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: http://goo.gl/Ftb04C. 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 http://goo.gl/kAEoOD.

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 http://goo.gl/08tRgw. 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 http://nightsky.jpl.nasa.gov/planner.cfm.

Thursday, May 21, 2015

The Ellensburg WA sky for the week of 5/23/15

Saturday: Jupiter is a little more than a half a fist above the Moon at 9 p.m.

Sunday: The constellation Aquila the eagle is starting its migration across the summer evening sky this month. Aquila, marked by its bright star Altair, rises to one fist held upright and at arm’s length above the east horizon at 11 p.m. Not all animal migrations are fully understood by scientists. We might be inclined to attribute bird migrations to instinct. This answer certainly did not satisfy the theologian C. S. Lewis. In his short work “Men Without Chests”, he wrote, “to say that migratory birds find their way by instinct is only to say that we do not know how migratory birds find their way”. In science (and theology), Lewis is telling us to look for real causes and not simply labels such as instinct. The cause for Aquila’s migration is the Earth orbiting the Sun. As the Earth moves around the Sun, certain constellations move into the evening sky as others get lost in the glare of the setting Sun.

Monday: Venus, Pollux, and Castor make a right triangle two fists above the west-northwest horizon at 10 p.m. tonight. You know what a right triangle is. You listened to your math teachers, right? They worked hard for less pay than their intellect would normally merit. Venus is the very bright point at the bottom of the triangle. Pollux is above Venus at the right angle.

Tuesday: Late spring and early summer is a good time to look for star clusters. Last week, you learned about M3, the third object cataloged by French astronomer Charles Messier over 200 years ago. One of the best clusters is the globular cluster in the constellation Hercules, also called M13. (Hummm. Guess what number that object is in Messier’s catalog.) Globular clusters are compact groupings of a few hundred thousand stars in a spherical shape 100 light years across. (For comparison, a 100 light year diameter sphere near out Sun would contain a few hundred stars.) The globular cluster in Hercules is six fists above the east horizon at 11 p.m. First find Vega, the bright bluish star about four fists above the east-northeast horizon. Two fists to the upper right of Vega is a keystone shape. Aim your binoculars at the two stars that form the uppermost point of the keystone. The globular cluster is one third of the way south of the uppermost star on the way to the rightmost star of the keystone. It looks like a fuzzy patch on the obtuse angle of a small obtuse triangle. If you don’t know what an obtuse angle is, you should not have told your teacher, “I’ll never need to know this stuff”.

Wednesday: While the NASA probe Dawn is off exploring the largest main-belt asteroid Ceres, you can explore the second largest asteroid Vesta. NASA has released Vesta Trek, a free web-based application that allows you to zoom in, “fly” over the surface, measure craters sizes, and see what Vesta looks like in different wavelengths of light. Go to http://goo.gl/97NxgF for more information about Vesta Trek and the Dawn mission.

Thursday: Good night little doggie. Procyon, the brightest star in Canis Minor, the little dog, is less than one fist above the west horizon at 10 p.m. Over the next couple of weeks, it will be too close to the setting Sun in the sky to be visible.

Friday: Saturn is almost two fists above the southeast horizon at 10 p.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 http://nightsky.jpl.nasa.gov/planner.cfm.

Wednesday, May 13, 2015

The Ellensburg WA sky for the week of 5/16/15

Saturday: The questions who, what, where, and when can only be asked with a “W”. At 11 p.m., the W-shaped constellation Cassiopeia is about two fists held upright and at arm’s length above due north. The middle star in the W was used as a navigation reference point during the early space missions. The American astronaut Gus Grissom nicknamed the star Navi, his middle name Ivan spelled backwards. After he died in the Apollo 1 fire, the star name was kept as a memorial.

Sunday: NASA’s Dawn space probe is closing in on the largest asteroid, Ceres. While it is important to send spacecraft to explore the asteroid belt, sometimes asteroid parts come to us. The light that bounces off the second largest asteroid 2 Pallas shows it is made of the same material as some rare dark stony meteorites that show signs of being altered by contact with water. These meteorites may have broken off 2 Pallas or a similar asteroid during the early Solar System. Go to http://goo.gl/0koPC0 for more information on 2 Pallas. For the next two months, 2 Pallas is in the constellation Hercules, visible with large binoculars or a small telescope.

Monday: In an old Saturday Night Live spoof advertisement for a turkey you can pump (http://goo.gl/OioQAr), Chris Rock sang, “The first turkey dinner was 1620. The pilgrims had it in the land of plenty.” But he could have just as easily say, “The light left Rasalgethi in 1620. The light now reaches us in the land of plenty.” Rasalgethi is a double star in the constellation Hercules that is almost 400 light years away. Its name is based on the Arabic words meaning “Head of the kneeler” because some views of Hercules depict him as a warrior kneeling down, perhaps resting after his twelve labors. You’ll find Rasalgethi exactly two fists above due east at 9:40 p.m.

Tuesday: Altair is about a half a fist above the east horizon at 11 p.m.

Wednesday: Give me an “M”. Give me a “3”. What does that spell? “M3.” “Big deal,” you say. It was a big deal to French comet hunter Charles Messier (pronounced Messy A). M3 was the 3rd comet look-alike that Messier catalogued in the late 1700s. M3 is a globular cluster, a cluster of over 100,000 stars that is 32,000 light years away. It is too dim to be seen with the naked eye but is fairly easy find with binoculars. First find Arcturus six fists above the southeast horizon at 11 p.m. Move your binoculars up a little so two stars of nearly identical brightness are in your field of view. When the top star is in the lower left part of your field of view, there should be a fuzzy patch near the center of your field of view. This is M3.

Thursday: Venus is about a fist to the upper right of the Moon at 10 p.m. In two nights, the Moon will have moved to be a little more than a half a fist underneath Jupiter.

Friday: Saturn is opposition tonight. That doesn’t mean that Saturn is a teenager. Opposition means that Saturn is on the opposite side of the Earth as the Sun. When an object is in opposition, it is at its highest point in the sky during the darkest time of the day. Thus, opposition is typically the best time to observe a planet. Saturn is about two and a half fists above due south at 1 a.m. It is about one fist above the southeast horizon at 10 p.m.
If you remember this column from 2/23/2008, 3/8/2009, 3/21/2010, 4/4/11, 4/15/12, 4/27/13, and 5/11/14, you know that Saturn was also in opposition on those dates. Thus, it is in opposition about 12 days later each year. 12 days is about one thirtieth of a year. This implies that it takes Saturn about 30 years to make one orbit around the Sun and get back in line with the same stars again. Saturn’s actual orbital period of 30 years matches this approximation very well.


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 http://nightsky.jpl.nasa.gov/planner.cfm.

Thursday, May 7, 2015

The Ellensburg WA sky for the week of 5/9/15

Saturday: Hit the road Mercury. And don’t you come back no more, no more. For a few weeks, Mercury has been hitting the road and moving away from the Sun in the sky. Today, Mercury is as far away from the Sun as it will get on the evening half of this cycle. This is known as its greatest eastern elongation. Yet, this distance does not translate into good viewing because Mercury will be very low in the sky. Mercury is about one fist held upright and at arm’s length above the west-northwest horizon at 9:00 p.m. Over the next few weeks, Mercury will move toward the Sun in the sky. After it passes in front of the Sun, it will appear in the morning sky by mid July.

Sunday: So you think your mother has problems on Mother’s Day because she had you as you as a child? Her mother issues can’t be as bad as Cassiopeia’s issues. First, she was chained to a chair for boasting about her beauty. Second, she has to revolve around the North Star night after night. Third, her daughter Andromeda was nearly killed by a sea monster. Look for poor Cassiopeia about one and a half fists above the north horizon at 10 p.m. Cassiopeia looks like a stretched out “W”.

Monday: Are you thirsty. I’ll wait while you get some water. I will NOT wait while Corvus the crow gets you some water. The Greco-Roman god Apollo made this mistake. He sent Corvus the crow to get some water in the cup known as Crater. Some figs distracted Corvus and he waited for them to ripen so he could eat them. When Corvus got back late, Apollo put Corvus and Crater in the sky with the gently tipping cup just out of the reach of the perpetually thirsty crow. Corvus is a trapezoid-shaped constellation about two fists above due south at 10 p.m. Crater is just to the right of Corvus.

Tuesday: Venus, the brightest point of light in the sky, is more than two fists above the west horizon at 9 p.m.

Wednesday: Jupiter is about four and a half fists above the southwest horizon at 9 p.m.

Thursday: This is a good time of the year to find the Big Dipper. It is nearly straight overhead at 10 p.m. The cup is to the west and the handle is to the east. You can always use the Big Dipper to find some other bright stars. First, follow the curve, or arc, of the Big Dipper down three fists into the southern sky. This is the bright star, Arcturus, the second brightest nighttime star we can see in Ellensburg. Next, continue on a straight line, or spike, another three fists down toward the south horizon to the star Spica. Spica is the tenth brightest nighttime star we can see in Ellensburg. It is known as the Horn Mansion, one of 28 mansions, or constellations, in the Chinese sky. You now know how to use the Big Dipper handle to “arc” to Arcturus and “spike” to Spica.

Friday: Dorothy from the Wizard of Oz clicked her heels and said, “There’s no place like home.” Future Dorothys may be clicking their heels to go to Kepler-186f, the first earth-sized planet orbiting a star in its habitable zone. This means there is a good chance for liquid water to exist on its surface. But it doesn’t mean it is habitable. The temperature of the planet depends greatly on its atmosphere. A thick atmosphere would mean a very hot planet like Venus in our own Solar System. For more information about Kepler-186f, go to http://goo.gl/zUZofJ.


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 http://nightsky.jpl.nasa.gov/planner.cfm.

Friday, May 1, 2015

The Ellensburg WA sky for the week of 5/2/15

Saturday: Today: As the rock group Journey once thought of singing, “Wheel in the sky keeps on turnin’. Know where the Dipper’ll be tomorrow.” Every night, the Big Dipper and Cassiopeia make a wheel in the sky that turns around the North Star in a counter clockwise direction. Every year on May 3 at 10 p.m., the Big Dipper is straight overhead and W-shaped Cassiopeia is low on the northern horizon. Every year on May 4 at 10 p.m., the Big Dipper is straight overhead and W-shaped Cassiopeia is low on the northern horizon. Every year on May 5 at 10 p.m., the Big Dipper is straight overhead and W-shaped Cassiopeia is low on the northern horizon. Every year on May 6 at 10 p.m., well, you get the idea. Of course, there are subtle charges in the position from night to night. Each northern constellation moves about one degree counter clockwise from one night to the next. But this is not going to change their position in the sky drastically over a few days. So if you know where the Big Dipper is tonight, you’ll also know where it will be tomorrow. If you are really struggling to understand this concept, Don’t Stop Believin’ in yourself.

Sunday: Sunday: Mother’s Day is a week away. What are you going to get her? Get her a Gem(ma). The star Gemma, also known as Alphekka, is the brightest star in the constellation Corona Borealis, the Northern Crown. Gemma, Latin for jewel is the central gemstone for the crown. It is four fists held upright and at arm’s length above due east at 10 p.m.

Monday: Mercury is one fist above the west-northwest horizon at 9 p.m. The much brighter Venus is somewhat near by, three fists above the west horizon.

Tuesday: The Eta Aquarid meteor shower peaks tonight and tomorrow morning. But since this meteor shower has a fairly broad peak range, there will be many more meteors than in the typical pre-dawn sky throughout the month of May. Meteor showers are named after the constellation from which the meteors appear to originate. The meteors appear to come from a point in the constellation Aquarius near the star Eta. This point is about one fist above the east horizon at 4 a.m. The waning gibbous moon will obscure the dimmer meteors. But you could be rewarded with some bright, fast meteors. The Eta Aquarid meteors slam into the Earth at about 40 miles per second. They often leave a long trail. The Eta Aquarid meteors are small rocks that have broken off Halley’s Comet. For more information about the Eta Aquarids, go to http://meteorshowersonline.com/eta_aquarids.html.

Wednesday: This weekend, celebrate Mother’s Day with the big mom of the sky, Virgo. Ancient Greeks and Romans associated this portion of the sky with their own goddess of the harvest, either Demeter (Greeks) or Ceres (Roman). Demeter was the mother of Persephone and Ceres was the mother of Proserpina. According to myth, each of these daughters was abducted causing their mothers great grief. The first star in Virgo rises in the afternoon. Spica, the bright bluish star in the constellation rises at 6:30 and is three fists above the south-southeast horizon at 10 p.m. Mars is about five times as bright and reddish. It is about a fist and a half to the upper right of Spica.

Thursday: Jupiter is five fists above the southwest horizon at 9:00.

Friday: Saturn is one fist above the southeast horizon at 11 p.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 http://nightsky.jpl.nasa.gov/planner.cfm