Friday, April 26, 2013

The Ellensburg sky for the week of 4/27/13


Saturday: 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 three fists held upright and at arm’s length above the south horizon at 1 a.m. It is two fists 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, and 4/15/13, you know that Saturn was also in opposition on those dates. Thus, it is in opposition about 13 days later each year. 13 days is about one twenty-ninth of a year. This implies that it takes Saturn about 29 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.

Sunday: Many ancient philosophers thought the pattern of movement in the heavenly bodies represented a “musica universalis” ore “universal music”. For example, Pythagoras, the right triangle guy, hypothesized that the Sun, Moon, and planets emitted their own characteristic hum based on their orbital motion. Of course we now know that it not the case. But that does not mean astronomy and music are unrelated. At noon Pacific Daylight Time today, Italian pianist and composer Giovanni Renzo will give an online Cosmic Concert with music to accompany beautiful pictures and videos of the night sky. Go to http://goo.gl/YTSgO for more information about the concert and http://goo.gl/QUuLI for a live stream of the concert.

Monday: How many stars can you see in the constellation Leo the lion? This week, you can help answer that question. The organization called GLOBE at Night is looking for people all over the world to count how many stars they can see in one of three constellations. Participants use star charts found at http://www.globeatnight.org/ to observe Leo, Orion, or Crux and compare what they see to the charts. After making the observations, participants can go to the website and add their findings to those of thousands of other observers. The main goal of GLOBE at Night is to research the pattern of light pollution across the globe. A secondary goal is to increase interest in observing and awareness of the night sky. You can find Leo, the best observing choice for Ellensburg, five fists above the southwest horizon at 10 p.m. Regulus, one of the brightest stars in the sky, is at the bottom of the constellation, just over four fists above the southwest horizon.

Tuesday: 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 11 p.m. Crater is just to the right of Corvus.

Wednesday: Winter must be over because the winter constellations are becoming less visible. Orion is setting due west starting at about 9 p.m. At this time, Orion’s belt is a little more than half a fist above the west horizon and Betelgeuse is nearly two fists above the west horizon. By mid-May, Orion will be lost in the glare of the Sun.

Thursday: Do people think you have a magnetic personality? The star Cor Caroli understands how you feel. Cor Caroli has one of the strongest magnetic fields among main sequence stars similar to our Sun. This strong magnetic field is thought to produce large sunspots that cause the brightness of Cor Caroli to vary. Cor Caroli is nearly straight overhead at 10:30 p.m.

Friday: Jupiter is two fists above the west horizon at 9 p.m.

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

Monday, April 15, 2013

The Ellensburg sky for the week of 4/20/13


Saturday: Regulus, the brightest star in the constellation Leo the lion is less than a fist held upright and at arm’s length above the moon at 9 p.m. They are midway up in the southern sky.

Sunday: Remember the old saying: April showers bring… meteors. The Lyrid meteor shower peaks tonight. The meteors appear to come from a point to the right of the bright bluish star Vega in the constellation Lyra the lyre. This point is about three fists held upright and at arm’s length above the east-northeast horizon at midnight tonight and close to straight overhead near dawn. The best time to look is just before dawn since that is when the radiant, or point from which the meteors appear to come, is high in the sky. This year, the Moon is in the waxing gibbous phase meaning it will be bright and be out for most of the night. Typically, this is one of the least interesting major meteor showers of the year. However, it is also one of the most unpredictable. As recently as 1982, there were 90 meteors visible during a single hour. In addition, the Lyrid meteor shower has historical interest because it was one of the first ones observed. Chinese records say “stars fell like rain” in the shower of 687 B.C. As your Mother might say, dress warm and sit in a comfortable chair for maximum enjoyment. Meteors are tiny rocks that hit the Earth and burn up in the atmosphere.

Monday: You know Metis and Thebe and Adrastea and Amalthea. Io and Ganymede and Callisto and Europa. But do you recall? There are 67 Jovian moons in all. (As of July 2012.) Less than 50 years ago, Jupiter was thought to have only 12 moons. But, astronomers are red-nosed with delight that the advent of supersensitive electronic cameras has caused the number of discovered moons to rapidly increase. Jupiter’s 67 moons range in size from Ganymede, with a diameter of 5,262 kilometers, to S/2002 J12 and S/2003 J9, with a diameter of only one kilometer. Our moon has a diameter of 3,475 kilometers. (One kilometer is 0.62 miles.) Saturn is second place in the moon race with 62. Uranus is next with 27. Then comes Neptune with 13, Mars with 2, and Earth with 1. Even dwarf planets have moons. Pluto has 5, Eris has 1, and Haumea has 2. Eris is an outer solar system object that was discovered in 2005 and named in September of 2006. Because astronomers thought it was larger than Pluto, people called it the tenth planet for a while. (More recent measurements show Eris to be a little smaller than Pluto.) Haumea, the newest dwarf planet with a moon, was discovered in 2004 and officially named a dwarf planet on September 17, 2008. Jupiter, the “mooning” champ, is a half a fist above the west horizon at 9 p.m. Go to http://goo.gl/Xkoeq for more information about Solar System moons.

Tuesday: Avast ye matey. Swab the poop deck. Pirates love astronomy. In fact, the term “poop” in poop deck comes from the French word for stern (poupe) which comes for the Latin word Puppis. Puppis is a constellation that represents the raised stern deck of Argo Navis, the ship used by Jason and the Argonauts in Greek mythology. Argo Nevis was an ancient constellation that is now divided between the constellations Puppis, Vela and Carina. The top of Puppis is about a fist and a half to the left of the bright star Sirius in the south-southwest sky at 9 p.m. Rho Puppis, one of the brightest stars in the constellation, is about one and a half fists above the south-southwest horizon at this time.

Wednesday: Jupiter is two and a half fists above the west horizon at 9 p.m.

Thursday: Tonight’s full moon is called the Full Pink Moon because it marks the appearance of moss pink, one of the first spring flowers.

Friday: Saturn is one and a half 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.

Thursday, April 11, 2013

The Ellensburg sky for the week of 4/13/13


Saturday: Do you like clusters? Candy clusters? Data clusters? The German band Cluster? Tonight, the moon shows that it likes star clusters because it is between two of them at 9 p.m. The V-shaped Hyades cluster is less than a half a fist held out at arms length to the left of the moon and the more compact Pleiades is a little more than a half a fist to the right of the moon. Containing over 300 stars, the Hyades cluster is about 150 light years away and 625 million years old. The Pleiades Cluster has over 1000 stars and much younger. Compared to our 5 billion year old Sun, the 100 million year age of the Pleiades is infant-like.

Sunday: Sure Jupiter is the brightest point of light in the night sky this evening. But did you know you can also see it during the day? Today is a good day to try. You’ll need binoculars and the moon. First, find the waxing crescent moon five fists above the southeast horizon at 2 p.m. Aim your binoculars so the moon is near the bottom of your field of view. Jupiter will be in about the middle of your field of view. If the sky is completely cloud-free and steady, you may be able to see Jupiter with the naked eye. Hold two fingers out at arm’s length. Rotate them sideways and place them right above the moon. Jupiter will be right above your fingers. For more information about other celestial objects visible during the day, go to http://goo.gl/yMW12.

Monday: The nighttime stars take little more than an instant to rise. The Moon takers about two minutes to rise. That’s absolutely speedy compared to the constellation Virgo which takes four hours to rise. The first star in Virgo rises at 4:30 in the afternoon today. Spica, the brightest star in the constellation, rises at 7:30. By 9 p.m., Spica is a fist and a half above the southeast horizon.

Tuesday: The Boys of Summer have started their season. The stars of winter are ending theirs. At 10 p.m., four of the brightest wintertime stars have either set or will soon be setting. Sirius is about a half a fist above the west-southwest horizon. Rigel has set. The red giant Betelgeuse is a fist and a half above the west horizon. And Aldebaran is a fist above the west-northwest horizon.


Wednesday: The Lyrid meteor shower peaks next week. But there will be increased meteor activity for the next two weeks in the vicinity of the constellation Lyre. The meteors appear to come from a point to the right of the bright bluish star Vega in the constellation Lyra the lyre. This point is about three fists above the east-northeast horizon at midnight and close to straight overhead near dawn.

Thursday: Tonight’s first quarter moon is in the constellation Cancer the crab. At 10 p.m., the Beehive cluster is less than a fist above the moon. (See, I told you the moon liked star clusters.) The Beehive cluster, also called Praesepe, is an open star cluster of about 600 stars, all about 600 light years from Earth.

Friday: Saturn is less than one fist above the west-southwest horizon at 6 a.m.

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

Wednesday, April 3, 2013

The Ellensburg sky for the week of 4/6/13


Saturday: Some people in town today for the Yakima River Canyon Marathon may be looking for a little running inspiration. While nothing can take the place of a 20+ mile long run for marathon preparation (I know), certain objects in the night sky are inspiring. In the Bible, Job specifically mentions the star Arcturus, or the bear keeper, to his friend as a sign of God's majesty. He describes God as that "Which maketh Arcturus, Orion, and Pleiades, and the chambers (constellations) of the south" (Job 9:9, King James Version). Whatever your religious beliefs, it is clear that Job was impressed with this very bright star. See the star that inspired Job about one and a half fists held upright and at arm’s length above the east horizon at 9 p.m.

Sunday: If you ran far yesterday, you don’t want to stay up late looking at the stars. So do something during the day that will help you and other night sky enthusiasts: make sure your outdoor light fixtures are shielded or at least facing down. This will cut down on light pollution, stray light that obscures the stars, and it will help you celebrate the start of International Dark Sky week. Go to http://goo.gl/w6Hi7 for more information on how to do an outdoor lighting audit and get more information about International Dark Sky week.

Monday: Jupiter is three fists above the west horizon at 9 p.m.

Tuesday: The Virtual Messier Marathon I described in last week’s column has been moved to today at 11 a.m. Pacific Daylight Time. See astronomers find, show, and talk about interesting celestial objects. For more information, go to http://goo.gl/rDpyl. I noticed that none of my readers went to this link last week so now is your chance. (See, I’m checking up on you.)

Wednesday: Tonight’s moon is new. Don’t bother looking for it. The new moon is the phase where the moon is directly between the Earth and the Sun. Hence the side of the moon facing Earth is not receiving any sunlight and cannot be seen. The new moon is not a big deal this month. But, May 10, the new moon will be covering most of the Sun leading to an annular solar eclipse in some parts of the world such as Australia and the Solomon Islands. An annular solar eclipse occurs when the Moon, as seen from Earth, is relatively far from Earth in its orbit and not large enough to cover the Sun even though they are nearly perfectly lined up. Instead, there is bright ring or annulus around the Moon. The resulting eclipse is called an annular solar eclipse because of this ring.

Thursday: You probably didn’t know this but several British New Wave bands were really into astronomy. Take the band “Dead or Alive” (please). The original lyrics to their song “You Spin my Round (Like a Record) were thought to be: “ You spin me right round, baby, right round, like the Whirlpool Galaxy, right round, round, round.” (Well, that’s what I thought them to be.) The Whirlpool Galaxy was the first galaxy observed to have a spiral shape. Since then, astronomers have discovered many galaxies, including our own Milky Way Galaxy, have a spiral shape. Go to http://www.spacetelescope.org/images/heic0506a/ for more information about the Whirlpool Galaxy. Go to your small telescope to find the Whirlpool Galaxy in the night sky. It is in the constellation Canes Venatici, the hunting dogs. At 10 p.m., find Alkaid, the end star of the Big Dipper handle, five fists held upright and at arm’s length above the northeast horizon. The Whirlpool Galaxy is two fingers to the upper right of Alkaid.

Friday: Saturn is a little more than a 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.