Friday, June 29, 2012

The Ellensburg sky for the week of 6/30/12


Saturday: The constellation Cepheus the king is about four fists held upright and at arm’s length above the northeast horizon at 11 pm. Cassiopeia the queen is about one and a half below her husband Cepheus.  Cassiopeia looks like the letter “W” and Cepheus looks like a house on its side with the roof peak pointing towards the west. Cassiopeia and Cepheus revolve around the North Star every night like a happy couple going through life together.

Sunday: Wednesday night, while you are looking at an explosion of fireworks, the NASA spacecraft Kepler may be looking at an “explosion” of exoplanets. So far, Kepler has found 74 planets whose presence has been confirmed by other means and evidence of 2,321 planet candidates. Something is called a planet candidate when the light from a star being observed by Kepler dims in a systematic way. Astronomers still need to compare the pattern of dimming with the potential pattern of star wobble caused by being tugged on by one or more planets before they can say for certain that they have actually found planets orbiting these stars. But if even half of these stars show the characteristic wobble, it will more than double the number of planets known to orbit other stars, also known as exoplanets. And this is only the beginning. The Kepler spacecraft is monitoring the brightness of over 156,000 stars in the constellations Cygnus the swan and Lyra the lyre. This region is midway between the bright stars Deneb and Vega. It is about the size of your hand held at arm’s length and is about six fists held upright and at arm’s length above due east at 11 p.m. For more information about the Kepler mission, go to http://kepler.nasa.gov/.

Monday: Last week, I wrote about Mizar. This week, I need to warn you not to confuse Mizar with its rhyming brother Izar in the constellation Bootes. Izar is also a binary star with about the same apparent brightness. And both were featured in different episodes of Star Trek. Izar was featured in the Star Trek episode “Whom Gods Destroy” from the original series. It is the base of Fleet Captain Garth, a former big shot in the federation and one of Kirk’s heroes before he went insane. Garth kidnaps Kirk and Spock before eventually being out smarted. Mizar doesn’t play as big a role in its episode. It is the star of the home world of one of the alien species in The Next Generation episode “Allegiance”. Izar is one fist above the bright star Arcturus and seven fists above the south horizon at 10 p.m. Mizar is seven fists above the northwest horizon at this time.

Tuesday: July is typically the month when the antlers of a young buck push out of its head so some Native American groups call this month’s full moon the Full Buck Moon. Tonight, the Full Buck Moon is in the constellation Sagittarius the archer.

Wednesday: Hot enough for you? Don’t blame the Earth-Sun distance. Surprisingly, the overall temperature of the Earth is slightly higher in July, when the Earth is farthest from the Sun, than in January, when it is closest. That’s because in July, the Northern Hemisphere is tilted towards the Sun. (This is the real cause of the seasons.) The Northern Hemisphere has more land than the Southern Hemisphere. Thus, in July, the large amount of Northern Hemisphere land heats up the entire Earth about two degrees Celsius warmer than in January. In January, the watery Southern Hemisphere is tilted toward the Sun. But, water does not heat up as fast as land so the Earth is a few degrees cooler. The distance between the Earth and Sun is its greatest today, 152.1 million kilometers. This is called aphelion from the Greek prefix “apo” meaning “apart” and Helios, the Greek god of the Sun.

Thursday: Saturn and Mars are both in the constellation Virgo for the next few weeks. At 11 p.m., Saturn is two fists above the southwest horizon and a half a fist above the bright bluish star Spica. The reddish planet Mars is a little more than a fist above the west-southwest horizon.

Friday: The bright star Antares at the heart of Scorpius the scorpion is a fist and a half above the south horizon at 11 p.m.

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

Tuesday, June 19, 2012

The Ellensburg sky for the week of 6/23/12


Saturday: Don’t wait until the 4th of July to go to those wimpy firecracker shows. Find the hypergiant star Rho Cassiopeiae. Astronomers think that Rho Cassiopeiae will likely go supernova (explode) in the near future. Of course, for stars, near future might mean today. It might mean 20,000 years from now. Rho Cassiopeiae is in the constellation Cassiopeia the queen. At 11:00 tonight, Cassiopeia looks like the letter “W” about three fists held upright and at arm’s length above the northeast horizon. Rho Cassiopeiae is about a finger’s width to the right of the rightmost star in the “W”. Once you find it you’ll be thinking, “Big deal, I can hardly see it.” Although it is barely visible to the naked eye, it is actually very bright. It is the 20th most luminous star in the sky, a whopping 550,000 times more luminous than the Sun.

Sunday: Go outside and find the bright star Regulus, about a fist to the right of the Moon at 11 p.m.

Monday: Mars is less than a fist above Moon at 11 p.m. Since you also observed that the Moon was near Regulus last night…. You did observe the Moon last night, didn’t you? I asked you to. A civilized society thrives because its people honor the reasonable requests made by others. If you just say “yes” and ‘no” whenever you feel like it, human interactions grind to a halt. Okay, enough with the guilt trip. Back to astronomy. Since you also observed that the Moon was near Regulus last night, you can approximate how far it appeared to move. It moved a little more than one fist. Since one fist held at arm’s length subtends an angle of 10 degrees. The Moon moved about 13 degrees through the sky. In 28 days, the Moon will have moved about 360 degrees (13 degrees/day X 28 days). 360 degrees brings it back to where it started. Thus, making one simple measurement, how far the Moon moves through the sky in one day, you can determine the length of the lunar cycle.

Tuesday: “If you don’t maneuver more carefully, we are going to crash.” How often do you hear that while driving? Well, the Milky Way Galaxy is going to hear that a lot over the next four billion years. After carefully analyzing the motion of the Andromeda Galaxy, astronomers have determined that the Andromeda and the Milky Way are on a collision course. To locate the Andromeda Galaxy before it ends up in your backyard, first find the Great Square of Pegasus. At midnight, the left hand corner of the square is about one fist above the east-northeast horizon. Less than two fists to the left and down a little bit is another star the same brightness as the star at the corner of the square. From that star, hop about a half a fist up to a star that is about one fourth as bright. Less than another half fist in the same direction is a fuzzy oval patch of light known as the Andromeda Galaxy. The galaxy is impressive to see in binoculars. It consists of about 400 billion stars and is 2.2 million light years away. Go to http://hubblesite.org/newscenter/archive/releases/2012/20/ to read more about the upcoming collision.

Wednesday: The bright star Spica is about a half a fist to the upper left of the Moon at 10 p.m. Saturn is about a half a fist above Spica.

Thursday: Jupiter is one fist above the east-northeast horizon at 4:30 a.m. The much brighter Venus is a half a fist below Jupiter.

Friday: Mizar is a well-known binary star in the constellation Ursa Major. You can find it at the bend in the Big Dipper handle, nearly straight overhead at 10 p.m. tonight. Its name is Arabic for waistband. Mizar has an optical double called Alcor which is less than a pinky width away and can easily be seen with the naked eye. Optical doubles are stars that are close together in the sky but do not orbit a common center of mass as true binary stars. Not wanting to deceive sky gazers who call Mizar a binary star, two stars that DO orbit a common center of mass, Mizar actually is a binary. It was the first binary star system discovered by telescope. Mizar A and Mizar B are about 400 astronomical units apart from each other and about 80 light years from Earth. 400 astronomical units is about 10 times the distance between the Sun and Pluto.

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

Thursday, June 14, 2012

The Ellensburg sky for the week of 6/16/12


Saturday: “Mom, I can’t sleep. It is too light out!” A poor excuse you say? Good astronomy skills, I say. The latest sunset of the year happens over the next two weeks. Surprisingly, the earliest sunrise and the latest sunset do not both happen on the longest day of the year, the day of the summer solstice. The earliest sunrise occurs just before the longest day and the latest sunset occurs just after the longest day. (The earliest sunrise happened last week.) This phenomenon relates to the angle of the Sun’s path near rising and setting. In Ellensburg, that angle is about 66 degrees near the first day of summer. Because of the Earth’s orbit, which causes the Sun’s apparent motion, the angles are not symmetric. The asymmetry in orbital angles leads to the asymmetry in rise and set times. By the way, the “can’t sleep because it is too light out” line may just be an excuse because the sunset times change by only a few seconds each day this time of year. The sun sets between 9:01 and 9:02 p.m. between June 21 and July 3 2012.

Sunday: Do you have a dad that is so great that you wish you could write his name in galaxies? Now you can. UK astronomer Steven Bamford has developed a computer program that finds images of galaxies that resemble different letters. Just enter the words here http://goo.gl/dTkPE and the program spells it out in galaxies. Here’s a word I learned from the Ellensburg High School class of 2012 http://mygalaxies.co.uk/ssmcyi/. And here’s the new Daily Record title page http://mygalaxies.co.uk/jh2m7m/.

Monday: Summer is nearly here. How do I know? Because my kids are home from school. Also, because the Summer Triangle is fairly high in the eastern sky at 10 p.m. Vega, the third brightest star visible from Ellensburg, is about five fists held upright and at arm’s length above the east horizon. Deneb, at the tail of Cygnus the swan is about three and a half fists above the northeast horizon. The third star in the triangle, Altair, in Aquila the eagle is two fists above the east horizon.
If you want to put somebody off, tell her or him to wait until Deneb sets. At Ellensburg’s latitude of 47 degrees, Deneb is a circumpolar star meaning it never goes below the horizon.

Tuesday: 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. This is why some people call this phase the “dark moon” and reserve the name “new moon” for the first visible waxing crescent after the Moon moves out from directly between the Earth and Sun.

Wednesday: Today is the first day of summer, the day that the Sun reaches its highest declination (the official name for sky latitude) of 23.5 degrees above the celestial equator. The celestial equator is the line that divides the northern sky from the southern sky. In Ellensburg, the Sun is about seven fists held upright and at arm’s length above the south horizon at 1:00 p.m. (noon standard time). Contrary to popular belief, the Sun is never straight overhead in Ellensburg or anywhere else in the 48 contiguous states. The northernmost portion of the world where the Sun can be directly overhead is 23.5 degrees north latitude. In ancient times, the Sun was in the constellation Cancer the crab on the first day of summer. Hence, 23.5 degrees north latitude has the nickname "Tropic of Cancer". Because the Earth wobbles like a spinning top, the Sun's apparent path through the sky changes slightly over time. Now, the Sun is in the constellation Taurus the bull on the first day of summer. However, citing the high cost of revising all of the science books, geographers are not changing the name of 23.5 degrees north latitude to "Tropic of Taurus". The first day of summer is often called the summer solstice. However, astronomers refer to the summer solstice as the point in the sky in which the Sun is at its highest point above the celestial equator. Thus, summer starts when the Sun is at the summer solstice point. This year, that happens at 4:07 p.m.

Thursday: Saturn is two and a half fists above the southwest horizon and Mars is two fists above the west-southwest horizon at 11 p.m.

Friday: The bright orangish star Arcturus is five and a half fists above the southwest horizon at 11 p.m. Don’t confuse it with Saturn, a similarly colored object much lower in the sky

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

Thursday, June 7, 2012

The Ellensburg sky for the week of 6/9/12


Have you bought your favorite CWU graduate a graduation gift yet? Why not get her or him a star? I don’t mean from one of those organizations that offers to “register the name of YOUR star with the U.S. Patent Office”. No company owns the right to name stars after people. Besides, the stars those companies “name” are so dim you can’t find them. In this column, I’ll pick a constellation and representative star for each of the four colleges at CWU. Then, I’ll briefly tell the story of the constellation and relate that story to the aspect of public service CWU graduates from that college are uniquely qualified to engage in based on my version of sky interpretation. A couple can have “their” song so your favorite CWU graduate can have her or his star.

Saturday: Just as gyms and stadiums have been filled with smart people for many evenings for the past few weeks, the sky is filled with planets. Since Mercury sets early, start there. Mercury is a half a fist held upright and at arm’s length above the northwest horizon at 9:30 p.m. At 10 p.m. when it is a little darker, find Mars three and a half fists above the northwest horizon and Saturn three and a half fists above the south-southwest horizon. By 4:30 a.m., Jupiter is just peeking up above the east-northeast horizon.

Sunday: College of Arts and Humanities: You are the people who interpret the world in unique ways. Then, you share those ways with others. According to Greek mythology, Orpheus charmed everyone he met when he played the lyre or harp. After his wife died tragically, he journeyed to the underworld to charm its inhabitants in an effort to win his wife back to the living world. Your service reminder: use your talent to bring joy to others. The constellation Lyra and its bright star Vega should remind you of the power of the arts. Vega is five fists held upright and at arm’s length above the southwest horizon at 11 p.m.

Monday: College of Business. You are the future movers and shakers. The future CEOs. The future big donors to Central. Auriga represented a king of Athens who happened to be mobility impaired. Instead of sitting around waiting for others to transport him, he took the initiative to invent the four-wheeled chariot. He solved a problem for a special need. Your service reminder: address the problems of those in the most need. To remind you of that, look to the constellation Auriga. Its bright star Capella is about one fist above the north horizon at 11 p.m.

Tuesday: Last Tuesday was the last Transit of Venus for the next 105 years. Where were you? If you were one of 156 intrepid people who braved the wind and five dogs that tried to eat our chips, you were on the corner of 18th Avenue and Walnut Street safely looking at the Venus Transit. There are a few pictures on the CWU Astronomy Club Facebook page: http://www.facebook.com/CWUAC. An astrophotographer in Australia captured the Hubble Space telescope transiting the Sun in one second during the Venus Transit. Go to http://goo.gl/TIdMS for more information.

Wednesday: College of Education and Professional Studies. You are the teachers. The craftspeople. The facilitators of learning in a diverse world. Bootes, the herdsman, was such a person. Bootes’ job was to guide the northern constellations to the feeding place and the watering hole. He and his dogs were especially in charge of Ursa Major and Ursa Minor, the greater and lesser bears. Your service reminder: guide others to a better place in life. Look to the constellation Bootes and its bright star Arcturus to remind you of this. Arcturus is six fists above the southwest horizon at 11 p.m.

Thursday: College of the Sciences. You are the people who will systematically study how the world works. Agriculture is an important scientific application. Each year, farmers must use the findings of science to be successful. Who better to represent the College of the Sciences than Virgo, the goddess of the harvest? Virgo looms large in the sky holding an ear of wheat in her hand. Your service reminder: study the practical aspects of the scientific world. The ear of wheat, and your service reminder, is represented by the bright star Spica. Spica is two and a half fists above the southwest horizon at 11 p.m.

Friday: Altair, in the constellation Aquila the eagle, is two fists above the east horizon at 11 p.m.

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