APRIL  2013

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I thought Comet PanSTARRS was fading, but this image taken on the moonlit night of March 23 at 8:23 p.m. still indicates that the comet is putting on a very nice show. The twilight hour was still cold, around freezing, but the wind was gone. An equatorially mounted Canon 60D camera and Canon 24-70mm zoom lens were used at an EFL of 96mm. The sensor was set to a color temperature of 4000K to help correct for light pollution. Two 10 second images at F/3.2, ASA 800, one with the drive engaged and the other with the drive stopped (to capture the trees in better focus) were combined and color corrected into one image. Gary A. Becker photography from Coopersburg, PA...

868    APRIL 7, 2013:   Smiley Moon, Smile Down on Me

There is a curious observation of the moon that is best seen in the spring nearest to the vernal equinox. I call it the “smiley moon.” It originated several years ago from a quip made to me by a woman from church who had said that she had seen one several nights previously. My conversations with friends are often laced with comments about odd things that they have seen in the sky at some point in their lives. Actually, before my readers become too judgmental, I need to say that I actually enjoy these types of chats because many times, I get the opportunity to explain the observations, and sometimes buried within what was seen is a real “diamond in the rough.” Such was the case with the smiley moon. Later that evening, my wife and I were catching a program on the tube. Our picture window faces west and through the gauzed curtains, I could see a horned moon that had a wide grin just like a Halloween pumpkin. I made two imaginary dots above it, and voila; there it was, the smiley moon about which I had just heard. I remember getting up and simply going outside, my hands on my hips, thinking something like, “You’ve been watching the moon all of your life, Gary, and you never put that together?” And the explanation was so simple. In the spring, the plane of the Earth’s orbit, which represents the sun’s path and very nearly the moon’s path in the sky, is tilted at a steep angle to the horizon. As the moon pulls up and away from the sun after its new phase, the crescent which forms from the sun’s light reflecting from the moon is nearly parallel to the horizon, creating the smile. On Saturday, April 13, about 45 minutes after sundown, look for a smiley moon between the “V” of Taurus the Bull’s head and the Seven Sisters. Binoculars will make the view more enjoyable. The next day, the moon with an even bigger grin appears to the left of brilliant Jupiter. Have some smiley fun with the smiley moon!

Behold, the Smiley Moon. The thin crescent moons during the several months surrounding the vernal equinox are pitched in such a way that a little imagination can turn them into moons with smiles. Earthshine, light from a nearly full Earth reflected back to us from the unlit portion of the moon helps with the face in this February 19, 2007 image taken from Coopersburg, PA. Venus can be seen below the moon near the horizon. Gary A. Becker photography...

869    APRIL 14, 2013:   More Than Meets the Eye

I’m just going to say it, “Spring is in the air,” regardless of the cooler than normal weather that many of us have been experiencing. It is obvious that the higher sun angles are at least warming the ground and the causing the buds and bulbs to stir. Despite the chilly conditions, the summer forecast from June through August calls for above average temperatures with normal precipitation. One aspect of spring, the sky, is always consistent. It is right on cue with the vernal patterns beginning to dominate in the east. An hour after sundown, look northeast, mid-sky, and you’ll notice the Big Dipper, cup up and handle down, beginning its slow tilt into its late spring upside-down position. The Big Dipper is not an official constellation, but it is certainly American friendly. It was never recognized by the International Astronomical Union, when in 1928, the IAU partitioned the sky into the 88 modern star patterns that we use today. When you view the Dipper, you are actually looking at part of a much larger grouping of stars called the Ursa Major Moving Cluster. Only the two end stars of the Big Dipper are not included. Astronomers know that the inner five were born from the same nebular cloud because they all have a common motion in space. Look at the middle star in the Dipper’s handle. That’s Mizar. If your vision is 20/20 and you are viewing from a suburban locale, a fainter star, Alcor, should be visible just below and to its left. Mizar and Alcor are thought to be a true gravitationally bound double, separated by a distance of 1.1 light years or 6.5 trillion miles. Alcor has an invisible red dwarf companion orbiting it, but Mizar, through the eyepiece of a small telescope, splits into two stars of almost equal brightness, making it one of the easiest doubles to observe. Each of those luminaries in turn is a double, bringing the Mizar-Alcor system to six stars in all.

870    APRIL 21, 2013:   Jupiter, Saturn, and an Eclipse

On the full moon day of April 25, there is a partial lunar eclipse, where the moon ever so slightly brushes into the shadow of the Earth. This eclipse will not be visible from anywhere in the United States, but most of Europe, Africa, Asia, Australia, and Antarctica will be able to see it. At maximum eclipse, which occurs at 4:07 p.m. EDT, the moon will protrude into the Earth’s shadow by less than 1.5 percent of its diameter. The entire event lasts for only 27 minutes. This is a really bad year for lunar eclipses, and I will have more to say about this situation when the most ephemeral of lunar eclipses bathes the eastern half of the United States around midnight on May 24. I am calling it “the eclipse that almost isn’t.” More importantly are two planets currently visible in the sky, one on the wane in the west, and the other emerging onto the scene in the southeast, both visible after evening twilight. Almost due west by 9 p.m. is mighty Jupiter, about one fourth of the way up in the sky, still “hanging tight” in Taurus the Bull. Jupiter has been in Taurus since mid May of 2012, and for a good part of that time near its alpha star, Aldebaran, the orangey eye of the Bull. Currently, Jupiter resides directly above Aldebaran. To the left and almost even with Jupiter is red supergiant Betelgeuse of Orion the Hunter, and even farther left and just slightly lower than Jupiter is Sirius the Dog Star, the brightest luminary of the night. Not quite as flashy will be Saturn, noticeable in the southeast by 10 p.m. Follow the arc of the Dipper’s handle, high in NE, to find Arcturus in Bootes the Bear Driver and then onward to blue white Spica of Virgo the Virgin. Saturn is to the left and below Spica and about the same brightness as Spica. The moon provides help on April 24 when it is located just over a degree from Spica. The following evening, the moon moves to a position just four degrees from the ringed world.

871    APRIL 28, 2013:   Beastie Dragon Draco

One of my favorite constellations of the northern sky is Draco the Dragon. In early May, its tail begins just under the bowl of the Big Dipper. The BD’s scoop and handle are nearly at their culminating (highest) positions in the north at 10 p.m. Then Draco’s tail curves downward over the cup of the Little Dipper and falls to the right of Polaris, the North Star. Following the sinuous tail of the Dragon is like trekking along on the winding Yellow Brick Road in the Wizard of Oz. The eye just seems to hop, skip, and tumble naturally from one star to another, but then there is a breakdown that occurs where the tail meets a small cadre of five faint stars that outline the tiny body of this fearsome sentinel. Where do you go from here? The secret during late April and early May is to look to the right and slightly above the five body stars to find an additional four stars that create a trapezoidal figure. That’s the head of Draco. By connecting the star of the head that is closest to the star of the body, the picture of Draco—tail, body, neck, and head—is completed. Some people see Draco as a turtle, camel, alligator or a snake. Whatever works for you is fine; however, for more than two decades, Draco has been my mystery constellation when I instruct classes under the real or electronic sky. I simply outline Draco’s stars without any comment and let my audiences guess at the pattern. Whether the group is composed of kindergarten kids or senior citizens, someone always, and I mean always, comes up with the Dragon. There has never been a miss. It gives credence to the concept that people separated by continents could have envisioned the same star patterns without any communications. You can download a sky map showing Draco’s current position by going to www.astronomy.org and clicking on “this week’s StarWatch.” Scroll to the top and click on the “North” sky chart for 10 p.m.