Thursday, April 23, 2015
Saturday: Tonight’s first quarter moon makes a right triangle with the Beehive Cluster and Jupiter. Since it is so close to the Moon in the sky, you’ll need binoculars to see the Beehive Cluster. First find the Moon at 10 p.m. Then look about a half a fist held upright and at arm’s length to the upper right of the Moon. The other corner of the triangle, Jupiter, is about a fist to the upper left of the Moon.
Sunday: Mercury is a half a fist above the west-northwest horizon and Venus is two and a half fists above the west horizon at 9 p.m.
Monday: Saturn is a half a fist above the southeast horizon at 11 p.m.
Tuesday: Do people think you have a magnetic personality? The star Cor Caroli understands how you feel. Cor Caroli has one of the strongest magnetic fields among main sequence stars similar to our Sun. This strong magnetic field is thought to produce large sunspots that cause the brightness of Cor Caroli to vary. Cor Caroli is nearly straight overhead at 11:30 p.m.
Wednesday: You know Metis and Thebe and Adrastea and Amalthea. Io and Ganymede and Callisto and Europa. But do you recall? There are 67 Jovian moons in all. (As of July 2013.) Just 60 years ago, Jupiter was thought to have only 12 moons. But, astronomers are red-nosed with delight that the advent of supersensitive electronic cameras has caused the number of discovered moons to rapidly increase. Jupiter’s 67 moons range in size from Ganymede, with a diameter of 5,262 kilometers, to S/2002 J12 and S/2003 J9, with a diameter of only one kilometer. Our moon has a diameter of 3,475 kilometers. (One kilometer is 0.62 miles.) Saturn is second place in the moon race with 62. Uranus is next with 27. Then comes Neptune with 14, Mars with 2, and Earth with 1. Even dwarf planets have moons. Pluto has 5, Eris has 1, and Haumea has 2. Eris is an outer solar system object that was discovered in 2005 and named in September of 2006. Because astronomers thought it was larger than Pluto, people called it the tenth planet for a while. (More recent measurements show Eris to be a little smaller than Pluto.) Haumea, the newest dwarf planet with a moon, was discovered in 2004 and officially named a dwarf planet on September 17, 2008. Jupiter, the “mooning” champ, is four fists above the west horizon at 9 p.m. Go to http://goo.gl/Xkoeq for more information about Solar System moons.
Thursday: Avast ye matey. Swab the poop deck. Pirates love astronomy. In fact, the term “poop” in poop deck comes from the French word for stern (poupe) which comes for the Latin word Puppis. Puppis is a constellation that represents the raised stern deck of Argo Navis, the ship used by Jason and the Argonauts in Greek mythology. Argo Nevis was an ancient constellation that is now divided between the constellations Puppis, Vela and Carina. The top of Puppis is about a fist and a half to the left of the bright star Sirius in the south-southwest sky at 9 p.m. Rho Puppis, one of the brightest stars in the constellation, is about one and a half fists above the south-southwest horizon at this time.
Friday: Winter must be over because the winter constellations are becoming less visible. Orion is setting in the west starting at about 9 p.m. At this time, Orion’s belt is a little more than half a fist above the west horizon and Betelgeuse is nearly two fists above the west horizon. By mid-May, Orion will be lost in the glare of the Sun.
Wednesday, April 15, 2015
Saturday: Venus is two and a half fists held upright and at arm’s length above the west horizon at 9 p.m.
Sunday: Tonight at 8 p.m., listen to an Eminem song. Next, eat some M & M candies. Finally, look one fist above the west horizon to see the Moon and Mars and Mercury side by side. Mars is less than a half a fist to the right of the Moon and Mercury is a half fist to the lower right of Mars. That’s right. Watch the sky’s own M and M and M while eating M & Ms while listening to Eminem. You’ll have a great time or my name’s not (what?). My name’s not (who?). My name’s not… Slim Shady.
Monday: Sirius, the brightest star in the night sky, is dipping lower and lower. (Do you like how I used the word “dipping”? Big Dipper. Get it? Never mind.) It is only a half a fist above the west-southwest horizon at 10 p.m.
Tuesday: 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 http://goo.gl/8sw3rM.
Wednesday: Remember the old saying: April showers bring… meteors. The Lyrid meteor shower peaks this morning and tomorrow morning. The meteors appear to come from a point to the right of the bright bluish star Vega in the constellation Lyra the lyre. This point is about three fists above the east-northeast horizon at midnight tonight and close to straight overhead near dawn. The best time to look is just before dawn since that is when the radiant, or point from which the meteors appear to come, is high in the sky. This year, the Moon is in the waxing crescent phase meaning it has set long before the prime viewing time. Typically, this is one of the least interesting major meteor showers of the year. However, it is also one of the most unpredictable. As recently as 1982, there were 90 meteors visible during a single hour. In addition, the Lyrid meteor shower has historical interest because it was one of the first ones observed. Chinese records say “stars fell like rain” in the shower of 687 B.C. As your Mother might say, dress warm and sit in a comfortable chair for maximum enjoyment. Meteors are tiny rocks that hit the Earth and burn up in the atmosphere. For more information, go to http://goo.gl/j87bVB.
Thursday: As the weather warms up, people start thinking about swimming in a nice cool body of water. Recently, astronomers have discovered evidence an ocean about 20 miles beneath the surface of Saturn’s moon Enceledas. NASA’s Cassini probe measured variations in how the moon’s gravity pulled on the orbiting spacecraft. These variations can be explained by a large amount of liquid water under one section of the ice because liquid water is denser than an equal volume of ice. While you need a very large telescope to see Enceledas, Saturn is one fist above due southeast at midnight.
Friday: Capella is a half a fist above the north-northeast horizon at 5 a.m.
Wednesday, April 8, 2015
Saturday: You probably didn’t know this but several British New Wave bands were really into astronomy. Take the band “Dead or Alive” (please). The original lyrics to their song “You Spin my Round (Like a Record) were thought to be: “ You spin me right round, baby, right round, like the Whirlpool Galaxy, right round, round, round.” (Well, that’s what I thought them to be.) The Whirlpool Galaxy was the first galaxy observed to have a spiral shape. Since then, astronomers have discovered many galaxies, including our own Milky Way Galaxy, have a spiral shape. Go to http://www.spacetelescope.org/images/heic0506a/ for more information about the Whirlpool Galaxy. Go to your small telescope to find the Whirlpool Galaxy in the night sky. It is in the constellation Canes Venatici, the hunting dogs. At 10 p.m., find Alkaid, the end star of the Big Dipper handle, six fists above the north-northeast horizon. The Whirlpool Galaxy is two fingers to the upper right of Alkaid.
Sunday: Venus, the Roman goddess of love, is hanging out with the Seven Sisters tonight. The sisters, also known as the Pleiades, are about a thumb thickness to the right of Venus. They are two fists above the west horizon at 9 p.m.
Monday: Do you want to inspire people to celebrate the beauty of the night sky? To raise awareness of the negative effects of light pollution? Then celebrate International Dark Sky Week by going to http://goo.gl/xc29se and taking action. I suggest clicking on “Outdoor Lighting” and then “Residential Lighting Guide” to see examples of more effective outdoor lighting. The best lighting for observing the night sky is also the best light for safety because effective yard light focus their energy on the ground, where it is needed, and not up into the sky.
Tuesday: Jupiter is six fists above the south horizon at 9 p.m.
Wednesday: The Lyrid meteor shower peaks next week. But there will be increased meteor activity for the next two weeks in the vicinity of the constellation Lyre. The meteors appear to come from a point to the right of the bright bluish star Vega in the constellation Lyra the lyre. This point is about three fists above the east-northeast horizon at midnight and close to straight overhead near dawn.
Thursday: The nighttime stars take little more than an instant to rise. The Moon takers about two minutes to rise. That’s absolutely speedy compared to the constellation Virgo, which takes four hours to rise. The first star in Virgo rises at 4:30 in the afternoon today. Spica, the brightest star in the constellation, rises at 7:30. By 9 p.m., Spica is one fist above the southeast horizon.
Friday: Mercury is about a half a fist above the west-northwest horizon at 8:15 p.m. The much brighter Venus is three fists above due west at this time. In between the two is Mars, about one fist above the west horizon.
Thursday, April 2, 2015
Saturday: The first day of spring was March 20. The most recent full moon was last week. That means tomorrow is Easter. The standard way to determine the date of Easter for Western Christian churches is that it is the first Sunday after the full moon that occurs on or after the vernal equinox, also known as the first day of spring. Of course, the other standard way is to look for the date of church services celebrating the resurrection of Jesus. There is no Bible story of an “Easter star”. If there were, Spica would be a pretty good choice. The name Spica comes from the Latin “spica virginis” which means “Virgo’s ear of grain”. Spica represents life-giving sustenance rising after a long winter just like the risen Jesus represents life-giving redemption to Christians. Spica is a half a fist held upright and at arm’s length above the east-southeast horizon at 9 p.m., just to the lower right of the Moon. For an algorithm on how to calculate the exact date of Easter for any year, go to http://goo.gl/gFnepP.
Sunday: Jupiter is six fists above due south at 9 p.m.
Monday: At 8:30 p.m., Mars is a half a fist above the west-northwest horizon and Venus is two and a half fists above the west horizon.
Tuesday: Vega is one fist above the northeast horizon at 10:30 p.m.
Wednesday: So far this week, I have written about Venus, Mars, and Jupiter. Do you like 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 http://www.pbs.org/wgbh/nova/pluto/favorite.html 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 at 6 a.m., two fists above the south-southeast horizon.
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 10:18 p.m. two Thursdays ago. Tonight, it reaches due north at 9:23 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.)
Friday: It you didn’t run the Yakima River Canyon Marathon two weeks 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 11:30 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/DWnhHL.
You better not party to hard on Friday night because you'll want to get up early Saturday morning for the total lunar eclipse. Or, maybe party very hard and stay up all night. The partial portion of the eclipse starts at about 3:15 am in Washington state. Totality occurs for a few minutes at 4:58 am. Go to https://youtu.be/_70M4lkLKPk?list=PL8F7BC3F1240213F5 for more information about the eclipse.