Upstate New York Stargazing – March, 2017

Author's Note: The "Upstate New York Stargazing" series ran on the newyorkupstate.com and syracuse.com websites (and limited use in-print) from 2016 to 2018. For the full list of articles, see the Upstate New York Stargazing page.

Upstate NY Stargazing In March: Messier Marathon and the Lunar Occultation of Aldebaran

M31, the Andromeda Galaxy, and its satellite galaxies M32 (a hazy star just above-left of M31's center) and M110 (the oval structure below-left of M31's center). Photograph taken at Kopernik Observatory & Science Center by Kopernik Astronomical Society member George Normandin. Click for a larger view.

Updated: Feb. 28, 2017, 5:12 p.m. | Published: Feb. 28, 2017, 4:12 p.m.

Special to nyup.com

By Damian Allis | Contributing writer

When someone refers to an astronomical object as "M" and a number, just what do they mean?

Once upon a time in astronomy, we didn't much know anything. Our classification throughout most of human history divided the nighttime sky into (1) pinpoints of light that didn't move with respect to each other (stars), (2) points of light that did move (planets), (3) random streaks of light that moved very quickly and disappeared (meteors), (4) the very rare pinpoints of light that grew bright and then disappeared completely (nova, supernova) and (5) the Moon.

There was also a rare sixth kind of object – comets. Comets grew bright over time before disappearing again, moved with respect to the backdrop of stars, looked like a hazy ball of light instead of a sharp pinpoint, and some were even known to come back around our way every certain number of years – a true hybrid of properties. Perhaps the most famous comet is the 75-ish year period Halley's Comet. Literary buffs will know that Mark Twain was born in 1835, the year of a Halley fly-by, and died in 1909, the year of the next Halley pass. He was even quoted as saying "It will be the greatest disappointment of my life if I don't go out with Halley's Comet."

European history buffs may know that the 1066 fly-by of Halley's Comet was seen as an omen – albeit an eventually poor one for Harold II of England, who suffered death and defeat at the swords and stirrups of William the Conqueror at the Battle of Hastings. The Bayeux Tapestry, which records the events leading up to this famed battle, even includes the sighting of the at-that-time-unnamed Halley's Comet.

Now we zoom in on the "M" – as it happens, many deep sky objects, including globular star clusters, galaxies, and nebulae, can look a bit comet-ish when magnified. This is especially true in poor quality equipment, where bad optics make everything unresolvable, adding a hazy glow to further confuse the issue. The "street cred" that came with the discovery of and naming rights for comets instigated many to push the limits of scope building and observing after Galileo's first foray into telescope observing, as better optics and higher magnification meant catching sight sooner than anyone else. Fortunately for methodical comet hunters, many of the hazy deep sky objects in their sights did not move in the sky with respect to the stars around them – meaning, to borrow from another space adventure, "these aren't the comets you're looking for."

Enter the "M" – Charles Messier, the famed French comet hunter whose observing prowess gave him a near-monopoly on comet discoveries between 1760 and 1785. In an effort to keep track of stationary stellar fuzz balls, and to pre-empt the erroneous reporting of new comets by others, Messier marked the locations of 17 comet-like objects in the sky that did not move, added 28 other fixed objects discovered previously, and published all 45 in 1774 in what became the first Messier Catalogue. The final catalogue published by Messier and his assistant Pierre Mechain in 1781 included 103 objects. The list was further expanded to 110 by later astronomers who saw evidence for the observations of M104 to M110 in M+M's observing logs, with M110 added just in 1967. The Messier Catalogue accounts for nearly all of the deep sky objects you can see with a decent pair of binoculars in the Northern Hemisphere.

For those keeping track, the irony of the whole situation is that Messier, famed comet hunter, is remembered for making a catalogue of those things which are, in fact, not comets.

All 110 Messier Objects – and most will not look this good in your binoculars Click for a larger view.

The entire Messier Catalogue, spread throughout the sky as it is, can be observed in its entirety under clear, dark skies very near the New Moon between mid-March and early April. Amateur astronomers the world over engage in what is known as the "Messier Marathon," one of the great yearly tests of an observer's equipment, eyesight, and patience. You have to start *very* soon after sunset to catch the earliest setters, then can enjoy a more leisurely tour of the nighttime sky, sneaking in an occasional nap or big cup of coffee before catching the last few objects *very* soon before sunrise. These marathons are not easy! Observers with several years of experience may have trouble seeing the dimmest members of the list, but even new observers with good binoculars and simple star charts can find the brightest members of the catalogue in what are often called "Messier Sprints." A web search for "Messier Marathon" will provide numerous useful links, including maps to these objects, recording logs for each object, and even the most efficient search order to find and record your observations.

March lectures and observing opportunities

New York has a number of evenly-spaced astronomers, astronomy clubs, and observatories that host public sessions throughout the year. Many of these sessions are close to the New Moon, when skies are darkest and the chances for seeing deep, distant objects are best. These observers and facilities are the very best places to see the month's best objects using some of the best equipment, all while having very knowledgeable observers at your side to answer questions and guide discussion. Many of these organizations also hold monthly meetings, where seasoned amateurs can learn about recent discoveries from guest lecturers, and brand new observers are encouraged to join and begin the path towards seasoned amateur status.

Announced public sessions from several respondent NY astronomy organizations are provided below for March. As wind and cloud cover are always factors when observing, please check the provided contact information and/or email the groups a day-or-so before an announced session. Also use the contact info for directions and to check on any applicable event or parking fees, Some groups will schedule weather-alternate dates for some sessions.

Astronomy Events Calendar

OrganizerLocationEventDateTimeContact Info
Adirondack Public ObservatoryTupper LakePublic Star GazingMar. 36:00 PMemail, website
Adirondack Public ObservatoryTupper LakePublic Star GazingMar. 176:00 PMemail, website
Albany Area Amateur Astronomers & Dudley ObservatorySchenectadySenior Science DayMar. 63:00 – 4:00 PMemail, website
Albany Area Amateur Astronomers & Dudley ObservatorySchenectadyAAAA MeetingsMar. 167:30 – 9:00 PMemail, website
Albany Area Amateur Astronomers & Dudley ObservatorySchenectadyNight Sky AdventureMar. 217:00 – 8:30 PMemail, website
Astronomy Section, Rochester Academy of ScienceRochesterASRAS Meeting And LectureMar. 37:30 – 9:30 PMemail, website
Astronomy Section, Rochester Academy of ScienceRochesterTelescope Tune-Up @ StrasenburghMar. 1811:00 AM – 4:00 PMemail, website
Baltimore WoodsMarcellusGoodbye To Winter SkiesMar. 37:00 – 9:00 PMemail, website
Baltimore WoodsMarcellusMercury, Jupiter, Spring SkiesMar. 316:00 – 9:00 PMemail, website
Kopernik Observatory & Science CenterVestalMonthly MeetingMar. 17:00 – 9:00 PMemail, website
Kopernik Observatory & Science CenterVestalFriday Night ObservingMar. 37:30 PMemail, website
Kopernik Observatory & Science CenterVestalFriday Night ObservingMar. 107:30 PMemail, website
Kopernik Observatory & Science CenterVestalFriday Night ObservingMar. 177:30 PMemail, website
Kopernik Observatory & Science CenterVestalFriday Night ObservingMar. 247:30 PMemail, website
Kopernik Observatory & Science CenterVestalFriday Night ObservingMar. 317:30 PMemail, website
Mohawk Valley Astronomical SocietyWatervilleLecture: Math And The UniverseMar. 87:30 PMemail, website

For those still smitten with the NASA discovery of seven Earth-sized planets around TRAPPIST-1, attendees in the Cazenovia area are invited to the free lecture "Distant Worlds: What We Know About Extra-Solar Planets And Their Potential For Habitability" on March 1st in Hubbard Hall at Cazenovia College, given by Dr. Leslie Hebb from Hobart and William Smith Colleges and co-sponsored by the Cazenovia College Science Cafe Committee and CNY Observers. For additional information, please send an email to lecture@cnyo.org.

Lunar Phases

New:First Quarter:Full:Third Quarter:New:
Feb. 26, 9:58 AMMar. 5, 6:32 AMMar. 12, 10:53 AMMar. 20, 11:58 AMMar. 27, 10:57 PM

The Moon's increasing brightness as Full Moon approaches washes out fainter stars, random meteors, and other celestial objects – this is bad for most observing, but excellent for new observers, as only the brightest stars (those that mark the major constellations) and planets remain visible for your easy identification. If you've never tried it, the Moon is a wonderful binocular object.

The grazing lunar occultation of Aldebaran. Click for a larger view.

Observers throughout Central and Southern New York are in for an observational treat on the evening of March 4th, when the Moon will occult the bright star Aldebaran, bright eye of the constellation Taurus the Bull. While the Moon occults, or blocks the light from, various stars and occasional planets all the time, the Aldebaran occultation is noteworthy because many observers will see Aldebaran just graze the Moon's edge. The luckiest observers may even see Aldebaran blink several times over the course of the occultation – this is huge! With no atmosphere to speak of, the blinking of Aldebaran you might see is, in fact, the star slipping behind large lunar geological features, such as high hills and the walls of impact craters. With enough observers and enough recorded data, astronomers can even make an elevation map of the grazed region of the Moon.

For those interested in all of the details, including the best ways to observe the event and how you can record data yourself for submission to the International Occultation Timing Association (IOTA), check out their official website.

Evening And Nighttime Guide

Items and events listed below assume you're outside and observing most anywhere in New York state. The longer you're outside and away from indoor or bright lights, the better your dark adaption will be. If you have to use your smartphone, find a red light app or piece of red acetate, else set your brightness as low as possible.

The view looking southwest at 9 p.m. on March 15 (except for the changing Moon position, this mid-month view is accurate for all of March). Click for a larger view.

Southern Sights: Orion, Taurus, and Canis Major are now primed for nighttime observing. High above them lies the twins Gemini – two very bright stars above Betelgeuse, the bright shoulder of Orion, will help orient you to find the stars that make up their bodies. These real beauties of winter skies will be nearly gone by the end of April, after which observers will have to wake up very early in August to see them again.

The view looking north at 9 p.m. on March 15. The Big Dipper is marked in green, including an arrow guide to finding Polaris, the North Star. Click for a larger view.

Northern Sights: Observers out during the late-evening hours are treated to a prominent Big Dipper standing upright in the northeastern sky and a prominent "E" shape in the northwest – the constellation Cassiopeia. The ancient king Cepheus sits near the horizon before midnight, looking like a dilapidated old barn. Once you've found the Big Dipper, take the two stars at the end of the bowl and guide your way to a moderately bright star surrounded by a mostly empty, dark piece of sky – this is the north star and tip of the Little Dipper handle, Polaris.

Planetary Viewing

Mercury starts the night above Venus on the 20th with Mars and a dim Uranus to the south. Click for a larger view.

Mercury: Mercury will be a bright pinpoint of light that will appear and then set just after sunset on March 11th. For the rest of the month, Mercury rises higher and sets later each night, falling behind Venus on the 20th and rising still higher in the sky through the end of March and early April. The 20th also offers a perfect time to catch four planets – Mars, Uranus, Mercury, and Venus – in the same part of the sky. On March 31, Mercury sets just after 9 p.m. EDT after crossing the Pisces-Aries border.

Venus on March 1st, off to the north of a tight grouping of the Moon, Mars, and Uranus. Click for a larger view.

Venus: Everyone's favorite misidentified UFO is going to zip along rather quickly from our view and through Pisces this month. Venus will set close to 8:30 p.m. on March 1st, a good 40 minutes or more before the crescent Moon and Mars do. On March 19th, Venus will set just after Mercury, newly arrived to the early-evening skies. On March 25th, Venus will set with the Sun and won't return to our evening skies until January of 2018. That said, Venus goes from being a bright evening object to a bright morning object instead! Between the 23rd and 25th, you have a decent chance of seeing Venus at sunset and at sunrise, after which Venus increasingly becomes a pre-dawn observing target until well into December of this year.

Mars: Mars will pair with the Moon this month in Pisces on March 1st and, once again, these two objects can guide you to finding the second-farthest planet in the Solar System. With luck and decent magnification, Uranus will appear as a green/blue point of light below Mars. If the Moon is too bright for easy scanning, simply wait until after the 1st for the Moon to make a little distance from Mars before trying for Uranus again. Mars will set very close to 9:20 p.m. EST / 10:20 EDT the entire month thanks to our mutual motions around the Sun, crossing the border from Pisces to Aries on March 8.

Jupiter and Moon close to Spica in Virgo on March 14. Click for a larger view.

Jupiter: March marks the triumphant return of Jupiter to our late-evening and early nighttime skies. On March 1, Jupiter rises in Virgo just after 9:30 p.m. By March 31, Jupiter will just hit the eastern tree line around 8:30 p.m. EDT.  Low power binoculars are excellent for spying the four bright Galilean moons – Io, Europa, Ganymede, and Callisto – and you are welcome to reproduce Galileo's observations of their motions around Jupiter. In fact, your generic, big-box store binoculars are a significant improvement over the equipment Galileo had at his disposal when he first began observing the heavens, so your task is all the easier. Several online guides will even map their orbits for you so you can identify their motions nightly or, for the patient observer, even hourly. The near-full Moon and Jupiter will make for a bright grouping with the bright Virgo star Spica in 10×50 binoculars after 10 p.m. EDT on March 14.

Saturn and the Moon on March 20th. Click for a larger view.

Saturn: Saturn continues it slow movement through Sagittarius this month, rising over the southeastern horizon just after 2:15 a.m. on March 1 and around 1:15 a.m. on the 31st. Saturn and the waning crescent Moon make for a close pair on March 20. Messier 23 will make for a small triangle in binoculars. The nebulae M21 and M20 can even be placed within the binocular field of view this night, but they will be very difficult to identify due to the brightness of the Moon.

ISS And Other Bright Flyovers

Satellite flyovers are commonplace, with several bright passes easily visible per hour in the nighttime sky, yet a thrill to new observers of all ages. Few flyovers compare in brightness or interest to the International Space Station. The flyovers of the football field-sized craft with its massive solar panel arrays can be predicted to within several seconds and take several minutes to complete.

The ISS is going to be an morning object until near the end of March. All of the morning sessions, from the 1st to the 23rd, fall into a window between 4:45 a.m. and 6:45 a.m., including double flyovers on the 18th, 20th, and 22nd. The "extremely" bright flyovers will be just that, with several expected to out-compete our late-evening Venus. At the end of the month, the ISS returns to the early evening, including double flyovers on the 29th and 31st. Simply go out a few minutes before the start time, orient yourself, and look for what will at first seem like a distant plane.

ISS fly-bys

DateBrightnessApprox. StartStart DirectionApprox. EndEnd Direction
3/1moderately6:05 AMS/SW6:11 AME/NE
3/3extremely5:56 AMSW6:03 AME/NE
3/4very5:05 AMS/SW5:10 AME/NE
3/5extremely5:48 AMW/SW5:54 AMNE
3/6extremely4:57 AMSW5:01 AME/NE
3/7very5:39 AMW5:45 AMNE
3/8extremely4:49 AMN/NW4:52 AMNE
3/9moderately5:31 AMW/NW5:36 AMNE
3/10moderately4:40 AMN/NW4:43 AMNE
3/11somewhat5:22 AMNW5:27 AMNE
3/12somewhat5:32 AMN5:34 AMNE
3/13somewhat6:13 AMNW6:18 AMNE
3/14somewhat5:23 AMN5:25 AMNE
3/15somewhat6:05 AMNW6:10 AME/NE
3/16somewhat5:14 AMN5:17 AMNE
3/17moderately5:56 AMNW6:01 AME
3/18extremely6:39 AMNW6:45 AME/SE
3/18somewhat5:05 AMN5:08 AME/NE
3/19very5:47 AMNW5:52 AME
3/20extremely6:30 AMW/NW6:36 AMSE
3/20moderately4:56 AMN/NE4:59 AME
3/21extremely5:39 AMNW5:43 AME/SE
3/22moderately6:21 AMW6:26 AMS
3/22moderately4:48 AME4:51 AME/SE
3/23extremely5:31 AMS/SW5:34 AMS/SE
3/26moderately9:05 PMS/SW9:07 PMS/SW
3/27very8:13 PMS8:17 PME
3/28extremely8:56 PMW/SW9:00 PMNE
3/29extremely8:03 PMSW8:09 PME/NE
3/29moderately9:40 PMW9:42 PMN/NW
3/30very8:46 PMW8:52 PMNE
3/31extremely7:53 PMW/SW8:00 PMNE
3/31somewhat9:31 PMW/NW9:34 PMN/NE

Predictions courtesy of heavens-above.com. Times later in the month are subject to change – for the most accurate weekly predictions, check spotthestation.nasa.gov.

Meteor Showers: No Major Showers This Month

As has been discussed in previous articles, meteor showers are the result of the Earth passing through the debris field of a comet or asteroid. While the orbits of scores of these objects bring them close to Earth's orbit, a limited number produce enough debris to produce significant meteor shower activity. February and March mark yearly lulls in major meteor shower activity, with the next prominent shower being the Lryids that occur in April. The astronomy community recognizes many minor showers that are predictable in their timing and are predictably unimpressive. Those interested in seeing a full list should check out the American Meteor Society meteor shower calendar.

Learn A Constellation: Ursa Major

Ursa Major and the Big Dipper, including brightest star labels, the locations of Messier Objects, and an arrow to follow to the north star Polaris. Click for a larger view.

For the first time in this series, we turn our constellation attention to the north. Standing to the northeast and nearly upright on its handle in the late evenings in March is the Big Dipper. In what might be the original instance of "let's take this argument outside," the Big Dipper and Orion have vied for the title of "most famous group of stars" among the amateur astronomy community for as long as people have needed reason to argue. Once pointed out, the Big Dipper is unforgettable, making it an ideal anchor to begin one's hobby as a lifelong star-hopper. As a place to spend the evening observing, the Big Dipper and its surroundings offer a great location to discover a number of interesting astronomical objects.

The Big Dipper, bright and famous as it is, is NOT a constellation. It exists as the torso and tail of the constellation Ursa Major, "The Great Bear." The Big Dipper is one of a handful of widely recognized groups of stars called "asterisms," which one can loosely define as "any group of stars that aren't defined as a constellation." It would be a Herculean task to propose any changes to the 88 modern constellations, but you are welcome to define any group of stars that jump out at you as an asterism – and authors have done so in astronomy books as aids to learning the locations of stars and other objects in the nighttime sky.

The ties that bind Ursa Major to the history of civilizations in the Northern Hemisphere are as much a wonder to behold as the stars themselves. The Romans recognized Ursa Major as a bear, it is one of the few groups of stars with Biblical citation, and tribes and civilizations throughout central and northern Europe up through Scandinavia recognized this star grouping as a bear. Closer to our home, the Iroquois, Algonquian, and Lakota also recognized Ursa Major as a bear early in their star lore. There are compelling arguments that this continental meta-drift is *not* just coincidence, but might be part of a shared oral tradition of nomadic peoples that goes back some 13,000 years to the early population of North America through Beringia, the Bering Strait Land Bridge that existed between Russia and Alaska during the last Ice Age. If true, this would place Ursa Major up there with Orion and Taurus as a *very* old star group.

Like the belt, shoulder, and knee stars of Orion, one can't help but see the trees from the forest by spying the Big Dipper before the dimmer stars of Ursa Major. The three handle stars, Alkaid, Mizar, and Alioth, connect at the dimmer star Megrez to the remaining bowl stars Dubhe, Merak, and Phecda.

Turning our attention to the middle of the handle, a fun game to play at public observing sessions is to ask "How many stars do you see at Mizar?" Those with good vision will see two – Mizar and its dimmer companion Alcor. The history of what follows is not set in stone, but is not really in dispute either – the observation of Mizar and Alcor was used by the Roman Army as an eye test for soldiers. Those who could see both had excellent vision and were candidates for lookouts. Following that logic, those who could only see Mizar were assured never to see a big battle from a safe distance. I suspect that those who couldn't see Mizar either were assured never to see a battle from behind those who could. Alcor and Mizar turn out to be much more complicated than just a simple pair – Mizar is, in fact, a double-double! Magnification reveals Mizar to be a bright pair of stars, while professional equipment reveals each of these stars to themselves be a pair of closely-spaced stars, all bound gravitationally. The dimmer Alcor is itself a binary, making for a combined grouping of six stars.

The seven Messier Objects within Ursa Major, including M40 (from NOAO/AURA/NSF), M82 and M81 (ESA/Hubble), M97 (dam Block/NOAO/AURA/NSF), M101 (ESA/NASA), M108 (Hunter Wilson), and M109 (Hunter Wilson). Click for a larger view.

Within the borders of this massive constellation reside seven Messier Objects. M40 is a double star that very clearly doesn't seem to be a fuzzy object. Its identification as a Messier Object has been labeled by some as "Messier's greatest mistake." M81 and M82 are a pair of gravitationally-interacting galaxies beyond the bowl and above the front shoulder of Ursa Major. M97, the Owl Nebula, is well within the field of view of Merak in binoculars – but you will need very dark skies and excellent dark adaptation to ever see this object. The Pinwheel Galaxy, M101, is just at the edge of 10×50 binoculars with Mizar placed at one edge of your field of view, but is bright enough for binoculars. Galaxies M108 and M109 round out the Messier list along the bottom of the bowl. Far from street lights and the Moon, these seven are all possible to see with good dark adaption, but patience and a reduced expectation of their visual quality is key. In all seven cases, you may find that your hands are not steady enough to easily see these wispy objects under magnification. Even for binocular viewing, I recommend a decent tripod and binocular tripod mount to improve your views.

Dr. Damian Allis is the director of CNY Observers and a NASA Solar System Ambassador. If you know of any other NY astronomy events or clubs to promote, please contact the author.

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Upstate New York Stargazing – December, 2016

Author's Note: The "Upstate New York Stargazing" series ran on the newyorkupstate.com and syracuse.com websites (and limited use in-print) from 2016 to 2018. For the full list of articles, see the Upstate New York Stargazing page.

Upstate NY Stargazing in December: Geminid meteor shower, another Supermoon

The author, adequately layered for an exceptionally cold observing session earlier this year.

Updated: Jan. 02, 2019, 4:15 p.m. | Published: Dec. 01, 2016, 11:15 a.m.

(Special to Syracuse.com)

By Damian Allis | Contributing writer

It is not common knowledge, but the late-autumn and winter holidays were strategically placed to allow amateur astronomers in New York to bulk up on high calorie foods for the many long nights of observing to be had before pre-dawn snow turns back into light drizzles. While advocates for some outdoor avocations go into hibernation mode near the first snow, celestial observers prepare for crisp and clear nighttime skies by stocking up on batteries and hand-warmers.

New and unprepared observers come face-to-frozen-face with the harsh reality of cold temperatures the first time they strike out for nighttime viewing in winter. Observing through binoculars or telescopes is a very stationery activity, where the goal is to move as little as possible to not disturb your view through the eyepiece. Your lack of motion has a tendency of making you feel very cold very quickly. Furthermore, when the temperature outside drops below that of your skin or your last good layer of clothing, you become the heat source for your surroundings and not vice versa – this can make for some very short observing sessions.

If you're thinking about attending any observing session in New York this winter, stop thinking and start planning. The winter skies are beautiful and filled with some amazing objects at any magnification provided you're dressed for the occasion. You need only be adequately prepared for the session, which means having on hand at least one more layer than you *think* you will need. Back in the day, many an observer would even have a telephone book ready to stand on to provide an additional layer of insulation between toes and ground. You may have trouble finding an adequately thick stack of cheap paper nowadays, but that first encounter with numb toes can coax you into some quality recycling bin search time.

Your First Steps Outside:

The view looking south at 8 p.m. on Dec. 15 (except for the changing Moon position, this mid-month view is accurate for all of December). Click for a larger view.

Items and events listed below assume you're outside and observing most anywhere in New York state. The longer you're outside and away from indoor or bright lights, the better your dark adaption will be. If you have to use your smartphone, find a red light app or piece of red acetate, else set your brightness as low as possible.

Mars: Mars continues its slow migration along the horizon from southwest to west this month, setting at around 9:00 p.m. each night in the process. Those keeping track of zodiacal constellations will note that Mars begins near the eastern-most corner of Capricorn before sliding into Aquarius on December 15th, trailed closely by bright Venus, which spends nearly the entire month in Capricorn. While Mars will not have close encounters with any deep sky objects this month, scope owners will be treated to very close pairing of Mars and Neptune on Dec. 31, as well as a close pairing to ring in the New Year on Jan. 1.

An ideal opportunity to find a distant planet using a nearby one. On Dec. 31, Mars and Neptune will be at their closest. To get a feel for how much the planets move each night, try observing on Jan. 1 to see Mars' new location. Click for a larger view.

Venus: We gain about two additional minutes of Venus viewing each night this month, setting close to 7:05 p.m. on the 1st and 8:20 p.m. on the 31st. After the Moon, Venus is the brightest object in the sky after sunset and should jump right out at you to the southwest. You'll have plenty of time to work on training your eyes to see first sight of Venus in the sky, as it remains with us near sunset until well into March 2017. Mars will hand off its close approach duties to Venus in January, when Venus and Neptune appear very close in the sky on Jan. 12.

Mercury, Venus, and Mars just after sunset on Dec. 15. Click for a larger view.

Mercury: Mercury will be a tough catch this month, as it is not particularly bright and is very close to the horizon at sunset. Your best chance to see it will be on Dec. 15, when it will be nearly perfectly southwest after sunset and all but gone before 6 p.m. That said, Mercury will be in roughly the same position and early-setting until around the 20th. If you can find Mercury, Venus and Mars will be much easier catches as you swing your sights higher and to the south.

Lunar occultation of Aldebaran on Dec. 12/13

If you go outside at, say, 9 p.m. over several consecutive nights and compare the position of the Moon to the stars and constellations in the sky, it will be obvious to you that the Moon makes a significant leap east each night. This is, of course, the motion of the Moon around the Earth that you are noticing. The Moon is, in fact, constantly in motion around the Earth, just as the Earth-Moon pair moves in our orbit around the Sun. The clearest indicator of this constant lunar motion comes from watching a star disappear behind the eastern side of the Moon, only to reappear on the western side up to 80 minutes later (depending on if the star is gazing the Moon's edge or if you have to wait a full Moon diameter's worth to see the star pop back out). Such an event, referred to as an occultation, is going to occur this month when the Moon occults the bright star Aldebaran, bright red-orange eye of the constellation Taurus the Bull.

Observers should see the occultation begin close to 11:09 p.m. on December 12th, lasting about 75 minutes when Aldebaran reappears on the western edge of the Moon at 12:23 a.m. on the 13th. These lunar occultations are common events – the Moon is always blocking some piece of the sky each night. This particular occultation is special because a very bright star is involved, making the whole disappearing-reappearing act all the more pronounced with or without magnification.

When an occultation involving a distant star and, for instance, a gas giant like Jupiter or Saturn occurs, we get more than a disappearing act. As the star begins to slip behind the planet, it does not disappear all at once, instead trailing off quickly behind the planet's upper atmosphere. By measuring the light of the star without the planet and then measuring the change in the star's light because of the planet, scientists and amateur astronomers alike are able to identify the gases in these planetary atmospheres from the comfort of their own telescopes and spectrometers. Keen observers this night will learn what the Apollo astronauts experienced firsthand – Aldebaran will fizzle out immediately due to the lack of any measurable lunar atmosphere.

Just before and after the lunar occultation of Aldebaran. Click for a larger view.

Early Riser Alert

Jupiter: Jupiter rises above the eastern horizon near 3:00 a.m. on December 1st and by 1:30 a.m. at month's end. Its four Galilean Moons – Callisto, Io, Europa, and Ganymede – are all visible in low-power binoculars when Jupiter rises, but are washed out early by sunlight even before sunrise approaches. Jupiter and the very waning crescent moon will make a very nice pairing after 2:00 a.m. on Dec. 22.

Saturn: Those who want one last easy view of Saturn in 2016 will have to wait until just before sunrise at the very end of December, when it rises just after Antares, the heart of the summer constellation Scorpius.

December observing opportunities In Upstate/Central New York:

New York has a number of evenly-spaced astronomers, astronomy clubs, and observatories that host sessions throughout the year. Many of these sessions are free and open to the public, often close to the New Moon when skies are darkest and the chance for seeing deep, distant objects is greatest. These observers and facilities are the very best places to see the month's best objects using some of the best equipment, all while having very knowledgable observers at your side to answer questions and guide discussion. Many of these organizations also hold monthly meetings, where seasoned amateurs can learn about recent news and discoveries from guest lecturers, and brand new observers are encouraged to join and begin the path towards seasoned amateur status.

Announced public sessions from several respondent NY astronomy organizations are provided below for December. As wind and cloud cover are always factors when observing, please check the website links or email the groups for directions and to find out about an event a day-or-so before the announced session. Also note that some groups will include weather-alternate dates for scheduled sessions.

Astronomy Events Calendar

OrganizerLocationEventDateTimeContact Info
Adirondack Public ObservatoryTupper LakePublic Star GazingDec. 26:00 PMemail, website
Adirondack Public ObservatoryTupper LakePublic Star GazingDec. 166:00 PMemail, website
Albany Area Amateur Astronomers & Dudley ObservatorySchenectadyPublic LectureDec. 157:30 – 9:00 PMemail, website
Albany Area Amateur Astronomers & Dudley ObservatorySchenectadyNight Sky AdventureDec. 207:00 – 8:30 PMemail, website
Baltimore WoodsMarcellusGeminids With Bob PiekielDec. 137:00 – 10:00 PMemail, website
Kopernik Observatory & Science CenterVestalNanomaterials Lecture And Public ViewingDec. 27:00 PMemail, website
Kopernik Observatory & Science CenterVestal"Star Of Bethlehem" Movie And Public ViewingDec. 97:00 PMemail, website
Kopernik Observatory & Science CenterVestal"Star Of Bethlehem" Movie And Public ViewingDec. 167:00 PMemail, website
Mohawk Valley Astronomical SocietyWatervillePublic Star GazingDec. 37:30 PM – 10:00 AMemail, website

ISS And Other Bright Flyovers:

Satellite flyovers are commonplace, with several bright passes per hour, yet a thrill to new observers of all ages. Few flyovers compare in brightness or interest to the International Space Station. The flyovers of the football-sized craft with its massive solar panel arrays can be predicted to within several seconds and take several minutes to complete.

December is full of early-evening ISS flyovers, including nine days when observers will be treated to two passes separated by about 90 minutes – the time it takes for the ISS to go once around the Earth. Early birds will have three chances to see flyovers during the last three days of the month. Simply go out a few minutes before the start time, orient yourself, and look for what will at first seem like a distant plane.

ISS fly-bys

DateBrightnessApprox. StartStart DirectionApprox. EndEnd Direction
12/1extremely5:51 PMS/SW5:55 PME
12/1somewhat7:28 PMW7:28 PMW
12/2very5:00 PMS5:05 PME
12/2very6:36 PMW/SW6:38 PMW/NW
12/3extremely5:44 PMSW5:49 PME/NE
12/3somewhat7:21 PMW/NW7:21 PMW/NW
12/4very6:29 PMW6:31 PMN/NW
12/5extremely5:36 PMW5:42 PMNE
12/5somewhat7:14 PMNW7:14 PMNW
12/6moderately6:22 PMW/NW6:24 PMN/NW
12/7very5:29 PMW5:34 PMNE
12/8moderately6:15 PMNW6:17 PMN
12/9very5:22 PMW/NW5:27 PMNE
12/9somewhat7:00 PMNW7:00 PMNW
12/10moderately6:08 PMNW6:10 PMN
12/11moderately5:15 PMNW5:20 PMNE
12/11somewhat6:52 PMNW6:53 PMNW
12/12very6:00 PMNW6:03 PMN/NE
12/13very5:08 PMNW5:13 PMNE
12/13moderately6:44 PMNW6:45 PMNW
12/14very5:52 PMNW5:56 PMNE
12/15very5:00 PMNW5:06 PME/NE
12/15very6:36 PMW/NW6:39 PMNW
12/16extremely5:44 PMNW5:49 PME
12/16somewhat7:21 PMW7:22 PMW
12/17very6:29 PMW/NW6:33 PMS
12/18extremely5:37 PMW/NW5:43 PMSE
12/19somewhat6:22 PMW6:26 PMS
12/20moderately5:29 PMW/NW5:35 PMS/SE
12/22somewhat5:22 PMW5:26 PMS/SW
      
12/29moderately6:25 AMS6:30 AME
12/30somewhat5:34 AMS/SE5:36 AME/SE
12/31very6:16 AMSW6:22 AME/NE

Predictions courtesy of heavens-above.com.

Moon: Lunar Phases

New:First Quarter:Full:Third Quarter:New:
Nov. 29, 7:18 AMDec. 7, 4:03 AMDec. 13, 7:05 PMDec. 20, 8:55 PMDec. 29, 1:53 AM

The moon's increasing brightness as full moon approaches washes out fainter stars, random meteors, and other celestial objects – this is bad for most observing, but excellent for new observers, as only the brightest stars (those that mark the major constellations) and planets remain visible for your easy identification. If you've never tried it, the moon is a wonderful binocular object.

In the interest of completeness, we note that the last supermoon of 2016 will occur on December 14th. The term "supermoon" is not an astronomical description of any significant event, but instead owes its origin to modern astrologer Richard Nolle (and don't get an astronomer started with that debate). For those interested in technical jargon, astronomers refer to these closest approaches of the Moon to the Earth as perigee-syzygy. Perigee describes when the Moon is closest to the Earth in its orbit; Syzygy occurs when the Sun, Earth, and Moon are aligned, which happens at either New Moon (Sun-Moon-Earth) or Full Moon (Sun-Earth-Moon). For those counting double-letter/double-word scores, syzygy also only occurs when someone combines the tiles from two or more Scrabble boxes.

Sadly, the December supermoon has only one superpower – it will wash out the shooting stars from the Geminids, greatly diminishing this otherwise decent meteor shower.

Meteor Showers: Geminids, Peaking Dec. 12-14

Meteor showers are the result of the Earth passing through the debris field of a comet or asteroid. As these objects approach the warming sun in their long orbits, they leave tiny bits behind – imagine pebbles popping out the back of a large gravel truck on an increasingly bumpy road. In the case of meteor showers, the brilliant streaks you see are due to particles no larger than grains of sand. The Earth plows through the swarm of these tiny particles at up-to 12 miles-per-second. High in the upper atmosphere, these particles burn up due to friction and ionize the air around them, producing the long light trails we see. We can predict the peak observing nights for a meteor shower because we know when and where in Earth's orbit we'll pass through the same part of the Solar System – this yearly periodicity in meteor activity is what let us identity and name meteor showers well before we ever had evidence of what caused them.

Gemini rises soon after Orion, with Orion's three belt stars being a very easy find for most people. Click for a larger view.

The name of each meteor shower is based on the constellation from which the shooting stars appear to radiate – a position in the sky we call the radiant. In the case of the Geminids, the meteor shower radiant appears to be next to Castor, both the name of one of the twins and the name of his head star. Unlike most of the meteor showers, the Geminids are not produced by a comet – asteroid 3200 Phaethon, an unassuming object not discovered until 1983, has an eccentric 1.4 year orbit that places it near the path of Earth's orbit. Because of its proximity and quick orbit, 3200 Phaethon has great opportunity to repopulate its orbit with small particulates, meaning the Geminids are often a stand-out meteor shower for the year.

The eccentric orbit of 3200 Phaethon in the inner solar system.

How to observe: The Geminids can be impressive and impressively bright, with up-to 120 meteors per hour possible. Sadly, the Moon will be prominent in the late-night/early-morning sky during the days around the Geminid peak, making for a far less impressive display. Those observing the Aldebaran occultation on the night of December 12th might even be able to catch a few of the brightest meteors that night.

To optimize your experience, lie flat on the ground with your feet pointed towards Gemini and your head elevated – meteors will then appear to fly right over and around you. Counts and brightness tend to increase the later you stay out, with peak observing times usually between 1 a.m. and 5 a.m. The swarm of tiny particles is distributed broadly in orbit, meaning some people may see shooting stars associated with the Geminids throughout the middle of the month.

Learn A Constellation: Taurus The Bull

Taurus the Bull and nearest neighbors. Click for a larger view.

Once upon a time in our distant ancestral past, someone broke an excellent spear tip trying to take down a jagged rock that just happened to look like dinner under the fading light of sunset. More recently, it's a fair bet that everyone has looked up at the clouds or into just the right thicket of bushes to see some kind of animal-like feature jump out. This phenomenon, known as pareidolia, is the result of some kind of stimulus, be it a sound or a sight, that you then interpret as something very different.

Many of the oldest constellations are textbook pareidolia. The stars of Orion the Hunter are perfectly placed now to look like a human being, just as the constellation Scorpius has been recorded as a scorpion in every civilization that knew what a real scorpion looked like. These and other characters have been with Western cultures for thousands of years.

This all leads to a great question in astronomy and human history – just how old is the oldest recognized constellation? At what point in our history could we travel back to and have a distant ancestor and ourselves agree on what a shape in the sky looks like?

One answer was uncovered in the Lascaux caves in France, when an archeologist with some astronomical inkling noticed that one image of a bull had black spots at strategic points along the horns and around the head, including one notably larger black spot for one of the two eyes. To the right of this cluster of marks lay a tightly-packed cluster of black dots, while to the left lay a line of three (actually, four) stars. If we take this arrangement at rock-face value, the placement of the three-dot line to the left and tight cluster to the right line up very well with the placement of Orion's Belt (to the left) and the Pleiades star cluster (to the right) on either side of the head of what we today call Taurus the Bull. If this arrangement and overlaid image of a bull are what the original artist intended, and we take the carbon dating at face value, then we've compelling evidence that Taurus the Bull, in some form, might date back over 17,500 years.

No bull – a Lascaux painting marking the location of an ancient Taurus, c.a. 15,500 B.C. Click for a larger view.

While it is wondrous to think that this celestial meme was passed down by ancestral astronomers throughout southern Europe into the Middle East and North Africa, it is likely that the meaning of the representation at Lascaux died with its painter, and our modern Taurus is instead a result of someone else seeing the same shape on a winter night long ago.

Taurus is featured several times in this month's article, including its close proximity to Gemini and, of course, the Aldebaran occultation on December 12th. In last month's article, we described how Taurus contains the two closest prominent open star clusters in our neighborhood – the Pleiades and the Hyades. The head of Taurus the Bull is the closest star cluster to Earth – the Hyades. While the bright Aldebaran is perfectly placed to make the whole object look like a prominent "V," this is only because we see the sky as flat. Aldebaran, at 65 light years away, is not a member of the Hyades cluster, which lies roughly 150 light years from us.

The Pleiades are the most famous of these open clusters due to their proximity – in binoculars, the famed Seven Sisters increase in number to the mid-30's. The actual count of stars in this collective is measured as being close to 1000. On cloudy nights, observers need only find their nearest parking lot to see a rough map of the Pleiades in the form of a logo – in Japanese, the Pleiades are known as "Subaru," meaning "united."

Dr. Damian Allis is the director of CNY Observers and a NASA Solar System Ambassador. If you know of any other NY astronomy events or clubs to promote, please contact the author.

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