super moon of the year. The moon has been very close to perigee for the past two full moons and is again this full moon. At perigee, the moon is at its closest to the earth. (After all, that’s what perigee means.) And when items are closer to us, they appear larger. So a super moon is really a close moon. Maybe the close talker on the show “Seinfeld” should have been called the super talker.

Monday: Mars is one and a half fists above due southwest at 9 p.m. Saturn is a fist to the upper left of it.

Tuesday: Venus and Jupiter move towards each other in the morning sky for the next week. This morning, Venus is a little more than a half a fist above the east-northeast horizon and Jupiter is just barely above the horizon. As the days go by, Jupiter moves upward and Venus moves down toward the horizon.

Wednesday: 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.

Thursday: Arcturus is two and a half fists above due west at 10:30 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.

Friday: Hercules stands almost directly overhead at 9:00 this evening. Four moderately bright stars form a lopsided square that represents his body, while his head points southward.


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.

Friday, August 1, 2014

The Ellensburg sky for the week of 8/2/14

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 early next week. But you should see increased meteor activity later this week 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

Sunday: Four in a row will not win in poker. But it makes a winning target in the night sky.  From sunset until about 10:30, Spica, Mars, the moon, and Saturn line up in the southwestern sky. At 10 p.m., the moon is due southwest. Saturn is less than a half a fist to the upper left of the moon. Mars is about a fist to the lower right of the moon and Spica is more than a fist to the lower right of Mars.

Monday: The bright star Vega is nearly straight overhead at 11 p.m.

Tuesday: 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.

Wednesday: School starts in about a month so it is time to start reviewing your geometric shapes. Let’s start with the right triangle that is a fist above the west-southwest horizon at 10 p.m. The bluish star Spica is at the right angle, in the lower left corner of the triangle. Saturn is a half a fist above Spica and Mars a fist to the right of Spica.

Thursday: 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/L9ppJf.

Friday: Venus is a little less than a half a fist above the east-northeast horizon at 5 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.