Thursday, September 25, 2014

The Ellensburg sky for the week of 9/27/14

Saturday: Saturn is about a finger-width to the upper left of the moon at 8 p.m., very low in the west-southwest sky. Viewers in Hawaii will get to see the moon pass between Saturn and the Earth at about this time. The blocking of one celestial object by another is called an occultation. The group that sang, “Burnin’ for You” is Blue Oyster Cult.

Sunday: 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.

Monday: 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.

Tuesday: Aldebaran, the bright orangish star in the constellation Taurus, is one fist above the east horizon at 11 p.m.

Wednesday: Can’t sleep? Get up early and watch the largest planet in the Solar System and the brightest star in the night sky rise at the same time: 2:18 a.m. By 3 a.m., Sirius will be a half a fist above the east-southeast horizon and Jupiter will be a half a fist above the east-northeast horizon. By 3:05 a.m., you may return to bed.

Thursday: 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

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. Are you are feeling especially attracted to the nebula? If so, that might be because astronomers found evidence of 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. For up to date information about the night sky, go to https://nightsky.jpl.nasa.gov/planner.cfm.


Thursday, September 18, 2014

The Ellensburg sky for the week of 9/20/14

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: There is a rumor (started by my dog and me) that The Beach Boys are working on a new solar system-themed record. I bet the first single will be “Catch a Wave and You’re Sitting on Top of Titan.” As the seasons change on this large moon of Saturn, astronomers are looking for signs of the winds increasing. They’ll send the Cassini spacecraft on a flyover of Kraken Mare, a large liquid hydrocarbon sea, to see if there are any waves. The NASA Jet Propulsion Laboratory has made a “Titan Great Lakes” tour video that you can find at http://goo.gl/ndXDhd. Available lakefront property and the potential for large waves. Who is up for a “Surfin' Safari”? Saturn is one fist above the southwest horizon at 7:30 p.m.

Monday: At precisely 7:29 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 6:48 a.m. and sets at 7:02 p.m. Day and night are closest to equal duration on Friday.

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 one fist above the south-southwest horizon at 7:30 p.m., just to the upper right of Antares, which means “rival to Mars”. Or as Mars calls it, “rival to me”.

Wednesday: Are you ever thirsty at midnight? The Big Dipper is low on the northern horizon at midnight, just waiting to hold water for you.

Thursday: Jupiter is about three fists above the east horizon at 6 a.m.

Friday: Did you time the exact length of the day and night on Monday, 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 lower half 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 below the horizon. Day and night are closest in duration today.


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 https://nightsky.jpl.nasa.gov/planner.cfm.

Wednesday, September 10, 2014

The Ellensburg sky for the week 9/13/14

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 explanation on how to do the Big Dipper clock math, go to http://goo.gl/02HmA. If you prefer a more visual tool, and a fun project to do with your kids, 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: Aldebaran, in the constellation Taurus, is about one fist held upright and at arm’s length above the east-northeast horizon at 11:30 p.m.

Monday: The last quarter moon rises a little before midnight and is in the constellation Taurus, moving into Orion by the morning.

Tuesday: At 8 p.m., Saturn is one fist above the west-southwest horizon. It seems to be having a carefree existence in the constellation Libra. Mars, on the other hand, is being forced to spend time with its rival in the constellation Scorpius. Because the brightest star in Scorpius was a similar color and brightness as Mars, it was given the name Antares which means “rival to Ares”, the Greek god of war. Since Mars was named after the Roman god of war, Antares can also be interpreted to mean “rival to Mars”. They are close together in the sky tonight and for the next two weeks. Both are about one fist above the south-southwest horizon. Mars is the brighter of the two and is slightly redder than Antares. Mars is also farther west, closer to Saturn.

Wednesday: Stuart Sutcliffe was the fifth Beatle. d’Artagnan was the fourth Musketeer. Ophiuchus is the thirteenth constellation in the Zodiac. The Zodiac consists of all the constellations that the Sun appears to line up with as the Earth’s celestial perspective changes throughout its annual orbit. You know twelve constellations in the Zodiac because they are the 12 horoscope signs. But the Sun also lines up with Ophiuchus for about two weeks every year. You can spend some time with Ophiuchus tonight. The center of the coffin shaped group of stars is four fists above the southwest horizon at 8 p.m.

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: Jupiter is less than a fist above the waning crescent moon. The bright star Regulus is about a fist and a half to the lower left of the moon.


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 https://nightsky.jpl.nasa.gov/planner.cfm.

Wednesday, September 3, 2014

The Ellensburg sky for the week of 9/6/14

Saturday: Mars and Saturn are each about a fist and a half held upright and at arm’s length above the southwest horizon at 8 p.m. They are so interesting to look at. If only there was an opportunity for you to see them through a telescope….

Sunday: 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 presentations geared for all ages. All events are taking place on the CWU Ellensburg campus and all are free. The series kicks off Tuesday night with a tour of the CWU greenhouse from 7:00 to 8:00 pm. The greenhouse is located on the west side of Dean Hall just north of 11th Avenue and D Street. From 8:00 to 9:00 p.m., move to the east side of Dean Hall to observe and learn about the night sky by looking through some of CWU’s telescopes. 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.

Monday: 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 is also a Super Moon, meaning it is near its closest point to Earth for the month. For more information about the harvest moon, go to http://earthsky.org/space/harvest-moon-2

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: At 6 a.m., Venus is a half a fist above the east horizon and Jupiter is two and a half fists above due east.

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: Tonight is date night. You could spend a lot of money on dinner and gift. But there is no guarantee of a reward afterward. By “reward”, of course I mean learning something new. For date night, go to Lind Hall 104 on the CWU campus from 7:00 to 8:00 p.m. to learn about volcanoes. For the “reward”, take your date to a dark place, the top of Lind Hall, and cuddle up… with a telescope for a tour of the night sky. Go to http://www.cwu.edu/newmap.html for a map of campus. Parking, and learning, is free after 4:30 p.m.


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 https://nightsky.jpl.nasa.gov/planner.cfm.