StarWatch: Moravian College Astronomy

APRIL 2020

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1233 APRIL 5, 2020: South Pole: Night on the Ice: Last week, I awoke not knowing if it was Wednesday or Thursday. After some “mental gymnastics,” I convinced myself that it was Wednesday, relaxed, and fell back to sleep. That could be the onset of early stage dementia, but then I have had it for the past 48 years, mainly occurring during the summer when regular routines become less important. The other aspect of my life that has changed since social distancing has become all the rage is bedtime. My students will tell you that hitting the sack at 2 a.m. is pretty normal for me because I usually return home from teaching around 11 p.m., and I need a few hours to decompress. However, for the last three nights it has been more like 4 a.m., and this morning it was 4:15 a.m. Don’t accuse me of TV binge watching either because at 3:45 a.m. I was updating a PowerPoint for my classes. These subtle changes in my life during the last three weeks are a mere shadow of what most people experience when they winter over at the Amundsen-Scott South Pole Station. Keep in mind that at the South Pole the sun sets several days after our vernal equinox because the seasons are reversed in the Southern Hemisphere. Why not on the vernal equinox, you might ask? That is because the much denser air at the frigid polar surface bends sunlight upwards causing Sol to be much higher in the sky than it actually is. Just because the sun has set doesn’t mean that it is gone forever. A few days later, it may pop above the horizon again, a flattened mangled representation of what it once was due to atmospheric refraction. Then there are about six weeks of growing darkness, an ever-dimming twilight circling around the horizon during each Earth spin. Eventually, the stars become visible, followed by complete darkness and unbearable cold. The last plane departs weeks before sundown. It’s eight or nine months before the next aircraft will thunder down the runway, signally the ending of winter isolation. The moon becomes the new sun, visible continuously for half a month, but “the most affecting memories for nearly every winter over are those of the dark days when the moon is down and the sky is as its most sublime.” Work crews perform their tasks on schedule; the scientists maintain their experiments, but some of the latter lose track of the “day and night” cycle. The keyword in the off hours is boredom. For many individuals, alcohol flows plentifully. Mark Bowen, author of The Telescope in the Ice, writes that the bar was a “…dark place on the second floor of the galley building, steeped in tradition, the beating heart of the station. About the only ways to escape from the boredom [aside from sex] were drinking and watching videos (1999 commentary).” For exercise some individuals walked or rowed the 850 miles to McMurdo Station on a treadmill or a rowing machine. Perhaps the strangest tradition at the South Pole is becoming a member of the 300 club. It has everything to do with the resilience of humans to endure pure agony. Participants first immerse themselves in a 200-degree F. sauna to get nice and toasty, then run buck naked (with boots on) to and from the geographic South Pole. This can only occur when the outside temperature dips below 100 degrees F. The roundtrip distance is about 500 yards. The aftermath of the condition of the partakers of the 300 club is a room that sounds like a TB clinic. So what’s my point here? Would you rather be stuck in the most socially isolated location on the planet in the frigid dark of the night or under house arrest in the beauty of springtime? It could be far worse, although I’ve got to admit, I’m running out of red wine. Governor Wolf, PLEASE HELP!

1234

APRIL 12, 2020: Ad Astra: Look to the Stars

In this time that challenges the national spirit, we need to remain strong. Our lives have changed as we are struggling to keep up with an uncertain landscape. For us today as we move towards the future, we look for ways to do honor to an Almighty Spirit, as well as to Nature as a place of wonder, support, and regeneration. Early humans were mesmerized by the luminescence of the night sky, the moon, the independence of the planets, and the tiny twinkling of a thousand points of light. That wonder which led us to understanding seems to be built into our DNA, even as we continue to quantify more and more of the universe around us. Still, marvel at the mysterious—dark matter and dark energy, composing 95 percent of the universe’s existence, secrets that must still be understood. If you wish to immerse yourself in the awe and wonder of the night sky, you might also realize that at the edge of our understanding is the panorama of trillions of unexplored worlds waiting for humanity’s discovery. Looking upwards imbues us with the serenity of the timeless stars; seeing the gossamer path of the Milky Way arching across the summer sky. We realize that we are citizens of the cosmos. For astronomy there always has been a contemplative aspect to gazing upward, a certain astonishment regarding the glory that anyone with sight can view on a moonless, clear night. Astronomy truly is the beautiful science. Times of great crisis beckon us to reach within ourselves for comfort and solace as well gaze upward towards the heavens. It strips away the false sense of having “unwavering control over our destiny.” It reduces us to living more in the moment, day by day, not insensitive to the conflicts raging around us, but more focused on the “now,” not the “what ifs” of the future. Irrational fears of the future ruin the present. We only have today, this moment—except when looking at the stars whose light we see tonight as having journeyed across the vast distances of time and space. You are witnessing their past, so far back in the case of galaxies, that their existence in the present may be uncertain and their futures still in the realm of the unexplained. Looking at the Deep and Ultra-Deep fields that the Hubble Space Telescope imaged many years ago have always been inspirational and regenerative. At first, you might think the fuzzy patches of starlight were the actual stars. Surprisingly, they were all galaxies, a photo of nothing but galaxies, composed of trillions of stars, and quite possibly quadrillions of planets, some that could possibly support sentient life. How wonderfully mind-blowing; how ecstatic a thought! Every society has a point where it can succeed brilliantly or not. Belief in the goodness in us, of our accomplishments, in our feats of triumph should make us want to aspire to continued greatness. How tragic it would be if humanity sidestepped its responsibilities after four billion years of evolution. As much as examples from astronomy were used, such illustrations can come from any of the sciences or the humanities. On Earth, the wedding of our collective accomplishments with the spiritual aspect of our being is a trait that perhaps only the human species possesses. Each day, new mysteries confront us, amaze and delight us, and challenge us to new heights of achievement. Find wonder, comfort, and regeneration in your own sphere of influence. We’re all in this together, and collectively with focus, determination, and perseverance we will succeed!

1235 APRIL 19, 2020: Snapple Bottle Caps: True or False?: Take an ice-cold glass bottle of Snapple and pop that cap. That was heaven for me when I taught in the Allentown School District. It was my afternoon treat and like the former Cracker Jack toys for kids, an additional pleasure was to read the factoid printed on the inside of the cap. I have Snapple caps scattered throughout the house, but I only keep the astronomy or geology ones that I have come across, so I wouldn’t consider myself a Snapple cap hoarder. I figured there had to be a website that listed all of them, and sure enough https://www.snapple.com/real-facts was the official site that did the trick. Here are some of them that deal with astronomy. Snapple away…
098: When the moon is directly overhead, you weigh slightly less. True, because you have two gravitational forces pulling in opposite directions. Something has to give, and your weight will lessen. Just don’t use this as a Weight Watchers’ trick to get extra points.
106: You would weigh less on the top of a mountain than at sea level. True… The Earth’s gravitational force of attraction which determines your weight decreases as the inverse square of the distance from the Earth’s center. At the summit of a mountain, you are farther away from the middle of the Earth and must weigh less. Here is a missed or future Snapple cap. A person weighs less at the equator than at Earth’s poles. Since the Earth rotates, it actually bulges at the equator and is flattened at its poles. The difference is nearly 26 miles between Earth’s polar diameter (7900 miles) and its equatorial diameter (7926 miles). Your best bet would be to find a tall mountain near the equator for an even greater micro weight loss. May I suggest Kilimanjaro in northeastern Tanzania at 19,340 feet or 20,548-foot Chimborazo in Ecuador. Because you are near the equator, you are also moving at a groundbreaking speed of 1040.4 miles per hour due to the Earth’s rotation. Can’t you feel your weight just flying off?
162: The temperature of the sun can reach up to 15 million degrees Fahrenheit. Untrue: The sun’s core temperature is about 26 million degrees F, 15 million Kelvin or 15 million degrees Celsius.
192: Jupiter spins so fast that there is a new sunrise every 10 hours. True, if you were close enough to the cloud tops so that the sun would be visible. A Jovian day equals 9 hours, 56 minutes.
206: Over one million Earths would fit inside the sun. True… A better estimate would be 1.3 million Earths which is more than one million Earths. I’ll give you that one, Snapple.
283: A compass needle does not point directly north. True… For most locations on the Earth, this answer is correct because the North Magnetic Pole is not in the same position as Earth’s Geographic North Pole, the point about which the Earth rotates. If you are in a location where the North Magnetic Pole is in the same line of sight as the Geographic North Pole, a compass works perfectly. Currently, the NMP is located on Ellesmere Island in northern Canada and is slowly moving towards Siberia. In the Lehigh Valley a compass needle points about 11 degrees to the west of true north. Scouts, beware! Follow the North Star (not the Drinking Gourd) which is a far better north indicator than a simple compass. At the North Pole a compass needle would point south, but then all directions at the North Pole point south.
I have got to stop here because my StarWatch articles have to fit into a box in their syndicated version. There are only 31 more caps left to discuss.

1236 APRIL 26, 2020: ATLAS Bombs, SWAN to Fly, Maybe: “Comets are like cats; they have tails, and they do precisely what they want.” I know I used that opening pickup line to introduce Comet Atlas (C/2019 Y4), to StarWatch readers just about one month ago. At that time ATLAS was exceeding brightness expectations, and astronomers were hoping that it would make a nice naked eye interloper gracing our mid-latitude evening skies during May. When first discovered on December 28, 2019 from atop Mauna Loa in Hawaii as part of the Asteroid Terrestrial-impact Last Alert System, Comet ATLAS was over a quarter million times fainter than the average human eye could detect. Calculations showed ATLAS’ orbit would approach the sun to 23.5 million miles, a very respectful distance for a showy event. Then ATLAS over performed, increasing its brightness by nearly 4000 times during March, which led some astronomers to expect a Great Comet. Others said nope; ATLAS was simply breaking apart, exposing more surface area to be disintegrated by the sun’s heat and ultraviolet radiation. I hate when the naysayers are correct, but since early April, photography revealed the coma, the densest area around the life-giving icy nucleus, to be elongating with bits and pieces of it crumbling off. ATLAS is not gone, but for naked eye and binocular observers, it may as well be forgotten. “That’s the way the comet crumbles,” read a Space.com headline. Even ATLAS is social distancing from Earth by simply breaking apart. When Bart’s Comet in a Simpson’s episode by the same title missed destroying Springfield, one of the residents of the town cried out, “Let’s go burn down the observatory so this will never happen again!” Luckily, the comet broke apart in the heavily polluted atmosphere above Springfield and hit the ground about the size of a Chihuahua’s head, an ad hoc prediction made by Homer to ease his family’s angst. So what happens now, lovers of the sky? Astronomers have yet another comet left in their collective hat. They believe it will become bright enough to be viewed with the unaided eye, a swan song to the ATLAS saga, and it just happens to be named SWAN (C/2020 F8), after the all-sky Solar Wind ANisotropies (SWAN) camera, mounted on the Solar and Heliospheric Observatory (SOHO). Discovered this past March 25 by Michael Mattiazzo of Australia, SWAN is coming at us from below the plane of the solar system. Its discovery by a satellite dedicated to making solar observations is far from unique. SOHO has found over 3500 comets to date, most of them kamikaze, vaporized by the sun’s intense heat. SWAN is currently visible in the southern hemisphere, but it is now rapidly moving northward. By the end of April, it should become visible as a binocular object in the predawn sky in the constellation of Aquarius. By mid-May (15-23) SWAN should (hopefully-perhaps-maybe) become a faint naked eye object, moving across the star pattern of Perseus, about 20 degrees off the NE horizon by dawn. At this point, I’m not holding my breath for any newly discovered comet, but if SWAN fizzles like ATLAS did, please don’t burn down my observatory. Email me instead, and I’ll direct you to a friend’s place.