StarWatch: Moravian College Astronomy

OCTOBER 2022

OCTOBER STAR MAP | MOON PHASE CALENDAR | STARWATCH INDEX | NIGHT SKY NOTEBOOK

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

Current Solar X-rays:

Current Geomagnetic Field:

lunar phases

1363 October 2, 2022: "Weather" to Visit Cherry Springs: It is a fact that Cherry Springs State Park located about 10 miles to the southeast of Coudersport, PA offers some of the darkest skies available to East Coast astronomers. It is well worth the trip even if you are just going to lay out in a sleeping bag for a few hours and watch the sky visually or through binoculars. However, the downside to Cherry Springs is that it is located in the cloud belt, a region extending from central Pennsylvania up through central New York which is prone to greater amounts of overcast and inclement weather conditions. * This region is affected by weather systems moving south from Canada across the Great Lakes, eastward across the continental US, and low-pressure systems riding up along the Atlantic Seaboard. It is a good bet to pay attention to the National Weather Service forecasts so that a wonderful dark sky experience does not turn bleak because of grey skies. However, you cannot plan ahead based upon the predictions of the seven-day forecast, especially for a place like Cherry Springs. Accuracy at this distance is only about 10 percent. At three days out, the forecast generally has a 50 percent correctness. Confidences of 90 percent are normally achieved 24 hours before the event. To minimize disappointment, plans should always be fluid and adaptable when contemplating a visit to Pennsylvania's dark sky site. * There are several National Weather Service products that I use and that may be helpful to StarWatch readers to help to plan whether an astronomical event is a Go/No Go situation. The first is the National Weather Service graphical forecast which looks at the weather over the period of one week divided into day and night segments. If you click on the above link, you will see a map of Pennsylvania. Cherry Springs is to the southwest of Elmira by about 60 miles. I always move down the column to Sky Cover, the amount of cloudiness that is over a location. Once that link is activated, different times of the week and night can also be accessed. If the cloud cover is greater than 37.5 percent, partly cloudy, don't go. Clear represents, up to 12.5 percent cloud cover, while mostly clear can have up to 37.5 percent of the sky obscured by clouds. I would also check the seven-day forecast for Coudersport which can be accessed here. The first five days are presented as visual images with textual forecasts below. Two partly cloudy nights sandwiched between a mostly clear or clear night would be "a go," but not two mostly cloudy nights with a partly cloudy night in between. * Finally, there is another wonderful NWS product which lets you see the cloud cover in real time over the area you want to visit. Click here to access the National Center for Atmospheric Research. Near the bottom left of the page, you'll see loop duration. I normally input two hours. Then click on BWI (Baltimore-Washington International) to see the movement of clouds over the mid-Atlantic states. With these three products you'll be armed and forewarned of any nasty weather that might impact Cherry Springs or your own backyard. Go here to see my weather page on astronomy.org. Ad Astra!

1364

October 9, 2022: One Year to Major US Eclipse

By this time StarWatch readers should know how enthusiastic I am about viewing solar and lunar eclipses, even eclipses seen on other planets as my students witnessed the other week when the shadow of Ganymede was cast onto the cloud decks of Jupiter. Solar eclipses are special, not only because of the rapidly changing lighting effects which are spectacular to view, but because they are rare and involve very precise alignments of the sun, moon, and Earth. * Just one year from now on October 14, 2023 the moon's shadow will bathe the entire continental US, most of Canada, all of Mexico and Central America, and most of South America. However, in the US along a narrow strip of land starting in southwestern Oregon, northern Nevada, south central Utah, diagonally across New Mexico, and near the Mexican border across western and southeastern Texas, enthusiasts will witness a ring of fire as the smaller moon is completely silhouetted against a slightly larger sun. * Of the two types of central solar eclipses, annular eclipses are less spectacular than total solar eclipses, simply because part of the sun remains visible at all times, denying observers the stunning, rapid darkening effects of totality. Still in all, they are a must-see event for the serious observers of nature as long as onlookers protect their eyes with filters or use projection devices to view the event. * This will be my fourth annual eclipse, having witnessed others in 1984 (Osceola, North Carolina), 1994 (Canutillo, Texas), and 2012 (Chaco Canyon National Historical Park, near Nageezi, New Mexico). Ironically by coincidence, the 2023 annular eclipse path again bullseyes itself across Chaco Culture where I hope to be stationed. At Chaco, the moon will be ringed by the sun for a duration of 4 minutes, 42 seconds. The central path of annularity also overtakes Oregon's Crater Lake National Park, Winnemucca, Nevada; Torrey, Utah; Albuquerque, New Mexico; Odessa and Corpus Christi, Texas; among many other locations before heading southeastward across the Gulf of Mexico, down along the eastern backbone of Central America, before entering Columbia and ending at sunset off the easternmost coastline of Brazil. * The Lehigh Valley will witness a partial solar eclipse beginning at 12:05 p.m. with the sun almost 40 degrees above the horizon. Maximum eclipse occurs at 1:20 p.m. with the sun nearly 41 degrees in altitude and about 25 percent of the solar disk obscured by the moon. The partial eclipse will end at 2:36 p.m. with the sun at an altitude of 34 degrees. Good eclipse hunting to everyone. Ad Astra!

It is time to get ready to see this eclipse.

Based on 20 years of weather data, the above map shows the likelihood of cloud cover on October 14, 2023. Darker gray areas represent higher chances of cloud cover. The orange lines show the path of the October 14, 2023, annular eclipse. Weather map courtesy of Time and Date

1365 October 16, 2022: October Skies: With the first frost on the pumpkin only days away and the sun's light continuing to wane, the sky is also reflecting our deepening rendezvous with winter. To the north, the Great Bear (Big Dipper) that dominated the spring and summer heavens is now beginning to walk along the horizon looking for a place to hibernate. She will be nearly invisible during the early evening hours until February when Callisto will once again begin her yearly climb into the spring heavens. Cassiopeia, Queen of Ethiopia, and Perseus the Hero, have now taken her place as the dominant fall constellations in the northern firmament. * Approaching the zenith in the south are the constellations of Pegasus the Flying Horse and Andromeda the Maiden, daughter of Cassiopeia, who was rescued by Perseus from the terrifying jaws of Cetus the Whale. Cetus can also be found in the October sky. Just beyond the zenith in the western heavens is a mid-summer leftover, the Great Summer Triangle composed of the bright stars, Deneb (faintest), Altair, and Vega (brightest). * Within these two groups, Pegasus and Andromeda and the Great Summer Triangle are a galaxy and two double stars that are easy to observe with just binoculars. I'll start with the Andromeda Galaxy, but first look at the all-sky map set for this week at 9 p.m. and the enlargement of the two green sectors which can be accessed here. * At 9 p.m. you'll find the body of Pegasus high in the southeast. It is composed of four stars which form a baseball diamond and are known as the Great Square. From the upper left of the square, three stars seem to form a back leg, but that is really the star pattern of Andromeda who is holding onto the horse as Pegasus transports her back to Perseus' country where shortly they will overthrow the evil king, Polydectes, to become the new rulers. The second star in Andromeda, distant from the corner of the Great Square of Pegasus, is labeled "One" in the inset. That is where you should begin viewing. You'll be able to follow the trail of stars, "Two" and "Three," which will lead you to the galaxy. Once you've found star "Three," the Andromeda Galaxy will appear as a small fuzzy football-shaped object nearby. You'll be seeing photons of light that have traveled 2.4 million years (light years) just to enter your eye. * The two other objects are double stars. Epsilon Lyrae is the easier of the pair to view. Simply find Vega, the brightest luminary of the Great Summer Triangle. If you are facing south, then move your binoculars slightly to the left, and you'll see two stars that are very close to each other and about the same brightness. You have found Epsilon Lyrae. Keep in mind that each of those stars is also a double, but to split those components, you will need a good telescope and a magnification of about 100 power. Albireo represents the head of Cygnus the Swan, but from suburbia Cygnus appears very much like a cross. If your hands are steady, Albireo which is positioned at the foot of the cross and can be split with binoculars. Here the two stars are quite different in brightness. * Referring to the large map, do not forget to check out Jupiter, Saturn and lonely Fomalhaut, the alpha star of Piscis Austrinus the Southern Fish, an obscure constellation best seen from the Southern Hemisphere. Its location is discernable in the Northern Hemisphere only because of bright Fomalhaut. At the present time, the three objects form an equilateral triangle visible in the south. If you go out later, let's say at 11 p.m., keep in mind that everything will have shifted to the west, but you will also be able to view ruddy Mars in the east as well as the gossamer star cluster called the Pleiades, which is also best seen with binoculars. Enjoy the night. Ad Astra!

1366 October 23, 2022: Asterisms of Autumn: One of my favorite questions that students almost always crash and burn when answering involves the seven stars of the Big Dipper. The query is "What constellation is this?" The answer that pops from their lips is, of course, the BD. I usually make some harsh type of buzzer sound to indicate the answer is incorrect, and the surprise among my students is really perceptible, proving the pervasiveness of this really popular misconception. The correct answer is Ursa Major the Great Bear. What they are confusing is the difference between an official constellation and an asterism. * A constellation has been sanctioned by the International Astronomical Union, the World Congress of Astronomers, while an asterism represents the specific cultural or national identity of a group of stars. To Americans these seven luminaries are readily recognized as the Big Dipper. Travel to Germany and these same seven stars represent the Wagon or Wheelbarrow; Czech Republic, Big Wagon; England, the plow; Holland, the Steel Pan; Saudi Arabia, the Kite and so on. * Asterisms abound in the night sky of autumn. The four luminaries that form the cup of the Big Dipper, now beginning to slide along the northern horizon after dark, is an asterism in itself called the Bier. It represents the platform on which the casket was carried in a traditional funeral procession long ago. * The Little Dipper which represents the same stars as the constellation of the Little Bear, Ursa Minor, is also an asterism as well as the second and third brightest luminaries of the star pattern found in the cup, Beta and Gamma Ursa Minoris. As the Earth rotates, they circle around the North Celestial Pole which is close to the North Star, also called Polaris, and are known as the Guardians of the Pole. * The "W" or "M" which represents a good deal of the chair that evil Cassiopeia, Queen of Ethiopia, sits upon as she is carried around the heavens is also an asterism as is the Great Square of Pegasus, the body of the Flying Horse. The "W" is currently in the NE after sundown while the Great Square is high in the south looking like a baseball diamond. Low in the east by 10 p.m. will be a "V-shaped" asterism with a bright, orangey star, the head of the constellation of Taurus the Bull. You are looking at the Hyades, a very old star cluster that is 625 plus million years old, minus orangey Aldebaran which is not a member. Don't get Aldebaran confused with even brighter, ruddy Mars to Aldebaran's left. Use binoculars to view the "V" more easily. Over the next several hundred million years, its members will slowly evaporate, moving away from the cluster to assume their own, lonely orbits around the Milky Way Galaxy. * Above Aldebaran is positioned my favorite asterism, the Pleiades, a much younger, 100-million-year-old star cluster which appears like a small hazy exhalation on a cold winter's day. From suburbia, four to six stars are visible to the unaided eye within its misty surroundings. This cluster like the Hyades can also be best seen with binoculars. With the unaided eye the Pleiades may be spotted before the Hyades, since it is considerably higher in the sky by 10 p.m. * Finally, I cannot omit the Great Summer Triangle which is visible high in the western sky. The faintest of the three luminaries that compose it is Deneb, the alpha star of Cygnus the Swan, a constellation that from suburbia looks more like a cross and is appropriately called the Northern Cross, another asterism. By December it will stand on the northwestern horizon, a beautiful reminder of the Season of Light. There are many more asterisms in the fall sky that can be seen here. Ad Astra!

1367 October 30, 2022: The Astronomy Surrounding Halloween: Many years ago, I had the pleasure of eavesdropping on a conversation between two of my Allen students. One was trying to persuade the other to visit a haunted house in New Jersey, near Philadelphia, where 20 dollars offered an individual access to 20 "floors" of horror. According to the conversation, each level that a person survived netted the participant a dollar in return, but according to the persuader, no one had ever made it past the eighteenth floor. It was male teenage bantering at its best. * Contemplating death is certainly my greatest fear, and I suspect for most others, even though the Internet seems to dwell upon spiders. Yet each year at the very end of October, many of us revel in Halloween, a sort of "nose thumbing" to our successful efforts in eluding the Grim Reaper for still another year. All Hallows' Eve, October 31, has its roots steeped in astronomy, just like Groundhog Day, February 2, May Day, May 1, and the festival of the first fruits, Lammas, August 1. They fall on or close to what are known as cross-quarter days, the midpoints between the four major seasonal markers of the sun: the winter solstice (low sun), the vernal and autumnal equinoxes (mid-sun positions), and the summer solstice (high sun). * If you think about it, the cross-quarter day of October 31 is an excellent time to celebrate our vanquishing of death for yet another year. The comfortable period of summer's warmth and abundant light has passed. Our focus upon darkness and the cold of an encroaching winter season overwhelms our spirits as the sun treks lower each day in our noontime sky, rising later each morning and setting earlier each evening. * Leave it to the pastoral Celts to have envisioned the harvest festival, Samhain (sa-win), meaning summer's end, and the Gaels (also Celts) of present-day Ireland and southwestern Scotland to add a touch of the macabre to this celebration. They believed that the veil separating the worlds of the living and the dead thinned on All Hallows' Eve, permitting the creatures of the netherworld—the souls of the dead, ghosts, fairies, and demons to move freely about in the world of the living. * Sacrifices of animals and plants were made to pacify the deceased, and bonfires were lit to help to guide these ghouls along their paths and keep the departed separated from the living. Offerings of food and drink were left outdoors to appease and persuade these creatures from entering the homes of the living. Later, people dressed in costumes to scare away the roaming dead, performed tricks and antics on others to receive a treat, ushering in our more modern ritual of "trick or treating." * The response of the Catholic Church to these popular frolics was to establish the more serious All Saints' Day on November 1 and All Souls' Day on the 2nd; but in the end, Christianity was unsuccessful in ending the dark traditions surrounding Halloween, the night of the living dead. Happy All Hallows' Eve to all who celebrate! A Halloween photo illustration can be found below. Ad Astra!