The Ellensburg WA sky for the week of 10/1/16

Saturday: Since Halloween is later this month; the stores are filled with bags of candy clusters. Instead, take time to look at a star cluster. The Hyades cluster is an open star cluster that represents the V-shaped face of Taurus the bull. It is one of the biggest and nearest star clusters with about 200 stars 150 light years away. The Hyades cluster was the first cluster to be the subject of detailed motion studies. These studies allowed astronomers to pinpoint the distance to the Hyades and provide important information about the scale of the universe. Aldebaran, nearly two fists held upright and at arm’s length above the east horizon at 11 p.m., is a foreground star and not a part of the Hyades cluster.

Sunday: Mercury is a half a fist above due east at 6 a.m.

Monday: 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.

Tuesday: At 7 p.m., Venus is a half a fist above the southwest horizon. It’s the brightest object in that part of the sky. Saturn is two fists to the upper left of Venus, nearly one and a half fists above the southwest horizon. Finally, Mars is one and a half fists above the south-southwest horizon.

Wednesday: Winter is coming to the morning sky. The “winter constellations” such as Orion, Taurus, and Gemini are high above the southern horizon at 6 a.m. They are called winter constellations because they are high in the sky during the evening viewing hours of the winter months.

Thursday: The last two columns described liquid methane on Saturn’s moon Titan and a possible liquid water ocean beneath the surface of Saturn’s moon Enceladus. But the most exciting water proclamation came last week when astronomers announced the presence of 125-mile long plumes of water shooting up from cracks in the ice on Jupiter’s moon Europa. It’s been long thought that Europa has an ocean under many kilometers of ice and that this ocean is one of the most promising places in the Solar System to harbour life. Instead of sending a lander to drill through the think ice, astronomers can send a much easier to design probe to catch and analyze the water from space. For more information about Europa’s water plumes, watch the video at https://youtu.be/4QJS9LcB66g.

Friday: The Draconid meteor shower peaks tonight and tomorrow night. The meteors appear to come from a point in the head of Draco, the dragon constellation. This point is nearly straight overhead at 7 p.m. tonight. This point remains near the trapezoid-shaped head of Draco throughout the night. Unlike most meteor showers, this one is best observed in the early evening rather than after midnight. Call this the “early to bed” meteor shower. Draconid meteors are slow moving which means you will have a easy time differentiating true Draconid meteors, from Comet 21P/Giacobini-Zinner, from stray grains of dust that happen to enter the Earth’s atmosphere near where we see the constellation Draco. The moon will be in the waxing crescent phase, near the south-southwest horizon, at peak viewing time so this might be your lucky meteor watching time. For everything you need to know about the Draconid meteor shower, go to http://goo.gl/HGkw0w.

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.

The Ellensburg, WA sky for the week of 9/24/16

Saturday: Last week you hung out on Titan’s lakes and dunes. Now dream about Enceladus’ ocean. Wow, that’s a lot of liquid in the Saturn moon system. Titan’s lakes are made of methane. But astronomers think there is a liquid water ocean beneath the icy surface of Enceladus.  Read all about it at http://goo.gl/6E0sHp. Saturn and its moons are one and a half fists held upright and at arm’s length above the south-southwest horizon at 7:30 p.m.

Sunday: Did you time the exact length of the day and night on Thursday, 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 actually below the horizon. Day and night are closest in duration today.

Monday: Jerry Seinfeld gave his best friend some good advice to see Mars this week: “You’ve got to go downtown George. Just like the song says.” Just like the downtown, or core, of a distant city has a glow from human-made light, the “downtown”, or core of the Milky Way galaxy has a glow from starlight. And this week, Mars is lined up right in the middle of this glow; one and a half fists above the south-southwest horizon at 8 p.m. Read more about the glow at https://goo.gl/3IVGcy.

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

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 morning to observe Mercury for the next few weeks. Mercury is nearly a fist above due east at 6:15 a.m. Over the next few weeks, Mercury will move toward the Sun in the sky. By early December, it will be visible in the evening sky.

Thursday: 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.

Friday: The moon almost directly between the Earth and Sun today. That means you won’t be able to see it. But that does not mean it doesn’t exist. Contrary to the belief of toddlers and immature politicians, just because you can’t see something doesn’t mean it doesn’t exist. (Note a double negative statement followed by a triple negative statement. I’m not unsorry about that.) Now, back to the science. What would happen to the earth if the moon really didn’t exist? In that 2013 blockbuster Oblivion, aliens destroy the moon and Tom Cruise survives. But the long-term effects on the earth would be devastating to life, as we know it. The moon stabilizes the spin axis of the earth keeping the seasons fairly uniform over time. For more information on what would happen to the earth if the moon were destroyed, go to http://goo.gl/4EbzLa. For more information on Thomas Cruise Mapother IV, go to http://en.wikipedia.org/wiki/Tom_Cruise.

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.

The Ellensburg WA sky for the week of 9/17/16

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 sending out their Christmas catalogues 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: Venus is about a half a fist above the west-southwest horizon at 7:30 p.m. If you use binoculars, you may be able to spot the bright star Spica right below it.

Monday: 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 “Surfin’ Titan” with lyrics such as “If everybody had an ocean, across Saturn’s moon. Then everybody’d be surfin’ and hanging out on the dunes. Saturn’s largest moon, Titan, doesn’t have an ocean. But it has Kraken Mare, a large liquid hydrocarbon sea as shown in the video that you can find at http://goo.gl/ndXDhd. And it has dunes in a region called Shangri-La shown here: https://youtu.be/P0RbbNb8Pns. Who is up for a “Surfin' Safari”? Saturn is one and a half fists above the southwest horizon at 8 p.m.

Tuesday: To celebrate the start of school at Central Washington University tomorrow, you could take a quick trip to Mars. How about America’s desert Southwest? Not enough time? Then just look at some photos from… from…. Hmmm. The photos at https://goo.gl/Elx7O8 look like they could be from either place. The Murray Buttes region of Mars, where the Curiosity rover has been exploring, look a lot like the landscape of Utah. So much so that the Mars-based movie John Carter was filmed there. Look for John Carter at your local video store. (“What’s that?” said the child.) Look for Mars one and a half fists above the south-southwest horizon at 8 p.m.

Wednesday: Do you see something small and twinkling about one fist above the east-northeast horizon at 10:30 p.m.? Your eyes are not playing tricks on you. That’s the open star cluster called The Pleiades making its way to the evening sky. It looks like a tiny measuring cup on its side.

Thursday: At precisely 7:21 a.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 6:49 a.m. and sets at 6:58 p.m. Day and night are closest to equal duration on Sunday.

Friday: According to “One world, group hug, love everyone” philosophy, political borders are human-made and can’t be seen from space so why can’t we all just get along. According to real world, pragmatic discoveries, some human-made political borders CAN be seen from space. Since 2003, India has illuminated its border with Pakistan to prevent illegal crossings. In 2011, astronaut Ron Garan took a picture of that border from the International Space Station. For more information, including the photo, go to http://goo.gl/mY8xG.

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.

The Ellensburg WA sky for the week of 9/10/16

Saturday: Today: “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: The calendar says summer is nearing an end. School starting says summer is nearing an end. The summer triangle in the sky begs to differ, as it is still high in the sky. Vega, the brightest star in the triangle, is a little bit west of straight overhead at sunset. Deneb is a little bit east of straight overhead and Altair is five fists above the south horizon.

Monday: Venus is about five degrees above the west horizon at 7:45 p.m.

Tuesday: Fomalhaut, the southernmost bright star visible from the northern USA, is one fist above the south-southeast horizon at 11 p.m.

Wednesday: 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. This stellar casserole is about one fist above the south-southwest horizon at 9 p.m. Mars, the brighter and tastier side dish, is about a fist to the upper left of Antares. Saturn, the ringed dessert, is less than a fist above Antares.

Thursday: 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 three fists above due southwest at 9 p.m., right above the Mars-Saturn-Antares triangle.

Friday: 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 nearly 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/?p=4162. Tonight the Moon passes through the partial shadow of the Earth, leading to a barely noticeable penumbral lunar eclipse.

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.