StarWatch for the greater Lehigh Valley

JULY  2017


Print Large Sky Charts For 10 p.m. EDT:   NORTH | EAST | SOUTH | WEST | ZENITH

[Moon Phases]
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Current Geomagnetic Field:  
Status Current Moon Phase
1089    JULY 2, 2017:   Satellite of Hard Knocks—The Moon
It’s hard for me to believe that one of the aspects of my enjoyment of the night sky that I had originally disliked—the moon, has now become an agreeable facet of my nightly inspections of the heavens. Its gossamer appearance bathed in ghostly earthshine when a razor crescent; Luna’s changing phases that are easy to discern; its rapid movement from night to night as it approaches and sometimes occults bright stars and planets; its sun like illumination under the photographic lens; and its ability to hide in the shadows of the Earth or court the sun to the exhilaration of the visual senses during a lunar or a solar eclipse, make it a joy to observe. The airless, nearly waterless moon has been with us almost since Earth’s formation. The early solar system was a rough and tumble place, laced with debris both large and small as the planets accreted. Some satellites undoubtedly formed in this leftover material orbiting around their parent planets. Others were captured, like the small moons of the outer giant planets and Mars, but our moon’s origin was probably different. Most planetary astronomers believe that a Mars-sized object sideswiped Earth, drawing material from our primordial crust and spraying it into space. Some of this matter went into orbit around the Earth and rapidly coalesced to form the moon. Other debris continued to bombard Luna, creating a completely crater saturated surface which today is called the highlands. Watch the moon as it blossoms this week towards its full phase. The lighter, more reflective areas of its terrain are still represented by this original crustal material dating to over four billion years in age. Other locales of the moon’s nearside are darker and more circular in nature, indicating another chaotic period of lunar history. Protoplanets thrown inward by the outer planets or perhaps a major breakup of the asteroid belt pummeled the moon’s surface about 3.85 billion years ago, gouging from its surface huge basins that were eventually inundated with lava gushing from its depths. This basaltic rock had a slightly different composition, and therefore, a different reflectivity. Today, we observe the basins called maria as the darker lowlands of Luna’s surface. They are dated to about 3-3.5 billion years of age. So, as you look at the moon this week, consider the fact that you are witnessing a chronological palette of events, billions of years in the making and right in front of your eyes, a history book frozen in time for you to see.

1090    JULY 9, 2017:   Three Planets on the Loose
Before it’s gone in just about a week, you might want to try your luck at viewing Mercury. It’s back again after 115 days, very low in the WNS after sundown. Unlike the last time it made an appearance in the west in late March, its orbital plane was tilted at a high inclination to the horizon. This time, Mercury’s orbit appears less inclined, causing its motion away from the sun to carry the Messenger God only a little bit higher in the sky each day. During the week, Mercury remains consistent in its altitude as well as its brightness, so this is not a one day event. What you’ll need, however, is an excellent western horizon, a clear evening, and a pair of binoculars. Be at your observing post about a half hour after sundown. Forty-five minutes after sunset, Mercury is at an altitude of only five degrees, about a half of a field of view through an average pair of binoculars. Any starlike object appearing very low in the west will be Mercury. If Mercury proves elusive, Jupiter will be visible much higher in the SW at the same time. Its brightness will be about twice that of Mercury’s luminescence, but because of its much higher altitude, it will easily stand out against the deepening twilight. Although Venus is the brightest planet in the heavens and now visible in the east at 5 a.m., it is by no means the boldest. That title belongs to Jupiter, but you’ll need a small telescope to prove it. Even at low magnifications, Jove will not disappoint. Its four Galilean satellites, Io, Europa, Ganymede, and Callisto, discovered by Galileo Galilei in 1610 with a small refractor of his own making, will be readily visible if they are not blocked by the planet or are too close to each other. They change their positions from night to night, in fact from hour to hour and are one of the most enjoyable aspects of watching Jove. Focus carefully, and you may even catch the two prominent darker equatorial belts which girdle the planet. These are regions of downdraft, where the atmosphere is colder and denser, only to be warmed at depth to rise again in the lighter zones of the planet’s cloud tops. Finally, don’t miss Saturn low in the SSE. It is bright, but not overpowering because of its altitude and lies about 15 degrees to the left of Antares, the super red giant star of Scorpius the Scorpion. Once you’ve locked onto yellowish Saturn, even at low magnifications, you’ll see the rings fully opened and magnificent and understand why the Harvest God is judged the most beautiful planet in our solar system.

1091    JULY 16, 2017:   Ripples in Time
SUSAN: In soft summer evenings of long ago, pale twilight deepens as the streetlights bloom with yellow halos. The heat of the day dissipates, and on one such occasion, the neighborhood kids get a chance to see far beyond the lights of their city to an alien world. Behind the sleepy street where lights in houses shine warmly, a man sets up a telescope. He was an anomaly. No one I knew had a telescope much less looked through one, but there he was in the alley with this scope. What was singular was that he allowed us all to have a peek. To me that was exiting—to see a planet, Saturn no less, and it wasn’t in a book or on TV. It was like a tiny detailed toy hanging by an invisible string in the blackness of space. From this urban locale, it was difficult to see anything noteworthy, but with his expertise, he had found Saturn to the delight of us all. Sometimes small events can cause ripples, and as such, they can carry their motions and effects forward, long after their creation has passed. I found myself getting interested in astronomy which led me to tell a high school friend who was also involved in sky watching, about my experience much later. That led to our going to a local astronomy club, the Lehigh Valley Amateur Astronomical Society, where I heard another student speak on meteor showers and how to observe them. Years later at the same club, I saw the same person, now a man, giving a lecture on the moon. I ended up marrying him nearly four years later. So that anonymous neighborhood man began something in my life that influenced it ever after, in a sense like a ripple in time seeking its shore.
GARY: I remember that night well, in July of 1969 a skinny, rising sophomore at Kutztown University, interested in becoming an educator, director of the junior contingency of LVAAS, giving his first formal presentation to senior members of the club. I was dressed in a coat and tie—nervous, but the talk went well, and afterwards a group of individuals gathered around me to ask more questions. My future wife was in that small audience. Years later, when I arrived for my presentation on the moon, unknowingly, she was the woman that I chose to sit behind before being introduced to speak, and she was also in the small group of people that gathered to query me afterwards. In a very serendipitous way, our ripples in time connected and amplified on that evening of October 3, 1978, and nearly four decades later, now married to my Susan for 35 years, I can honestly say that it was the best moment of my life.

1092    JULY 23, 2017:   Bat in a Hat
It is one o’clock in the morning, and it’s not even time for bed. I’m at the Mars Desert Research Station near Hanksville, Utah and participating in the construction of the new robotic observatory which Moravian has a 25 percent share in time usage. I’m tired and thirsty. I’m also sitting on the “throne” in our luxurious “state of the art” bathroom facility which is simply an adapted RV toilet. It you don’t have to reinvent it, why not use what’s available? Suddenly, and I mean suddenly, the largest moth that I have ever seen in my entire life flutters down within inches of my face and lands on the floor. I notice that its wings have bones in them so I immediately realize that it’s a bat. It doesn’t want to be there in company with me, and frankly, I’d like to see it depart. I’m not primo bat food, you know. I reach forward, crack open the door, and hope that it will see its escape (bats are not blind), move in that direction, and find insects elsewhere. It does precisely as I predicted, but as I’m closing the door and regaining my sense of composure, I realize that all the other doors in the MDRS facility are shut too. So now we’ve got a bat in a hat—actually, in a large tin can. That was enough excitement for one evening. The bat found a place to hide; I eventually finished my assignments, then navy showered, and went to bed, immediately falling into a deep sleep in my small cubicle on the upper deck. Suffice to say that living on Mars in the Utah desert has its exciting moments, but it also has some of the darkest skies in the US; and if you’re an astronomer, you’ll take the occasional surprises for the nighttime bliss. [Literally, as I’m writing this, a gust of wind just knocked out the window of our front door. Fixed it!] There is an ecosystem flourishing under the habitat that we rarely get to see, but it’s there. No snakes or scorpions yet, but an occasional rodent makes its way inside, including bats, and a very lost and hairy tarantula that greeted my buddy, Pete, on a bathroom run several years ago. Unfortunately, after numerous attempts at extrication, it did not get the chance to grow old. The biggest problem this year has been the heat. The MDRS is not air-conditioned. Days are hot with highs in the low hundreds, but the nights are pleasant with temps in the upper fifties to low sixties. Fans pump enough cool air into the facility during the evening hours to create pleasant sleeping conditions and make the days almost bearable. Our record indoor high this trip was 99.1 degrees F. Hydration is essential with humidity levels under 15 percent. More about “life on Mars” next week.

1093    JULY 30, 2017:   

[July Star Map]

[July Moon Phase Calendar]