Tuesday, March 29, 2016

The Ellensburg WA sky for the week of 4/2/16

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 two and a half fists held upright and at arm’s length above the east horizon at 10 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 give you a head start in celebrating International Dark Sky week, which starts tomorrow. 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. You won’t need to have dark skies to see Jupiter four fists above due southwest at 9 p.m.

Monday: It you didn’t run the Yakima River Canyon Marathon two days ago, satisfy that marathon craving by attending a virtual Messier Marathon. Charles Messier (pronounced messy a) was an 18th century French astronomer best known for his catalog of 110 nebulae and star clusters. Amateur astronomers love to find as many of these as they can in one night. During the online Messier Marathon, you’ll see the images broadcast on the Internet. The fun starts this morning at 11:00 a.m. Pacific Daylight Time (when astronomers on the nighttime side of Earth point their telescopes towards interesting celestial objects). For more information, go to http://goo.gl/e2cYkS.

Tuesday: The bright star Sirius is one and a half fists above the southwest horizon at 10 p.m.

Wednesday: Can’t sleep? Catch Saturn and Mars just above the southeast horizon at 1 a.m. Mars is the pale red dot a little more than a half a fist above the southeast horizon. Saturn is about half as bright and a half a fist to the lower left of Mars.

Thursday: The elusive Mercury is a half a fist above the west-northwest horizon at 8:30 p.m.

Friday: Two weeks ago, I asked you to watch the bright star Deneb to observe how its time at due north changes from night to night. It reached due north at 9:27 p.m. two Fridays ago. Tonight, it reaches due north at 8:32 p.m., 55 minutes earlier. As the Earth revolves around the Sun, it also rotates on its axis. (Wow Bruce, really? We learn so much from you!) Because it does both motions counterclockwise as viewed from above the Earth’s North Pole, any given spot on Earth faces the distant stars a little bit earlier each day than that spot faces the Sun. Based on the specific rotational and revolution speed, it amounts to three minutes and 56 seconds earlier each day. That’s 27.5 minutes earlier each week and… wait for it… wait for it… 55 minutes earlier every two weeks. Depending on where you live, those due north times may be off by a few minutes. But the two-week difference will be the same no matter where you live. (I apologize for my smart aleck statement earlier. You DO teach us a lot.)

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.

Sunday, March 20, 2016

The Ellensburg WA sky for the week of 3/26/16

Saturday: Has there ever been life on Mars? Astronomers don’t know. But the Mars Curiosity Rover has been digging up some strong evidence that Mars was hospitable to life in the past. At the end of 2012, the first drilling assignment for Curiosity found clay-like minerals that form in the presence of water. In December 2013, scientists announced the strongest evidence yet for an ancient fresh-water lake in Gale Crater. Planetary geologist John Grotzinger said that Earth microbes could have thrived in this lake if they were placed there. Last year, astronomers at the European Southern Observatory’s Very Large Telescope in Chile found evidence that Mars was once had an ocean that held more water than the Arctic Ocean and covered a greater percentage of Mars’ surface than the Atlantic Ocean does on Earth. In brief, they came to this conclusion after analyzing the chemical signature of light that passes through the Martian atmosphere. For more information about this ancient ocean and the method of discovery, go to http://goo.gl/bOqD4U. Mars is two fists held upright and at arm’s length above due south at 5 a.m. tomorrow morning. By the way, the name of the observatory in Chile really is Very Large Telescope. See for yourself at http://www.eso.org/paranal.

Sunday: The Space Shuttles have been retired. But NASA is still making plans about the future of space flight. Here is a small NASA poster summarizing the future of American Human spaceflight: http://goo.gl/D8KWj. It is interesting to compare the sizes of these real spaceships to the dozens of fictional spacecraft summarized on a poster found at http://goo.gl/F95aEL.

Monday: The moon passes by Mars and Saturn in the early morning sky for the next two mornings. This morning at 6 a.m., Mars is about a half a fist to the lower left of the Moon. Saturn is about a fist to the left of Mars. Tomorrow morning, the Saturn is almost directly below the Moon.

Tuesday: The bright star Arcturus is two and a half fists above due east at 10 p.m.

Wednesday: Jupiter is three fists above the east-southeast horizon at 8 p.m.

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 numerous arts initiatives and is looking for contributors, hopefully ones that are better than mine above. 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://astronomerswithoutborders.org/gam2016-programs/astroarts.html for more information about the AstroPoetry contest and a children’s AstroArt contest. The moon is expressing its love for Venus by moving upward in the early evening sky. At 8 p.m., Venus is about two finger widths to the right of the moon.

Friday: You need to get up early tomorrow to cheer on your favorite runners at the Yakima River Canyon Marathon starting at 8 a.m. on Canyon Road just south of Berry Road. So why not get a little viewing in? To symbolize the long trail of a marathon, follow the long trail of our own Milky Way Galaxy. It seems to rise up from the ground due south. It its highest, it is five fists above due east. It sinks back to the ground due north. The thickest part of the Milky Way is in the southern sky because that is the direction of the center of the galaxy.

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, March 16, 2016

The Ellensburg WA sky for the week of 3/19/16

 Saturday: 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 9:30 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”. 

Sunday: Geometry lesson in the skies: triangles.  Mars is about two and a half fists held upright and at arms length above the south-southwest horizon at 6 a.m. Mars is the right hand point of the triangle. Antares is the bright object about one fist to the lower left of Mars. Saturn is about a fist and a half to the left of Mars. Mars is about twice as bright as Saturn and Saturn is about twice as bright as Antares. 

Monday: Tonight is a great night to show yourself that the Moon changes its position throughout the night. When the Sun sets, Jupiter is to the upper left of the Moon low in the eastern sky. See how many fingers you can fit between the Moon and Jupiter. Try it again at midnight and at 6 a.m., just before the pair sets. You should notice the two getting farther apart in the sky. That's because the Moon is close enough to the Earth that its actual motion affects where we see it in the sky. The distant stars also move but they are so far away, it can take many centuries to detect their motion. 
Bonus activity: try to spot Jupiter just to the left of the Moon even before the Sun sets. 

Tuesday: The Milky Way is pretty easy to spot on the early spring sky. Just look up. Everything you see in the sky, including that bird that just startled you, is in the Milky Way. But, even the path of densely packed stars in the plane of our galaxy that look like a river of milk is easy to find. Look due south at 9 p.m. Follow the fuzzy path just to the left of the bright star Sirius two fists held upright and at arm’s length above the horizon, to the right of the bright star Procyon four and a half fists above the southwest horizon, through Capella five fists above the west horizon, through W-shaped Cassiopeia, and down to due north. 

Wednesday: Astronomers are often fascinated with large objects. Planets that could fit 1000 Earths (Jupiter). Stars that would fill up the entire inner Solar System (Betelgeuse). Galaxies with 400 billion stars (Milky Way). But what about the smallest objects? One of the smallest stars is Proxima Centauri, the closest known star other than our Sun. It is about 12% of the mass of the Sun. The smallest theoretically possible star would be about 7.5% of the mass of the Sun. Any smaller and it could not support fusion reactions. For more on small stars, go to http://goo.gl/EHBdOX. 

Thursday: Orion is getting lower and lower in the nighttime sky. Its second brightest star, Betelgeuse, is only two fists above the west-southwest horizon at 11 p.m. 

Friday: 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. At 10:22 tonight, it will be as close as it gets to the horizon, about two degrees above due north. Watch it reach this due north position about 4 minutes earlier each night. 

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

Monday, March 7, 2016

The Ellensburg WA sky for the week of 3/12/16

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 previous few 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 stays light for an additional hour.

Sunday: Tonight at 11 p.m., the V-shaped snout of Taurus the Bull points down at the Moon. An open star cluster called the Hyades Cluster dominates the snout and its area in the sky. Amateur astronomers noticed s pattern in the publically available Kepler data that looked like the sign of an exoplanet passing in front of, or transiting, one of the young, dwarf stars in the Hyades Clusters. Professional astronomers aimed their telescope at the star and tentatively confirmed the transit.

Monday: The group AC/DC sings that “Rock ‘n’ roll ain’t noise pollution, rock ‘n’ roll ain’t gonna die.” Unfortunately, because of excess and improper outdoor lighting in cities, even those as small as Ellensburg, our view of the night sky is gonna die. As plain old ordinary AC (Astronomy club) would sing: “Bad street lights are light pollution, our night sky IS gonna die.” Lights that are aimed upward illuminate the atmosphere and obscure dim objects. To watch an informative and entertaining video about the effects of light pollution, go to http://goo.gl/R1AoCz. To watch ACV/DC sing “Rock ‘n’ Roll Ain’t Noise Pollution, go to http://goo.gl/dZJ8my. To watch a dark sky object that is not affected by light pollution, look at Venus, just above the east-southeast horizon at 6:50 a. in the bright dawn sky.

Tuesday: “The crow rises in the southeast,” said spy number one. “I’m sorry. I don’t recognize that code,” replied spy number two. Spy one exclaimed, “That’s because it’s not a code, you idiot. I’m talking about the constellation Corvus the crow.” This very bad spy movie dialogue is to remind you that Corvus had a very bad life. According to one myth, Corvus brought the god Apollo the news that his girlfriend was seeing someone else. In a classic case of punishing the messenger, Apollo turned the formerly beautifully colored crow black. The box-shaped Corvus is one fist held upright and at arm’s length above the southeast horizon at 10 p.m.

Wednesday: 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.

Thursday: I hope you got your sweetie something red for Valentine’s Day two weeks ago. If not, I suggest a nice picture of the Red Valley on Mars. This January, the Mars Express probe took the first high-resolution stereo color image of Tinto Vallis, or Red Valley, the mouth of an ancient water flow on Mars. For more information and many photos of Tinto Vallis, go to http://goo.gl/ptJcr. Mars is three fists above due south at 5:30 a.m.

Friday: Did you the little triangle in the morning sky when you looked at Mars yesterday at 5:30 a.m.? Mars is the right hand point of the triangle. Antares is the bright object about one fist to the lower left of Mars. Saturn is about a fist and a half to the left of Mars. Mars is about twice as bright as Saturn and Saturn is about twice as bright as Antares.

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, March 2, 2016

The Ellensburg WA sky for the week of 3/5/16

Saturday: It’s getting dark. The last remnant of twilight has disappeared. Suddenly, you notice a large softly radiant pyramid of light in the western sky. The base of this ghostly triangle is along the west horizon and the peak stretches two or three fists above the horizon. It is not really a ghost. It is an effect called the zodiacal light. This light comes from sunlight reflecting off dust grains in our solar system. The effect is the most visible when the band of constellations called the zodiac makes a steep angle with the horizon. You need a clear dark sky with no haze or light pollution to see the zodiacal light. At its brightest, the zodiacal light rivals the light of the central Milky Way. Look for the ghostly patch after twilight for the next few weeks.

Sunday: Jupiter is opposition tomorrow night. That doesn’t mean that Jupiter is a teenager. Opposition means that Jupiter 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. Jupiter is five fists above due south at midnight. If you don’t want to stay up so late, you can see it two fists above the east-southeast horizon at 8 p.m.

Monday: Last week I wrote that astronomers estimated that asteroid 2013 TX68 will pass “close to” Earth. But I didn’t say when. That’s because they were not sure. The latest measurements have it pass somewhere between 15,000 miles and 3 million miles from Earth today or tomorrow. The uncertainty is so large because astronomers don’t know enough about its orbit. For more up to date information about 2013 TX68, go to http://goo.gl/5qUbhx.

Tuesday: Do you have a trip to Indonesia planned for today? If you do, make sure you observe the total solar eclipse. During a total solar eclipse, the Moon passes directly between the Earth and Sun, blocking the Sun’s light from hitting the Earth. Maximum eclipse happens today at 6 p.m. Ellensburg, Washington time and at about 9 a.m. March 9 in Jakarta, Indonesia. The San Francisco Exploratorium Museum has a live webcast of the eclipse at http://www.exploratorium.edu/eclipse/. The telescope feed goes from 4:00 to 7:15 p.m. and the actual webcast, with commentary, goes from 5:00 to 6:15 p.m. Pacific Standard Time today, March 8.

Wednesday: If the National Enquirer was around in Galileo’s day, it may have featured the headline: “Saturn has love handles; Opis leaves him for a much hotter starlet”. When Galileo first observed Saturn through a telescope, he reported objects that looked like bulges on either side of Saturn’s midsection. He was actually seeing Saturn’s rings through less than ideal optics. Saturn is two fists above the south horizon at 5:30 a.m. The star(let) Antares is about a fist to the lower right of Saturn. Antares’ rival, Mars, is about one and a half fists to the right of Mars, just on the other side of due south.

Thursday: Venus is just above the east-southeast horizon at 6 a.m.

Friday: It is often said that Earth is a water world because about 70% of the Earth’s surface is covered by water. What would it look like if all that water on the surface were gathered up into a ball? That “ball” would be about 700 km in diameter, less than half the diameter of the Moon. The Astronomy Picture of the day shows us right here http://goo.gl/4wXLM.

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.