Thursday, March 28, 2013

The Ellensburg sky for the week of 3/30/13

Saturday: Jupiter is three and a half fists held upright and at arm’s length above the west horizon at 9 p.m.

Sunday: Next Saturday, about 500 people will be in town to run a marathon. If you have not trained, you’re not ready. Instead, 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 at 11 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

Monday: 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 is too close to the Sun in the evening sky to be visible. So you’ll have to be content reading about it at

Tuesday: 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.

Wednesday: Typically there are no cheers when spacecraft crash. Except for the Death Star. But when the twin lunar satellites from the Gravity Recovery And Interior Laboratory (GRAIL) ended their mission on December 17, 2012, astronomers hailed it as a job well done. The twin spacecraft spent a year orbiting the moon and mapping subtle differences in its gravitational pull to help astronomers better determine the structure and history of the moon. The best summary of the GRAIL data is this Astronomy Picture of the day, which would fit right in on a t-shirt at a Grateful Dead concert ( If you didn’t stay up late “Driving that train, high on… life”, look for the moon in the southern sky this morning.

Thursday: The bright star Arcturus is three fists above the east horizon at 10 p.m.

Friday: Saturn is about one fist above the east-southeast horizon at 10:30 p.m. You shouldn’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.

Wednesday, March 20, 2013

The Ellensburg sky for the week of 3/23/13

The night sky above.
Shows our past and our future.
We’re made of star stuff.

Saturday: There are two comets visible in the night sky of you are blessed with clear skies, an open west-northwest horizon and lots of frequent flier miles to use. The easiest one to find is Comet PANSTARRS, names for the acronym of the project that found it. While it reached peak brightness two weeks ago, you can find it 30 minutes after sunset about a fist held upright and at arm’s length above the west-northwest horizon. For more information on finding Comet PANSTARRS, go to Comet Lemmon is currently visible only in the southern Hemisphere. Over the next few weeks, it will move into the northern hemisphere sky but get dimmer, remaining an object to view through binoculars. But just because you can’t see Comet Lemmon doesn’t mean you can’t learn about it. See for information and a finder chart for Comet Lemmon.

Sunday: Jupiter is five fists above the west-southwest horizon at 8 p.m.

Monday: Saturn is about a half a fist above the east-southeast horizon at 11 p.m. By 6 a.m. tomorrow, it has moved all the way across the sky to be two fists above the southwest horizon.

Tuesday: Tonight’s full moon is in the constellation Leo the lion. While we may refer to the moon tonight by the boring title, “a full moon in March”, Native Americans in the eastern United States called this moon the Full Worm Moon. By March, the temperature has increased enough so the ground starts to thaw and earthworms make their first appearance. Earthworms attract birds. Northern tribes thought of the bird connection when they referred to the March full moon as the Full Crow Moon. Tribes in parts of the country with maple trees call this full moon the Full Sap Moon. For more full moon names, go to

Wednesday: Watch the bright star Spica as it chases the moon across the sky tonight. The overall motion of the two objects is due to the rotation of the Earth. But since the moon orbits the earth and is close to the earth, its actual motion can be detected. It is one of the few objects that we can see move in the sky over a matter of hours. It goes from being a half a fist ahead of Spica at 10 pm tonight to about a thumb width ahead at 6 a.m. tomorrow.

Thursday: 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 10:13 p.m. two Thursdays ago, blah explain this

Friday: 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, 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 for more poetry.

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

Tuesday, March 12, 2013

The Ellensburg sky for the week of 3/16/13

Saturday: Has there ever been life on Mars? Astronomers don’t know. But the Mars Curiosity Rover just drilled up some strong evidence that Mars was hospitable to life in the past. The first drilling assignment for Curiosity found clay-like minerals that form in the presence of water. Moreover, the water probably had a nearly neutral pH. According to project scientist John Grotzinger, “if this water was around and you had been on the planet, you would have been able to drink it.” For more information, go to

Sunday: 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.
While you are thinking about this, go outside at 8 p.m. and find the moon in the southwest sky. Jupiter is about two finger widths to the upper right of the moon and the bright star Aldebaran is about a half a fist to the lower left of the moon. Watch over the next four hours as the moon slowly moves above the line between Jupiter and Aldebaran. The overall motion of the three objects toward the western horizon is due to the rotation of the Earth. But since the moon orbits the earth, its actual motion can be detected. It is one of the few objects that we can see move in the sky over a matter of hours.

Monday: Saturn is one fist above the southeast horizon at midnight. By 6 a.m., it is all the way over into the southwestern sky, nearly two and a half fists above the horizon.

Tuesday: Arcturus is three fists above the east horizon at 11 p.m.

Wednesday: 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 3:02 a.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”.

Thursday: So far this week, I have written about Saturn, 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 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.

Friday: The bright star Vega is about one fist above due northeast at midnight.

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

Thursday, March 7, 2013

The Ellensburg sky for the week of 3/9/13

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.

Sunday: Comet watchers haven’t had much to cheer about recently. But this year is looking up (pun intended) because astronomers think there will be two comets visible to the naked eye. The first one is called Comet C/2011 L4 after the year and date of its discovery or Comet PanSTARRS, after the Panoramic Survey Telescope and Rapid Response System that discovered it. It reaches maximum brightness today but it will be too low in the sky for most observers in the northern United States. It will be just above the west horizon, a little north of due west, right after sunset. You’ll need binoculars to pick it out. For more information, go to

Monday: Mars is a half fist above the west horizon at 7:15 p.m., just after sunset. 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 2011 to collect material from Phobos crashed to Earth after malfunctioning. For more information about this new model of Phobos’ formation, go to

Tuesday: If you had trouble finding Comet PanSTARRS earlier in the week, you’ll have a great marker tonight. The comet will be less than half a fist to the left of the crescent moon just after sunset. Probably the best time to look will be about 7:30 p.m. The Sun will have set 30 minutes earlier but the moon and comet will still be a fist above the west horizon. The comet’s tail will still be pointing away from the sun, which is right under due west. Throughout the rest of the month, the comet will be getting higher in the sky but dimmer. Currently, the comet is about magnitude 2, similar to the brightness of the Big Dipper stars.

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

Thursday: 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 10:13 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.

Friday: Saturn is about a fist above the east-southeast horizon at midnight. If you are more of a morning person, you’ll see Saturn two and a half fists above the southwest horizon at 6 a.m.

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