The Ellensburg sky for the week of 9/28/13

Saturday: Mnemonics are helpful for remembering astronomy facts. (Similarly, “Johnny Mnemonic”, the 1995 cyberpunk film, was helpful in getting Keanu Reeves’ career going.) After all, school children all around the country are learning the order of the planets by remembering, “My very excellent mother just served us nine….” Oops, I guess that one needs updating. Well, here’s one that will not need updating for nearly 100,000 years: the order of the stars in the Big Dipper. Because the nighttime stars are so far away from us, their actual motion through the sky, called their “proper motion” is not noticeable over even thousands of years. That is why the constellations have remained the same since ancient times. But two stars in the Big Dipper have a proper motion large enough such than in 100,000 years, the stars will no longer make a dipper shape. Until then, you can remember the names of the seven dipper stars in order from handle to cup by remembering this helpful advice for teens: “AM, ask mom. PM, dad”. The stars are Alkaid, Mizar, Alioth, Megrez, Phad, Merek, and Duhbe. The Big Dipper is one fist held upright and at arm’s length above the north horizon at 11 p.m.

Sunday: To the people of Ancient Greece, the stars that are about five and a half fists above the east-northeast horizon at 10 p.m. were known as Cassiopeia and Andromeda, a mythological queen and her daughter. But not all cultures imagined the same pictures in the sky. To the people of Polynesia, the stars of Cassiopeia and Andromeda represented a dolphin, called Kwu. Cassiopeia formed its tail, the brightest stars of Andromeda formed its fins, and its fainter stars outlined the dolphin’s body.

Monday: Three planets are crowded around the setting Sun. Venus, the brightest, is one fist above the southwest horizon. Saturn is about a fist and a half to the right of Venus. Mercury is below Saturn, just barely above the horizon.

Tuesday: Uranus is in opposition tonight. That doesn’t mean that Uranus is in the minority party in the senate. Opposition means that Uranus 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. Uranus is about four and a half fists above the south horizon at 1 a.m. It is three and a half fists above the southeast horizon at 10:30 p.m. You’ll need binoculars to find it. First find Deneb Kaitos, the brightest star in the constellation Cetus the sea monster, one and a half fists above the southeast horizon. Deneb Kaitos is the same brightness as the North Star. If you imagine the distance from the horizon to Deneb Kaitos as one unit, move your binoculars straight up from southwest two more of those units. Uranus will be in the center of your field of view. Check that same spot over the next few night. Uranus will move slightly with respect to the distant stars.

Wednesday: Mars is about to get eaten by a lion, a constellation lion. It is right in front of the head of Leo the lion, three fists above the east horizon at 6 a.m.

Thursday: Keep an eye out for Jupiter which is slowly creeping into the pre-midnight sky. Tonight it rises at about 11:45 p.m. By 12:30, it is a half a fist above the east-northeast horizon.

Friday: The constellation Orion is four fists above the south horizon at 6 a.m. The Orion is a cloud of gas and dust visible with binoculars about a half a fist below the “belt” of three stars. If you are feeling especially attracted to the nebula, that might be because astronomers think there may be a black hole in the middle. They have not directly observed the back hole, which would be the closest known one to Earth at a distance of 1,300 light years. But the motion of stars in the region is consistent with them being near a black hole 100 times the mass of the Sun. For more information, go to http://goo.gl/AGjFf.

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

The Ellensburg sky for the week of 9/21/13

Saturday: “You know Aries and Cancer and Draco and Libra. Leo and Pisces and Virgo and Hydra. But, do you recall, the pointiest asterism of all? Triangulum, the three sided asterism, had a very pointy edge….” Sorry. Some stores have started putting up their Christmas decorations and that has put me in the mood to modify some Christmas songs. Anyway, Triangulum is a small constellation between the more prominent Andromeda and Aries. Its main feature is a skinny triangle oriented parallel to and nearly four fists held upright and at arm’s length above the east horizon at 10 p.m.

Sunday: At precisely 1:44 p.m. PDT, the center of the Sun crosses the celestial equator and passes into the southern sky. The celestial equator is an imaginary line that divides the sky into a northern and southern half. When the Sun is in the southern half of the sky, it appears to take a shorter path from rising to setting. It also does not get as high in the sky at noon. This leads to shorter days and longer nights. Since the Sun crosses the celestial equator today, there is an instant when it is equally in the northern and southern sky, called the north and south celestial hemispheres. This so-called “equal night” is given by the Latin word equinox. Thus, today is known as the Autumnal Equinox. However, the day and night are not of equal duration today. The sun rises at 6:50 a.m. and sets at 6:58 p.m. Day and night are closest to equal duration on Tuesday.

Monday: “My laddie, you’re a wee bit close to that launch” is what a stereotypical Scottish person may have said to a frog that watched the recent launch of the Lunar Atmosphere and Dust Environment Explorer. The spacecraft, abbreviated LADEE and pronounced “laddie”, was launched on September 6. A remote NASA camera captured an image of a frog jumping at the same time the rocket blasted off. Read more about the launch, and more importantly, the frog at http://goo.gl/YrwkpU. LADEE’s mission is to study the moon’s very thin atmosphere and conditions near the moon’s surface.

Tuesday: To celebrate the start of school at CWU tomorrow, let’s sing a song of the season. “Oh the weather outside is grand. And the fire is rightfully banned. There is really no place to go. Let it snow, let it snow, let it snow. On Mars.” The Mars Reconnaissance Orbiter has discovered evidence of carbon dioxide snow clouds high above the surface of Mars.  Carbon dioxide, also called “dry ice”, exists in Mars south polar ice cap and requires temperatures of nearly 200 degrees below zero Fahrenheit to form. Astronomers were not sure how this polar cap gets replenished but the discovery of carbon dioxide clouds may provide an answer. For more information, go to http://goo.gl/shMTf. Mars is three fists above the east-southeast horizon at 6 a.m. The weather is certainly not grand on Jupiter, which you can find five and a half fists above the southeast horizon at this time.

Wednesday: Did you time the exact length of the day and night on Saturday, the first day of autumn? They were not equal in duration. Many people think that the day and night are the same duration on the autumnal equinox. The day is a little longer than the night for two reasons. First, the Sun is an extended object so even when the middle part has set, the upper half is still above the horizon lighting the sky. The second, and more influential reason is that the atmosphere acts like a lens, bending light from the Sun above the horizon when the Sun is really still below the horizon. Day and night are closest in duration today.

Thursday: The bright bluish star Vega is nearly straight overhead at 8 p.m.

Friday: The cloudy season is coming to Ellensburg. Don’t feel bad. According to astronomers from the European Southern Observatory, it is always cloudy season on HD 85512b, a newly discovered planet orbiting the star called… wait for it… wait for it… called HD 85512. These astronomers developed a method to estimate the cloud cover on planets orbiting distant stars. They think HD 85512b may be cloudy enough to have liquid water on its surface even though it is fairly close to its host star. While the presence of surface water does not guarantee finding life, it is a critical component. For more information, go to http://goo.gl/bGxMD.

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

The Ellensburg sky for the week of 9/14/13

Saturday: “Excuse me, do you have the time?”

“No, but the Big Dipper does.”

You can use the orientation of the Big Dipper to tell time with a precision of about 15-30 minutes. First, find the two stars at the far end of the Big Dipper cup, the stars that do not touch the handle. Draw an imaginary line segment starting at the North Star and passing through the two Big Dipper cup stars. Now, draw a big circle around the North Star. Your circle is a 24-hour clock. Number the circle from 0 hours at the top, counterclockwise to 12 hours at the bottom of the circle, and back up to 24 hours at the top. (O hours and 24 hours are the same on this clock because the day is 24 hours long.) The hour number on the big circle closest to where your imaginary line intersects this circle is called your raw time. Due to the location of the Big Dipper compared to the rest of the stars, the time nearest the intersection (the raw time) is correct for March 6. For any other night, subtract two times the number of months the current date is after March 6 from the raw time. For example, let’s say the imaginary line between the North Star and the Dipper stars is pointed to the right. That means the raw time is 18 hours or 6 p.m. If you made this observation on October 6, which is seven months after March 6, you would subtract two times seven or 14 hours from the raw time.  Thus, the time for November 6 is 18 hours minus 14 hours or 4 hours. In other words, 4 a.m. Don’t forget to convert for daylight savings time if needed. For a more complete set of instructions, go to http://goo.gl/02HmA. There is a simple “star clock” template and instructions at http://goo.gl/SFKrE. Use this paper star clock whenever you watch is broken.

Sunday: Venus and Saturn are close together in the early evening sky for the next few days. At 8 p.m., Venus is about a half a fist held upright and at arm’s length above the west-southwest horizon. Saturn is less than a half a fist to the upper left of Venus. Over the next few evenings, Saturn will move down toward Venus in the sky.

Monday: Let me tell you the story of the ghostly white figure that rises early in the morning in early autumn. It appears to be a huge dim glow of white light that rises up from the east in the pre-dawn sky. No, I’m not writing about the ROTC student who has early morning physical training. I’m describing 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 sky with no haze or light pollution to see the zodiacal light that will be visible for the next few weeks or so. At its brightest, the zodiacal light rivals the light of the central Milky Way.

Tuesday: If you stay up late, you can see Jupiter rising just before 1 a.m. If you get up early, say 6 a.m., you can see Jupiter five fists above the east-southeast horizon and Mars three fists above the eastern horizon.

Wednesday: Shine on, shine on harvest moon, up in the sky. It’s just like a full moon in January, February, June and July. The only difference is that near the Autumnal Equinox (also known as the first day of fall), the full moon rises close to sunset resulting in a full night of light for the harvest. The harvest moon looks more orange than usual when it is near the horizon because of the dust kicked up from the harvest. The dust scatters the white light reflecting off of the Moon resulting in slightly more of the red and orange components of the white light reaching your eyes. Although the Moon has a dull yellow color whenever it is near the horizon owing to light scattering off of dust and atmospheric particles, the effect is more noticeable for the harvest Moon. Tonight’s full moon, which isn’t completely full until tomorrow at 4 a.m., is in the constellation Pisces the fish. For more information about the harvest moon, go to http://earthsky.org/space/harvest-moon-2.

Thursday: “One world, group hug, love everyone” philosophy: political borders are human-made and can’t be seen from space. Real world, pragmatic discovery: some human-made political borders CAN be seen from space. Since 2003, India has illuminated its border with Pakistan to prevent illegal crossings. In August, astronaut Ron Garan took a picture of the boarder from the International Space Station. For more information, including the photo, go to http://goo.gl/mY8xG.

Friday: Sirius, the brightest star in the nighttime sky, is two fists above the southeast horizon at 6 a.m.

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

The Ellensburg sky for the week of 9/7/13

Saturday: Are you an early morning riser? If so, get up at 5 a.m. tomorrow morning and look two fists held upright and at arm’s length above the east horizon. Mars is in the Beehive Cluster, an open cluster of about 600 stars, all about 600 light-years from Earth. If you were standing on Mars, the Beehive cluster would not look any different because being “in” a celestial grouping just means being in line with that grouping as viewed from Earth. But if you were standing next to the Mars Curiosity Rover on August 17, you would have seen Mars’ moon Phobos eclipse the Sun. Since Mars tickets are difficult to acquire, NASA made a short video for you http://goo.gl/79sr59.

Sunday: Geometry review, part 4. Previously in this column, we have reviewed triangles. You’re feeling pretty confident about the definition of a triangle, aren’t you? But do you know what an obtuse triangle is? At 8 p.m., the moon, Venus, and Spica will make a small obtuse triangle about a half a fist above the west-southwest horizon. A triangle where one of the interior angles is greater that 90 degrees is called obtuse.

Monday: Science is Central! This week, faculty, staff, and students in the College of the Sciences at CWU will kick off the start of the academic year by hosting a series of evening science lectures and demonstrations geared for all ages. All events are taking place on the CWU Ellensburg campus and all are free. The series kicks off tonight with CWU professor, astronomy club advisor and columnist extraordinaire Bruce Palmquist at 7:00 – 8:00 pm in Lind Hall 215 on the CWU campus. He’ll be doing and teaching demonstrations about electricity and magnetism. They’ll make you say, “Wow”, Ohhh”, and “Ahhh”. Go to http://www.cwu.edu/newmap.html for a map of campus. Parking is free after 4:30 p.m. For more information about the week’s events, go to http://www.cwu.edu/cesme/upcoming-events.

Tuesday: In most parts of the country, a mixture of tasty carbon-based material and healthy minerals is called a casserole. In Minnesota, it is called a hot dish. (Uffdah, you betcha!) In space, it is called a supergiant. Antares, a supergiant in the constellation Scorpius, is forging lighter elements into carbon, oxygen, silicon, and iron in its core. It is on the main course table one fist above the southwest horizon at 7:30. Make sure it cools off before you take a bite.

Wednesday: Saturn is one fist above the southwest horizon at 8 p.m. It is to the upper left of the much brighter Venus.

Thursday: In 1987, the rock group Def Leppard sang “Pour some sugar on me, in the name of love. Pour some sugar on me, come on fire me up”. In 2012, some European astronomers “found some sugar near stars, they were very young. Found some sugar near stars, out where planets formed.” Astronomers observed molecules of glycolaldehyde, a simple form of sugar, in the disk of gas and dust orbiting young binary stars. This is the first time astronomers have found this simple sugar so close to a star indicating that organic molecules can be found in planet-forming regions of stars. For more information, go to http://goo.gl/tfwy1.

Friday: Did you know that Friday the 13th is not a lucky day? “Beating the odds” is one definition of luck. Because of the pattern of the Gregorian calendar, Friday is the most common day of the week to be the 13th day of the month. Thus, when you encounter a Friday the 13th, you are not beating the odds because Friday is the most likely 13th day. The least likely day? A tie between Thursday and Saturday.

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