Friday, April 29, 2011

The Ellensburg sky for the week of 4/30/11

Saturday: Mother’s Day is just over 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 gem stone for the crown. It is four fists held upright and at arm’s length above due east at 10 p.m.

Sunday: You may be familiar with the 1980s New Zealand rock group “Crowded House”. They are making a comeback this week and rebranding themselves as “Crowded Sky” with a reworking of their 1987 hit “Don’t Dream it’s Over”. Here is a sample of the lyrics. “Hey now, hey now, don’t dream it’s over. Hey now, hey now, when the planets come in. They come, they come to fill the morning sky now. We know they won’t stay.” The planets Venus, Mercury, Jupiter and Mars are rising just before the Sun. This morning they are joined by the Moon. But the sky is illuminated by the soon-to-rise Sun so the only planet you’ll see is Venus, just above the east horizon at 5:15 a.m. Because all of the planets orbit the sun at different rates, the planets don’t stay in the same location with respect to the distant stars. The morning will not maintain its Crowded Sky. We know the planets won’t stay.

Monday: 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 term “new” comes from the moon seeming to be reborn with light every lunar cycle. Your calendar may list tomorrow as the new Moon. The moon is directly between the Earth and Sun early tomorrow morning making tomorrow the calendar day that the new Moon occurs. However, the night that starts at sunset this evening is the night of the new Moon.

Tuesday: Wake up before dawn for the next few mornings for a nice spring shower – a meteor shower. The Eta Aquarid meteor shower peaks just before dawn on Friday 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 week. 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. Although dawn is starting to light the sky, you could be rewarded with a few 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.

Wednesday: Saturn is four fists above the south-southeast horizon at 10 p.m.

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: 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 brightest star in the constellation rises at 6:30 and is two and a half fists above the southeast horizon at 10 p.m. Saturn is about a fist above it.

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

Wednesday, April 20, 2011

The Ellensburg sky for the week of 4/23/11

Saturday: You know Metis and Thebe and Adrastea and Amalthea. Io and Ganymede and Callisto and Europa. But do you recall? There are 63 Jovian moons in all. 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 63 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 61. Uranus is next with 27. Then comes Neptune with 13, Mars with 2, and Earth with 1. Even dwarf planets have moons. Pluto has 3, 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, was discovered in 2004 and officially named a dwarf planet on September 17, 2008. Saturn, in second place on the moon list, is three fists held upright and at arm’s length above the east horizon at 9 p.m. Go to http://www.skyandtelescope.com/observing/objects/planets/A_Guide_to_Planetary_Satellites.html for more information about moons.

Sunday: 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. Corvus got distracted by some figs 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.

Monday: “Water, water everywhere nor any drop to drink” is from The Rime of the Ancient Mariner. (No not Ichiro.) But is could be the slogan of our solar system. Astronomers used to think that the solar system was dry with earth being the only place to find water. It turns out that the solar system has an abundance of water, Comets are made of water ice. Some astronomers think they be the source of some, or even most, of Earth’s water. Jupiter’s Moon Europa has a crust of frozen water covering a large ocean containing more water than all of the Earth’s oceans. Even the Moon, thought to be dry as a bone, has frozen ice deep in its polar craters. Take a swim in the watery last quarter Moon this morning. Once you dry off, visit http://solarsystem.nasa.gov/yss/display.cfm?Year=2011&Month=4 to read more about solar system water.

Tuesday: 50 years ago this morning, Jupiter and Saturn were in line with the constellation Capricornus the sea goat. What does this mean for a person born on that day? Maybe they like swimming as symbolized by the water reference. Maybe they were raised in crowded conditions as symbolized by the two largest planets being in one constellation. Or maybe the location of the planets on the day you were born has nothing to do with what you become as an adult. Maybe you turn out to be a great person, loved by those close to you, because of the choices you make and the hard work that you do. That’s what I think. Take that, astrology!

Wednesday: Sirius, the brightest star in the nighttime sky, is one and a half fists above the southwest horizon at 8:30 p.m.

Thursday: Vega is one fist above the northeast horizon at 9:30 p.m.

Friday: Hydra the water snake rears its ugly head in the southwest sky at 10 p.m. First find Procyon. This bright star is two and a half fists above the west-southwest horizon. Next, find Saturn and Regulus right next to each other, five fists above the southwest horizon. Now, draw an imaginary line between Procyon and Regulus. Just below the midway point of that line, you should see a clump of stars that make the shape of a crooked house. This is the head of Hydra. The brightest star in the constellation, called Alphard, is three fists above the south horizon, midway between Regulus and the horizon. There are no other bright stars in the area. So it makes sense that the name Alphard means “the solitary one”.
As you may have noticed, Hydra is just below Corvus and Crater. Apollo put Hydra in the sky to keep Corvus from drinking the water from the cup.

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

Wednesday, April 13, 2011

The Ellensburg sky for the week of 4/16/11

Saturday: Saturn is a fist held out at arm’s length to the upper left of the Moon low in the southeast sky at 8 p.m. You may follow them throughout the night until they set at about 5 a.m. tomorrow morning. And if you can force yourself to stay awake or if you get up before sunrise or stay up very late any night this week, be on the lookout for meteors coming from nearly straight overhead near dawn. The Lyrid meteor shower is active this week.

Sunday: Do you like pop music? You don’t? So, so what. In the first draft of her biggest hit, the singer P!nk wrote “Waiter just took my full moon, and gave it to Jessica Simps”. Sit. Read about the April full Moon which occurs tonight. Some Native American tribes called the April full moon the full pink moon because its arrival coincided with the blooming of wild ground phlox, a pink wild flower.

Monday: Vega is two fists above the northeast horizon at 11 p.m.

Tuesday: 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. The middle section of Virgo will be marked by the planet Saturn for the next few months. Saturn is three fists above the southeast horizon at 9 p.m.

Wednesday: How many of you know your 12 nearest neighbors? I thought so. Why don’t you go out and meet them right now. I’ll wait. Yes, of course bring them cookies. No, not those stale ones you hate.
Are you back already? That means you didn’t really go out and meet your 12 nearest stellar neighbors, did you? Including the Sun, there are 12 stars within 10 light years of Earth. The most well known are the Sun (obviously); Proxima Centauri, the nearest star other than the Sun; Alpha Centauri, a bright binary star visible from the tropics and the Southern Hemisphere; and Sirius, the brightest star in the nighttime sky. Sirius is the largest and most luminous star in our neighborhood. It is one and a half fists above the southwest horizon at 9 p.m.

Thursday: Remember the old saying: April showers bring… meteors. The Lyrid meteor shower is typically active from tonight to April 27. 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 tonight and close to straight over head 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 light from the waning gibbous Moon will obscure the dimmer meteors. 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. This is typically one of the least interesting major meteor showers of the year with about 10-20 bright meteors per hour. 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.

Friday: Venus is less than a fist above the east horizon at 5:30 a.m.

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

Tuesday, April 5, 2011

The Ellensburg sky for the week of 4/9/11

Saturday: This month is Global Astronomy Month (www.gam-awb.org). Astronomers around the world want to reconnect people with the night sky, thus their slogan: One People, One Sky. For a summary of Global Astronomy Month events, click on “Events” at the top of the right-hand column. The feature event for this week, April 10-16, is Lunar Week. May I suggest OPTICKS, a live audio-video transmission performance between the Earth and the Moon? Amateur astronomers from around the world will bounce radio signals off of the Moon. These signals will be collected by a telescope in The Netherlands and webcast. The event starts tomorrow at 11 a.m., Pacific Daylight Time. For more information about lunar Week, go to http://www.astronomerswithoutborders.org/programs/lunar.html.

Sunday: 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 astronomy2009.nasa.gov/observe_apr.htm 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.

Monday: Tonight’s first quarter moon is six fists above due south at 8 p.m., midway between the bright stars Pollux above it and Procyon below.

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: Venus is a half a fist above the east horizon at 6 a.m.

Thursday: Are you thirsty? Crater the cup is two and half fists above the south-southeast horizon at 10 p.m. Hopefully you are not too thirsty because the cup is nearly tilted on its side. Its opening is pointing toward Saturn and Spica, the brightest objects in that portion of the sky.

Friday: Saturn is three fists above the southeast horizon at 10 p.m., one fist above Spica, the brightest star in the constellation Virgo.

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

Friday, April 1, 2011

The Ellensburg sky for the week of 4/2/11

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: The bright star Deneb is a half a fist above the north horizon at 11 p.m.

Monday: 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 four fists above the south horizon at 1 a.m. It is two fists above the southeast horizon at 9 p.m.
If you remember this column from 2/23/2008, 3/8/2009, and 3/21/2010, you know that Saturn was also in opposition on those dates. Thus, it is in opposition about two weeks later each year. Two weeks is about one twenty-fourth of a year. This implies that it takes Saturn about 24 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 quite well.

Tuesday: Give me a “W”. Cassiopeia, a W-shaped group of stars is two fists above the north horizon at 11 p.m.

Wednesday: Orion is getting lower and lower in the nighttime sky. Its second brightest star Betelgeuse is only one and a half fists above the west-southwest horizon at 11 p.m.

Thursday: This April, the hot topic in the tabloids is anyone in the Kardashian family. During April 2009, the International Year of Astronomy, the “Hot Topic” Astronomy was galaxies and the distant universe. When Galileo turned his telescope to the seemingly continuous band of light in the sky, he discovered it consisted of countless faint stars. This extended our celestial neighborhood from a few thousand stars to millions of stars. This neighborhood configuration lasted until the 1920’s when Edwin Hubble discovered that there are other galaxies with millions, or even billions, of stars just like our own galaxy. We may lose interest in celebrity break-ups but galaxies are always hot. At 11 p.m., you can see the thick band of the Milky Way galaxy starting at the northeast horizon, moving west through the bright star Deneb, through Cassiopeia, just above Betelgeuse and the Moon, under the feet of Gemini, and settling into the southwest horizon near Sirius, the brightest star in the nighttime sky. Follow this same track at this same time in a few nights when the Moon is not above the horizon to see the Milky Way even better.

Friday: Venus is a half a fist above the east horizon at 6 a.m.

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