Sunday, April 15, 2012

The Ellensburg Sky for the week of 4/21/12

Saturday: 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 new so expect to see up to 20 bright meteors per hour. 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.

Sunday: You know Metis and Thebe and Adrastea and Amalthea. Io and Ganymede and Callisto and Europa. But do you recall? There are 65 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 65 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 4, 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.

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

Tuesday: Venus is about a half a fist to the upper right of the Moon at 9 p.m. Both objects are low in the western sky.

Wednesday: “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://goo.gl/BZqbL to read more about solar system water.

Thursday: At 10 p.m., Mars is about five and a half fists above the south horizon and Saturn is about two and a half fists above the southeast horizon. Saturn is slightly brighter and orange compared to the bluish star Spica to its lower right.

Friday: 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.

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

Thursday, April 12, 2012

The Ellensburg Sky for the week of 4/14/12

Saturday: This week is International Dark Sky week, a time during which people around the world are encouraged to turn off any unnecessary outdoor lights in order to temporarily reduce light pollution. Light pollution is the adverse effect of unwanted light including sky glow, glare, and light clutter. If you think that there is not much sky glow, or wasted light, in the world, look at the nighttime image of the Earth at http://www.cc.gatech.edu/~pesti/night/. While turning off a few unnecessary outdoor lights for one week will not solve the problem of light pollution, International Dark Sky Week will raise awareness of the issue. You can do your own dark sky test. At 10 p.m., look in the sky starting at the southwest horizon, moving to about halfway up in the western sky and back down to due north. If you can see the faint glow of the Milky Way Galaxy, you are observing from a dark site. 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 for the next two weeks.

Sunday: 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 and a half fists above the south horizon at 1 a.m. It is one fist above the east-southeast horizon at 9 p.m.
If you remember this column from 2/23/2008, 3/8/2009, 3/21/2010, and 4/4/11, 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.

Monday: 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.

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.

Wednesday: Mercury will be as far away from the Sun in the sky as it will get this orbital cycle. This "farthest away" point is known as the planet's greatest elongation. Since Mercury is in morning sky, it is west of the Sun and this occurrence is called the greatest western elongation. This morning will be the best mornings to observe Mercury for the next few weeks. Mercury is about a half a fist above the east horizon at 6 a.m., between the horizon and the Moon Over the next few weeks, Mercury will move toward the Sun in the sky. By early June, it will be visible in the evening sky.

Thursday: Jupiter is fading in the evening sky. It is less than half a fist above the west-northwest horizon at 9 p.m.

Friday: At 10 p.m., Venus, the brightest point of light in the night sky, is two fists above the west-northwest horizon and Mars is five and a half fists above the south horizon.

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

Wednesday, April 4, 2012

The Ellensburg Sky for the week of 4/7/12

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 middle of the right-hand column. One of the feature events for this week is a video entitled “Space Trip” featuring new works by the Austrian artist Thomas Riess. His work is abstract yet there is a certain familiarity to it. Go to http://goo.gl/EffgU either today or tomorrow to read more about his work and for a link to the video.

Sunday: The Big Dipper is nearly straight overhead at 11 p.m., spilling its contents all over the north horizon.

Monday: On March 31, over 600 people ran a real road marathon from Ellensburg to Selah. Today at 1 p.m. Pacific Daylight time there will be a virtual Messier Marathon. In a road marathon, you run far and look at the backs of the people ahead of you. In a Messier Marathon, you look at objects that are far away. The Messier Object Catalogue consists of 110 fuzzy objects that were difficult to distinguish from comets in late 18th century telescopes. These can be a challenge to find on your own. That’s why you should participate in the virtual marathon at http://virtualtelescope.bellatrixobservatory.org/mm2012.html. Astronomers on the nighttime side of the Earth will point their telescope at the Messier objects and stream the images live in the internet.

Tuesday: Antares is a half a fist to the lower right of the Moon at 5 a.m.

Wednesday: 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.

Thursday: Mars is five and a half fists above the south horizon and Saturn is two fists above the southeast horizon at 10 p.m.

Friday: If Friday the 13th is supposed to be unlucky, then this is your unlucky year. There are three Fridays that fall on the 13th this year! And they occur 13 weeks apart! And the government is charging an extra $13 tax those Fridays! Okay, I made up that last one. But I’m not making up that Aldebaran is the 13th brightest star in the nighttime sky. At 9 p.m. tonight, it is about a fist to the lower left of Venus and two fists above due west. At this time, Jupiter is about a half a fist above the west-northwest horizon.

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

Tuesday, March 27, 2012

The Ellensburg Sky for the week of 3/31/12

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: After a long journey through space, there is nothing will quench your thirst better than a few drops of refreshing Mars water. Wait! Is this an April Fool’s Day joke? No. In 2010, after analyzing photos taken by the Mars Phoenix Lander, a group of astronomers discovered what they interpreted as drops of very salty liquid water on one of the Lander’s legs. But we are not going to travel 18 months to Mars just to lick a few drops of water off a metal leg. We want waterfront property if we are going all that way. The high-resolution camera aboard the Mars Reconnaissance Orbiter has taken images of dark rivulets form, grow, and fade in the Martian southern hemisphere. Even though Mars is very cold, this liquid could contain enough salt to lower its freezing point by more than 100 degrees Fahrenheit. Mars and its refreshing water is five fists above the southeast horizon at 9 p.m. For more information about liquid water on Mars, go to http://goo.gl/HEGxe.

Monday: The Moon must be thirsty tonight because it moves close to Mars in the night sky. At 9 p.m., the Mars is less than one fist to the left of the Moon. Regulus, the brightest star in the constellation Leo, is right in between the two.

Tuesday: Jupiter is two fists and Venus is nearly four fists above the west horizon at 8 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: The bright star Vega is a little more than one fist above the northeast horizon at 11 p.m.

Friday: Tonight’s full Moon gets an escort through the night sky: the planet Saturn and the star Spica. Why? Because it is perfect. In fact, they’ll spend the night serenading the Moon with the song by the artist P!nk: “Pretty, pretty please, don’t you ever, ever feel, like your less than, less than perfect”. (The Moon would not want to hear the version of the song with the “F” word.) Some Native American tribes call the April Full Moon the Full pink Moon, or maybe the Full P!nk Moon, because its arrival coincides with the blooming of wild ground phlox, a pink wild flower. At 9 p.m., Saturn is a half a fist and Spica is a thumb-width to the left of the Moon.

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

Friday, March 23, 2012

The Ellensburg Sky for the week of 3/24/12

Saturday: Just as clouds can ruin an observing opportunity on Earth, they can get in the way on Mars, as well. Astronomers wanted to measure seasonal changes in the icy sand dunes by taking new photos with the Mars Reconnaissance Orbiter. But clouds obscured the view http://goo.gl/Ec9ZR. Hopefully clouds will not keep you from seeing Mars four and a half fists held upright and at arm’s length above the southeast horizon at 9 p.m. If they do, get up early and catch Mars one fist above the west horizon at 5 a.m.

Sunday: Someone told the Moon that he is shy, that he needs to get out and meet people. So, tonight he meets Jupiter, the king of the planets, named after the king of the Roman gods. Jupiter is a half a fist to the lower left of the Moon at 8 p.m.

Monday: Wow. Just one night of practicing his new social skills and the Moon is ready to date. But whom does he choose? Does the Moon want to hang out with the Goddess of Love or seven sisters? Why decide? Tonight he has both… or all eight… or all 1000. Venus, as we learned from Frankie Avalon, is the Goddess of Love and, as we learned from ancient astronomers, the second planet from the Sun. The Pleiades is an open star cluster consisting of seven easily visible stars, hence the name Seven Sisters. Astronomers have discovered more than 1000 stars overall in the Pleiades. At 9 p.m., the Moon, Venus, and the Pleiades make an isosceles triangle with the Moon at the apex angle, Venus a half a fist to the lower right of the Moon and the Pleiades a half a fist above the Moon.

Tuesday: At the beginning of the week, the Moon was a follower. Now it is a leader and Aldebaran is the follower. Aldebaran, is the brightest star in the constellation Taurus the bull. Its name is Arabic for “follower” because if follows the Pleiades in the night sky. Tonight it follows a half a fist to the lower left of the Moon at 9 p.m. While Aldebaran appears to be part of a star cluster, it is actually between Earth and the Hyades open star cluster.

Wednesday: Let’s take a break from the Moon and look at a different part of the sky. For the past few weeks, Saturn and Spica have been moving through the night sky together. At 11 p.m., they are two fists above the southeast horizon. Saturn is slightly brighter and positioned to the left of Spica. Even though planets such as Saturn move with respect to the background stars, Saturn is far from the earth and will remain close to this position with respect to Spica for a few months.

Thursday: April is Global Astronomy Month (GAM). While many astronomy experiences come from looking up, you can also experience astronomy looking down… at pen and paper. GAM has launched an Astropoetry blog and is looking for contributors. Even if you’ve never written a poem before, this is your opportunity to express your love for astronomy in a unique way and possibly share it with others. Go to http://www.astronomerswithoutborders.org/projects/astropoetry-blog.html for more information.

Friday: Tonight’s first quarter moon is in the constellation Gemini. Don’t stay up too late watching it. You need to get up early to cheer on your favorite runners at the Yakima River Canyon Marathon tomorrow at 8 a.m. on Canyon Road just south of Berry Road.

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

Tuesday, March 13, 2012

The Ellensburg Sky for the week of 3/17/12

Saturday: Mars is four and a half fists held upright and at arm’s length above the southeast horizon at 10 p.m. Its two small moons, Phobos and Deimos, are not visible in typical backyard telescopes. But they are an interesting study. The prevailing view among most astronomers is that they are captured asteroids. That makes sense given Mars’ proximity to the asteroid belt. But resent findings by European astronomers indicate that Phobos is very porous and made of material similar to the surface of Mars. This implies that Phobos may consist of chunks of Martian debris that was blasted off by numerous impacts and gravitationally bound together. Unfortunately, the Russian Phobos-Grunt probe launched late last year to collect material from Phobos crashed on Earth after malfunctioning. For more information about this new model of Phobos’ formation, go to http://goo.gl/g4cdp.

Sunday: Apparently, Venus and Jupiter had a falling out. Venus is moving away from Jupiter in the night sky. They are about three fists above the west horizon at 8 p.m. The much brighter Venus is about a half a fist above Jupiter. Watch them move farther apart as the week goes by, like a Kardashian woman and her NBA star.

Monday: Look up in the sky. It’s a plane. It’s a bird. No, it’s the vernal equinox. The vernal equinox!? Spring starts at 10:13 p.m. Pacific Daylight Time. The first day of spring is often called the vernal equinox. This label for the day is misleading. The vernal equinox is actually the point in the sky where the Sun’s apparent path with respect to the background stars (called the ecliptic) crosses the line that divides the stars into north and south (called the celestial equator). This point is in the constellation Pisces the fishes. At the vernal equinox, the Sun is moving from the southern region of background stars to the northern region. Since the Sun crosses the vernal equinox at night, tomorrow will actually be the first full day of spring.
Because the Earth slowly wobbles like a spinning top, the vernal equinox is slowly moving into the constellation Aquarius. By the year 2597, the vernal equinox will reach the constellation Aquarius and the “Age of Aquarius” will begin. Until then, we’ll be in “the age of Pisces”.

Tuesday: Still worried about 2012? Don’t be. Watch http://www.universetoday.com/94080/still-concerned-about-2012/.

Wednesday: Sirius, the brightest star in the nighttime sky, is two and a half fists above due south at 8 p.m.

Thursday: 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 20, the New Moon will be covering most of the Sun leading to an annular solar eclipse. What is an annular solar eclipse? More on that as the eclipse time draws nearer.

Friday: So far this week, I have written about Venus, Mars, and Jupiter. Do you even care about these planets or does another planet really catch your fancy? If you’d like to know what most people’s favorite planet is, go to http://www.pbs.org/wgbh/nova/pluto/favorite.html and click on “Launch Interactive”. The public TV special called “The Pluto Files” has set up a website in which astronomers give a 30-second pitch for why a certain planet is their favorite. After listening to the pitch, you may vote for your favorite planet. Of course, you may also do what most people do for political elections: vote for the candidate with the best name or the one with the most interesting campaign slogan. So whether you carefully consider each planet or simply “Swoon for Neptune”, “Jump for Jupiter”, or “Pick Uranus”, go to “The Pluto Files” and vote. Saturn will be holding a campaign rally tonight at 11 p.m., nearly two fists above the southeast horizon.

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

Wednesday, March 7, 2012

The Ellensburg Sky for the week of 3/10/12

Saturday: Don't forget to set you clocks ahead one hour tonight for the annual ritual called daylight savings. Daylight savings originated in the United States during World War I to save energy for the war effort. But a recent study by two economists shows that switching to daylight savings time may actually lead to higher utility bills. When the economists compared the last three years of energy bills in the section of Indiana that just started observing daylight savings, they discovered that switching to daylight savings cost Indiana utility customers $8.6 million in electricity. In an even more important consequence of daylight savings, Stanley Coren of the University of British Columbia discovered a 7% jump in traffic accidents on the Monday after we "spring ahead". Blame it on the lost hour of sleep. And, sky watchers will lose even more sleep because the sky does not get dark for an additional hour.
You won’t need to be very wide-awake to find a bright planet conjunction every night this week. Venus passes by Jupiter in the early evening sky throughout the week. Tonight Jupiter is less than a half a fist to the upper left of the very bright Venus. They are three fists held upright and at arm’s length above the west horizon at 7 p.m. Because of daylight savings, they’ll be at this altitude (number of degrees above the horizon) at 8 p.m. the rest of the week. If anyone you know needs evidence that objects in the night sky actually move with respect to each other, the motion of Venus compared to Jupiter is a highly visible example.
Before you go inside tonight, be sure to look for Mercury, a half a fist above the west horizon. By the end of the week, it will be too close to the Sun to be easily visible.

Sunday: Mercury is the naked eye planet we know the least about. You may not have even knowingly seen it until reading yesterday’s exciting section of “What’s up in the sky”. That global lack of knowledge is rapidly going away because NASA’s Messenger probe has been orbiting Mercury for one year as of this week. It is the first visitor since 1974 to the planet that one Messenger scientist called the most under-appreciated planet. The number one question scientists hope to answer is why Mercury has such a large iron core compared to its size. The number one question you may be asking is “Why is Mercury noticeably closer to the horizon since yesterday?”. Since Mercury is so close to the Sun, it moves very fast in its orbit so it changes positions in the sky much faster than anything other than the Moon.

Monday: Mars is three and a half fists above the east-southeast horizon at 9 p.m.

Tuesday: Antares is one and a half fists above due south and about a half a fist to the lower left of the Moon at 6 a.m. this morning.

Wednesday: This morning’s almost last quarter Moon is in the constellation Ophiuchus, the serpent bearer.

Thursday: Saturn is one fist above the east-southeast horizon at 11 p.m.

Friday: Ask someone which day in March has the same duration day and night. Go ahead, ask someone. Why are you still reading this? I can wait. If that person said the first day of spring, they are wrong. Today, three days before the first day of spring, is the date in which day and night are closest in duration. There are two main reasons for this. First, the atmosphere acts like a lens, bending light from the Sun above the horizon when the Sun is actually below the horizon. This makes the Sun appear to rise before it actually rises and appear to set after is actually sets. Second, spring starts when the center of the Sun passes through the point called the vernal equinox. But, the Sun is not a point. The upper edge of the Sun rises about a minute before the center of the Sun and the lower edge sets a minute after the center of the Sun. Thus, even if we didn’t have an atmosphere that bends the sunlight, daytime on the first day of spring would still be longer than 12 hours.

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