StarWatch: Moravian University Astronomy

MAY 2025

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1498 MAY 4, 2025: Eta Aquariids: Ghost of Halley's Comet: I am positive I have never written about the Eta Aquariid Meteor Shower because it favors the Southern Hemisphere, where variable rates fluctuate between 40 and 85 shooting stars per hour during a broad maximum that culminates on the mornings of Monday and Tuesday, May 5/6. That maximum continues through May 8. It is good to know that the Northern Hemisphere gets the bulk of meteor activity during the course of a year, balancing the more spectacular skies of the South and some truly spectacular comet apparitions that have occurred through serendipity, at least during my lifetime. However for Eta Aquariid displays, the East Coast is in a good location at 4 a.m. for seeing a few of these shooting stars. * Even on a non-shower night, meteor rates increase towards daybreak because the rotating Earth spins into the meteoroid debris. This condition is similar to a moving vehicle's front windshield being struck by more raindrops than its rear window during a rainstorm. This positioning will amount to more Eta Aquariid meteors seen. * Another interesting aspect of this shower is the dross making Eta Aquariids fly. It comes from the most famous comet of them all, Halley, now heading back from the sun from its current location beyond Neptune. Having passed its greatest distance from Sol (aphelion) in December 2023, it is due to be seen in 2061. Halley is currently in the spring constellation of Hydra the Water Serpent, moving towards the winter star pattern of Canis Minor the Little Dog. When it becomes visible to the unaided eye, Halley's Comet will produce a much better display than in 1986 when its positioning to the Earth and the sun placed it in the worst possible location since its first observation by Chinese astronomers in 239 BCE. * Because Aquarius is an autumn constellation and we are midway between spring and summer, the radiant, the location in the sky from which the meteors are diverging, does not rise until 3 a.m. On May 6 the moon sets at 3:15 a.m. Observers may begin to see a few Eta Aquariids grazing the upper atmosphere by 2 a.m., but any earlier viewing would be fruitless. I would recommend a 3-4 a.m. observing window or until dawn begins to interfere with observations. Then go back to bed if you can. By 4 a.m. the radiant, just under the jug that Aquarius is pouring water into the heavens, will only be 16 degrees above the ESE horizon. A locator map of the sky showing the location of the radiant can be found below. * Face south of east and focus your attention overhead, usually the darkest region of the sky, and if you see a meteor that trails back towards the ESE, you have most likely caught an Eta Aquariid. Expect no more than 5-10 meteors between 3 a.m. and dawn. By 4:45 a.m., when Venus, Neptune, and Saturn rise in the east, twilight conditions will drown most Aquariids from visibility. Much success in seeing the ghost of Halley's Comet this week, the Eta Aquariid Meteor Shower. Ad Astra!

1499

MAY 11, 2025: AI: You Still Need A Brain

When I started teaching in 1972, the slide rule ruled as the key calculator for solving mathematical problems. I used my dad's Keuffel & Esser in a black carrying case in high school and college in all of my science classes, and I was proficient with it. However, along came the handy battery-powered calculator, and shortly thereafter, the handy-sized rechargeable scientific calculator with its red diode display. My dad, who taught mathematics, and I were intrigued so much so, that we split the $350 ticket price to share one, but I got the better part of that deal. Meanwhile in the Allentown School District, there was an uproar ensuing in the high school science departments whether to permit students to use calculators or only slide rule computations. In my post-graduation Practical Astronomy class at Kutztown University, my professor, Dr. Carlson R. Chambliss, also purchased a scientific calculator for himself, and suddenly to the dismay of the other six students in the class, our assigned problems increased in difficulty by an order of magnitude. * Obviously, calculators won the day in Allentown science classes as they did everywhere, but there was an interesting tradeoff. Students quickly forgot that when they completed a problem with a calculator, they still needed to remain mentally active, solving a more simplified version in their heads, so the answer achieved by the calculator had some authenticity. Garbage in produced garbage out. * The other problem was significant numbers. The rule in multiplication (or division) is that the product can have no more significant numbers than the multiplier with the least significant figures. Therefore, the most accurate product of 365.2422 days/year x 2.13 years is 778 days, not 777.965886 because the 2.13 wins the day with the least number of significant digits, three. Slide rules never allowed the problem of significant numbers to become overbearing, but calculators did. * I see similar problems involving mental agility with Artificial Intelligence, but first the good points. For me, AI's help in writing this blog has been a game changer, especially since I began using Grammarly several years ago to cut down on syntax errors. My wife, Susan, a former English teacher, still proofreads my blogs and her final determinations outweigh Grammarly's, but I have noticed an improvement in my own language skills after submitting my weekly texts to Grammarly. The application grades your writing before suggesting corrections, and my raw scores have been getting better. I still have full control over whether to accept or reject the advice. So again, the use of AI with mental engagement still carries the day as with the use of calculators. * The problem that I see in letting AI rule the day, when you are not an expert in the information being gathered, is that you have no sounding board, no depth of knowledge, and no experiences to validate its authenticity. You may also be unaware whether AI is touting a particular influencing philosophy written into its software to target the user's opinions. That to me is scary. * When I Google a fact in astronomy and the AI-generated answer appears, I know almost instantaneously whether I can accept the entry or must continue to dig deeper using websites that I trust or my personal library of over 1000 books. You still must be mentally engaged in the process. That is not the case for a student taking my astronomy course at Moravian University and starting with a very limited knowledge of the science or sciences in general. They will commonly accept any information that scrolls across their screen as gospel. * I am frequently reminded of the feature film Contact. Near the film's climax, the protagonist, Eleanor Arroway (Jodie Foster), stands on the shoreline of a distant planet in a far-off galaxy, where she meets an alien disguised as her father. During their conversation, he says to her, "You're an interesting species, an interesting mix. You're capable of such beautiful dreams and such horrible nightmares." * Just like the scientific calculator, there is no doubt in my mind that AI is here to stay. So let us get on with a moral approach in trying to fix its shortcomings before the robots take over and put humanity out to pasture. Do you remember The Matrix? Difficult, yes; impossible, no! Ad Astra!

1500 MAY 18, 2025: StarWatch 1500: A Little History: This is my 1500th StarWatch, and a little history behind the column is in order. * StarWatch began in September of 1996 when Allentown's Morning Call newspaper approached the Lehigh Valley Amateur Astronomical Society, Inc., requesting a volunteer to write a weekly column. The MC no longer wanted to pay an outside vendor to produce their weekly astronomy column. No one responded. * I was contacted by the club's webmaster, Adam Jones, a former student and good friend, who suggested I use the column to provide publicity for the Allentown School District Planetarium, which I directed and which district officials were aggressively trying to close. This serendipitous spark ignited the StarWatch column, and most likely, was the most significant contributor in saving the Planetarium from closing through my retirement from public education in 2010. * I had already fought off numerous attempts by ASD officials to end the program, but the public had always rallied, carrying signs and forcefully speaking in support of keeping the stars shining for ASD pupils. To paraphrase the words of one woman who wanted the program to continue, I loved the Planetarium as a child and want my daughter to have those same opportunities. * I was also committed to public outreach because individuals living in an urban environment did not have the same prospects to view the heavens as individuals in rural and suburban locales. In addition, Allentown was a community with evolving demographics, with families moving into the area from urban centers. * One of the compromises that kept the ASD Planetarium operational was my raising of the yearly capital, about $10,000 to cover expenses, including the transportation of students to and from the facility. My salary and benefits were never in question. * Ironically at first, I had difficulty convincing the Morning Call that they should bond with the Planetarium, but when I submitted 30 weeks of short articles at their request, they relented, and StarWatch began appearing daily in their newspaper's weather section. Several years later, AccessWeather, Inc., began carrying StarWatch in several dozen weekly newspapers scattered across the country that subscribed to their weather service. * Major astronomical events, such as eclipses and the close approach of Mars in 2003, drew hundreds of local enthusiasts to field meets held at Dieruff High School and elsewhere across the Lehigh Valley, including Hawk Mountain. To my amazement, when I sponsored a trip to view a total solar eclipse near Aruba in 1998, advertising it through StarWatch and my new website, www.astronomy.org, the expedition was booked entirely within one week. * When the MC ended its involvement in 2007, my monetary contributions to the ASD Planetarium dropped by nearly 50 percent. The inside story was that I was being paid too much, but I had never received monetary compensation from the newspaper or AccessWeather. The fringe benefits from StarWatch proved more valuable. I stayed in education, doing what I loved. * By the time I joined the Moravian community in the spring of 2010, the weekly routine of writing, editing, and publishing StarWatch had become so ingrained within my schedule that it seemed natural to continue the column. Although StarWatch has a current subscription base of several hundred enthusiasts, down from 80,000 potential readers in its heyday, I still enjoy the process of hyping some of the key astronomical events during the year, telling stories about my teaching and astronomy experiences, and touting a little educational philosophy now and then. * How many more StarWatch articles will there be in the future? One thousand was my goal in 1996, but I have no reason to quit—my sincere thanks to my readers who continue to inflate my ego and my wife, Susan, who keeps me grounded. Don't hesitate to stay in touch or join. Email me and I'll add you to the mailing list. Ad Astra!

1501 MAY 25, 2025: Northern Lights: The Definitive Guide to Auroras: Northern Lights: The Definitive Guide to Auroras, written by Tom Kerss, HarperCollins Publishers, Dublin, 2021 (Amazon new, $15.95) is an excellent guide to understanding the history, causes, forecasting, chasing, and photography of the aurora borealis, the name that Galileo gave to a shimmering light display that he may have witnessed from northern Italy in 1607. I never considered that Galileo, Edmond Halley, Anders Celsius, and Anders Angstrom, among dozens of other less prominent scientists, influenced the advancement of auroral science long before the process was generally understood. For example, Angstrom was the first to isolate the spectral lines due to hydrogen in the sun. He also identified the wavelength of light that produced the lime green appearance of auroras seen predominantly at high latitudes. * The connection of the Earth-sun magnetic relationship in auroral activity is an underlying theme stressed throughout the book. If the movement or positioning of charged particles like electrons is regimented, a magnetic field results; however, strong magnetic fields cause charged particles to spiral around them and be carried away from the source that created them. This symbiotic relationship is the backbone for auroras. The sun and the Earth produce strong internal electrical currents, and their resultant magnetic fields play on one another. The problem is getting these particles to escape from the sun and then interact with the Earth's magnetosphere, the magnetic field surrounding our planet. * Enter solar flares, but more importantly, coronal mass ejections CMEs), which are often linked to each other. Magnetic field lines that normally loop energetic electrons and protons (plasma) back into the sun are suddenly broken, then reconnect, propelling vast amounts of plasma into space. The plasma, captured by the sun's magnetic field, pinwheel these charged particles outward into space, where they may eventually interact with Earth's magnetic environment. * Penetrating Earth's protective magnetosphere is tricky and not persuasively addressed in Kerss' Northern Lights, possibly because these mechanisms are still not fully understood. Once inside, however, the plasma rapidly migrates to Earth's intensely magnetic Van Allen Belts, where the electrons and protons race back and forth from magnetic pole to pole at relativistic speeds. This plasma eventually drops into Earth's ionosphere, where the electrons perform the lion's share of the work, causing primarily oxygen atoms to fluoresce (glow), creating the upper atmospheric reds and lower altitude greens that are so familiar to the observed colors of auroras. * Also addressed by Northern Lights are methods of predicting auroral events, including what latitudes can expect an active display. The local Kp (planetarische kennziffer) index, a numerical value between zero and nine, is created by compiling data from magnetometers in the US and Canada. They detect the direct flow of electrons from space into the ground and are probably the most reliable indicator of an auroral spectacle. Plasma speed, density, the interplanetary magnetic field strength, and the polarity of the incoming plasma also bear serious scrutiny. These factors contribute to creating a real-time forecast, but even this might not guarantee a display where you live. * I found Kerss' advice spot-on regarding traveling to specifically witness the northern lights. Stay focused, be patient, and be your own boss. Unless necessary, avoid group trips, which often have a carnival-type atmosphere created by less serious participants. Pete Detterline and I witnessed this on our last night in Iceland, and it was distracting, to say the least. Search for appropriate landscapes to enhance imagery, consider the lunar phase, and pray that the trifecta of Earth, sun, and weather will cooperate. * All in all, Northern Lights provides an excellent introduction to the auroral phenomenon and a primer for enthusiasts to enhance their odds of viewing one of nature's most awe-inspiring marvels. Ad Astra!