thuban – welcome to somewhereville (.com)

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 September: Cassini's end and morning planet delights

The tail end of the August 21st eclipse from Nashville, including sunspot group 2671 at center and sunspot 2672, just clipped by the moon. (Photo by John Giroux)

Updated: Sep. 01, 2017, 3:07 p.m. | Published: Sep. 01, 2017, 2:07 p.m.

Special to nyup.com

By Damian Allis | Contributing writer

The Great American Eclipse for 2017 has come and gone without major reported inconvenience to the cities that ended up hosting large groups. This is good news for Western and Upstate New York, as we will be participants in the observation of totality on April 8, 2024 and have to contend with potential crowds on top of whatever weather early April brings that year. In the meantime, if you still have your eclipse glasses, you can give others an opportunity to enjoy upcoming total eclipses in South America and Asia in 2019. Consider donating your glasses to the great outreach organization Astronomers Without Borders – see the link for all the details.

The summer is set to give way to autumn on September 22nd, and some amateur astronomers have been counting down the minutes of daylight lost in favor of additional early observing time. September itself will be a busy month for both backyard astronomy and space science missions, with our closest planetary neighbors set to put on an elegant dance before sunrise all month just as one of NASA's great planetary missions ends its remarkably productive 20-year run on the morning of the 15th.

Lectures And Observing Opportunities In Upstate/Central New York

New York has a number of astronomers, astronomy clubs, and observatories that host public sessions throughout the year. Announced sessions from several respondent NY astronomy organizations are provided for September so you can plan accordingly. 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, as some groups will also schedule weather-alternate dates. Also use the contact info for directions and to check on any applicable event or parking fees.

Astronomy Events Calendar

Organizer	Location	Event	Date	Time	Contact Info
Adirondack Public Observatory	Tupper Lake	Public Observing	Sept. 1	7:00 – 10:30 PM	email, website
Albany Area Amateur Astronomers & Dudley Observatory	Schenectady	Senior Science Day	Sept. 4	3:00 – 4:00 PM	email, website
Albany Area Amateur Astronomers & Dudley Observatory	Schenectady	Night Sky Adventure	Sept. 19	7:00 – 8:30 PM	email, website
Albany Area Amateur Astronomers & Dudley Observatory	Schenectady	AAAA Meeting	Sept. 21	7:30 – 9:00 PM	email, website
Albany Area Amateur Astronomers & Dudley Observatory	Schenectady	Octagon Barn Star Party	Sept. 29	8:00 – 10:00 PM	email, website
Astronomy Section, Rochester Academy of Science	Rochester	Observing At The Strasenburgh	Sept. 2	9:00 – 10:30 PM	Jim S., 585-703-9876
Astronomy Section, Rochester Academy of Science	Rochester	Member Meeting	Sept. 8	7:30 – 9:30 PM	email, website
Astronomy Section, Rochester Academy of Science	Rochester	Observing At The Strasenburgh	Sept. 9	9:00 – 10:30 PM	Jim S., 585-703-9876
Astronomy Section, Rochester Academy of Science	Rochester	Farash Center Open House	Sept. 16	9:00 AM – 4:00 PM	email, website
Astronomy Section, Rochester Academy of Science	Rochester	Observing At The Strasenburgh	Sept. 16	9:00 – 10:30 PM	Jim S., 585-703-9876
Astronomy Section, Rochester Academy of Science	Rochester	Observing At The Strasenburgh	Sept. 23	9:00 – 10:30 PM	Jim S., 585-703-9876
Baltimore Woods	Marcellus	Goodbye Summer Skies	Sept. 15	7:30 – 9:30 PM	email, website
Kopernik Observatory & Science Center	Vestal	Friday Night Lecture & Observing	Sept. 1	7:00 – 9:00 PM	email, website
Kopernik Observatory & Science Center	Vestal	KAS Monthly Meeting	Sept. 6	7:00 – 9:00 PM	email, website
Kopernik Observatory & Science Center	Vestal	Friday Night Lecture & Observing	Sept. 8	7:00 – 9:00 PM	email, website
Kopernik Observatory & Science Center	Vestal	Friday Night Lecture & Observing	Sept. 15	7:00 – 9:00 PM	email, website
Kopernik Observatory & Science Center	Vestal	Friday Night Lecture & Observing	Sept. 22	7:00 – 9:00 PM	email, website
Kopernik Observatory & Science Center	Vestal	Friday Night Lecture & Observing	Sept. 29	7:00 – 9:00 PM	email, website
Kopernik Observatory & Science Center	Vestal	Moonlight Cafe Fundraiser	Sept. 30	7:00 – 9:00 PM	email, website
Mohawk Valley Astronomical Society	Waterville	Meeting	Sept. 13	7:30 – 9:00 PM	email, website
Mohawk Valley Astronomical Society	Waterville	Star Gazing	Sept. 23	8:00 – 11:00 PM	email, website
Mohawk Valley Astronomical Society	Waterville	Fall Fest Solar Observing	Sept. 30	12:00 – 3:00 PM	email, website
Mohawk Valley Astronomical Society	Waterville	Public Stargazing @ Waterville Library	Aug. 26/27	8:30 – 11:30 PM	email, website

Lunar Phases

Full Moon	Third Quarter:	New Moon	New:
Sept. 6, 3:02 AM	Sept. 13, 2:24 AM	Sept. 20, 1:29 AM	Sept. 27, 10:53 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 labeled image identifies features easily found with low-power binoculars.

Lunar features prominent in low-power binoculars.

Observing Guides

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 sky at 9 p.m. on Sept. 15, accurate all month except for the changing Moon position.

Evening Skies: The two most prominent shapes in the sky are the Big Dipper and the Summer Triangle, with the steam from the Sagittarius Teapot now engulfing the planet Saturn. The body of Scorpius, easily identified by the bright red-orange star Antares and now residing below Saturn in the nighttime sky, hooks down and back up around the southern tree line at our latitude in a shape that nearly every civilization has recorded as being a celestial scorpion. Like the Teapot, the Scorpion tail is between us and the galactic center – a scan with binoculars will reveal a number of objects that do not come into focus like their surrounding stars.

The Big Dipper is a bright and easy guide for finding Polaris, the north star. From its handle, you can "arc" down to bright star Arcturus, competing with Jupiter in brightness in this part of the sky. Jupiter, which stands out soon after sunset, is close to the bright star Spica in Virgo and to the southwest of bright Arcturus in Bootes. Saturn is also visible soon after dusk, rising soon after the bright orange star Antares in Scorpius.

The sky at 5 a.m. on Sept. 15, accurate all month except for the changing Moon position.

Morning Skies: Venus has left the crowded best-of-winter constellations and is heading towards Mars and Mercury in the pre-sunrise sky, passing through Cancer the Crab and into Leo the Lion. The bowtie shape that makes up the torso of Orion just cleared the horizon after 4:00 a.m. in early August and now rises before 1 a.m. at month's end. With the clearing of Canis Major about the horizon at month's end, the best-of-winter constellations will all be visible in the pre-dawn sky, providing a sneak preview of the nights to come.

Planetary Viewing

Mercury, Venus, and Mars:These three planets race ahead of the morning sun this month, offering us exceptional observing and imaging opportunities until close to month's end. Fleeting Mercury appears to race back towards the sun after September 20th, making the early month the prime time to see these three bright objects just under the mane and torso of Leo the Lion. The play-by-play of notable events is detailed below, with each event visible by 6:00 a.m. Binoculars will make each even more interesting, but be sure to put them away before sunrise:

Sept. 5: Mars will meet up with the bright star Regulus.

Sept. 10: Mercury will get its closest to Regulus.

Sept. 16: Mercury and Mars reach their closest, appearing as a binary star in binoculars.

Sept. 17: Mercury will begin rising after Mars.

Sept. 18: A sliver of a crescent moon is placed between Venus and the Mercury/Mars pair.

Sept. 23rd/24: Venus, Mars, and Mercury will be almost perfectly aligned and roughly equally spaced. If a meme about the biblical significance of the 23rd hits your social media feed, be ready to reply with the numbers 1827, 1483, 1293, and 1056.

Looking forward a bit, Venus and Mars will be at their closest on October 5th and excellent binocular targets from the 1st to the 9th next month.

The prominent planetary groupings in the morning sky this month.

Jupiter: Jupiter, low and to the southwest, is now competing with the bright, high-west star Arcturus for the title of brightest object in the neighborhood. Jupiter is setting earlier every night and will not be with us for easy observing by the end of September. If you don't catch it this month, you'll likely have to wait until December, at which point Jupiter becomes a bright morning object. You'll be able to find Jupiter quickly after sunset on the 21st and 22nd thanks to the moon, which will be at its direct right (21st) and then upper-left (22nd). Low power binoculars are excellent for spying the four bright Galilean moons – Io, Europa, Ganymede, and Callisto – and several online guides will even map their orbits for you.

Saturn: Still on the western edge of the brightest part of the Milky Way, Saturn is going to spend the next 16 months making its way to the eastern edge above the teapot of Sagittarius, all the while giving us an excellent observing target until next autumn. Those who have kept track of the double-double of Jupiter and Spica in the west and Antares and Saturn in the south will now have just this second southern double to contend with by month's end. Saturn will meet with the moon on the 26th, making for a hint of a question mark in the nighttime sky.

Not sure? It's Saturn and the Moon on Sept. 26.

Saturn will gain a little bit of weight this month, and news agencies will hopefully report the process in fine detail as we say goodbye to the Cassini Probe after 20 eventful years. The Cassini Mission, named for the Italian astronomer for whom the space between the largest rings – the Cassini Division – is named, ends in fiery form on the 15th when it hits the Saturnian atmosphere at about 70,000 mph. The reason for this dramatic, planned end is simple – NASA scientists do not want to risk an uncontrollable probe eventually reaching Titan or Enceladus, two of Saturn's moons that have enough of the key ingredients for life to possibly exist there. By crashing Cassini into Saturn, we guarantee that any potential lifeforms from Earth that might have survived on the probe itself do not have a chance to take root on one of the moons, meaning anything we might find later is truly native to the local environment and not, inadvertently, our fault.

A snapshot from the animated film "Cassini's Grand Finale."

ISS And Other Bright Satellites

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 month is divided into two ISS blocks. From the 4th to the 21st, observers will be treated to some very bright flyovers in the 4:30 a.m. to 6:15 a.m. range. From the 24th to the 29th, evening observers are treated to several exceptionally bright views. A number of less prominent flyovers are also predicted for the month and I encourage you to visit spotthestation.nasa.gov to see when some of these dimmer flyovers will occur.

ISS Flyovers

Date	Brightness	Approx. Start	Start Direct.	Approx. End	End Direct.
4-Sep	extremely	5:25 AM	SW	5:30 AM	E/NE
5-Sep	extremely	4:35 AM	SE	4:38 AM	E/NE
6-Sep	extremely	5:18 AM	W	5:22 AM	NE
7-Sep	extremely	4:28 AM	NE	4:30 AM	NE
7-Sep	very	6:01 AM	W/NW	6:06 AM	NE
8-Sep	very	5:10 AM	W/NW	5:14 AM	NE
9-Sep	very	4:20 AM	N/NE	4:22 AM	NE
16-Sep	extremely	6:14 AM	NW	6:20 AM	E/SE
17-Sep	very	5:22 AM	NW	5:28 AM	E
18-Sep	very	4:32 AM	N/NE	4:35 AM	E
18-Sep	extremely	6:06 AM	W/NW	6:12 AM	SE
19-Sep	extremely	5:15 AM	W/NW	5:20 AM	SE
20-Sep	very	5:59 AM	W	6:03 AM	S
21-Sep	very	5:09 AM	S/SE	5:11 AM	S/SE
24-Sep	very	8:44 PM	SW	8:46 PM	S/SW
25-Sep	very	7:52 PM	S/SW	7:56 PM	E/SE
26-Sep	extremely	8:35 PM	W/SW	8:39 PM	N
27-Sep	extremely	7:43 PM	SW	7:49 PM	E/NE
28-Sep	very	8:27 PM	W	8:31 PM	N/NE
29-Sep	extremely	7:34 PM	W/SW	7:41 PM	NE

Predictions courtesy of heavens-above.com. Times later in the month are subject to shifts – for accurate daily predictions, visit spotthestation.nasa.gov.

Learn A Constellation: Draco The Dragon

We return to our constellation survey with one of the original 48 constellations of antiquity. Sandwiched between the bowls of the Big Dipper and Little Dipper lies the long tail of Draco. This month, you might have an easier time remembering the brightest stars in this grouping by thinking not of a dragon, but instead of its distant cousin the snake – in the pre-midnight September skies, Draco looks like a backwards "S", with the Little Dipper half-surrounded by the bottom curve. Draco's head ends in a bright, four-starred asterism known as "The Lozenge," with its brightest star Eltanin making for a dim corner of a triangle with the Summer Triangle's Vega and Deneb.

Like dragons themselves, the stars of Draco once played a more significant role in human history and mythology than they do today. Due to the slow wobbling of Earth's rotation axis, the north star some 5,000 years ago was not Polaris in Ursa Minor, but instead Thuban, the third star of Draco's tail. In fact, the north-facing sides of the Egyptian pyramids were oriented to provide a view of Thuban – an example of how major astronomical phenomena may happen slowly on the timescales of individual people, but have already undergone notable changes in the still-short timeline of recorded history.

The curving shape itself is easy to follow if you start from the space between the bowls of the two dippers – Draco's tail stars are all the brightest stars along the curve. The head of Draco ends just east of the keystone of Hercules – a fitting location, as Draco also ended as one of Hercules' twelve labors. As you stare at the gap between the head and the tail curve in Draco, you're looking out into the densest part of what might be the largest known structure in the universe. The Hercules-Corona Borealis Great Wall is composed of billions of galaxies spread across what might be 10 billion light years – a structure so gravitationally massive that it must have formed very early in the history of the universe itself.

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.

Original Posts:

Tags:

astronomers without borders, cassini, cassini mission, cassini's grand finale, draco the dragon, great american eclipse 2017, john giroux, sunspot group 2671, sunspot group 2672, teapot, thuban

As first appeared in the May 2012 edition of the Syracuse Astronomical Society newsletter The Astronomical Chronicle.

Image generated with Starry Night Pro 6.

We return to our circumpolar constellation discussion begun with the Jan/Feb/March 2012 issue (our first "quarterly" report) by scaling up the Northern Horizon towards Draco the Dragon.

Draco, like all reptiles, is a bit on the dim side. Most of its constituent stars are in the 3 to 4.5 Magnitude range, making it an easy target in dark skies but a bit of a hunt near larger cities. If you've never looked for it before, it rivals Ursa Minor (the Little Dipper) in terms of "meh" apparent brightness in the sky (so it is far less pronounced than the Big Dipper or Cassiopeia, the two most prominent Constellations in this part of the sky).

Your best bet for identifying the stars in Draco may be to start right at the head and work your way down (and around, then over, then up, then way over the other way). One of my recent discoveries is that the head of Draco is, itself, a noted asterism (or noteworthy arrangement of stars that are not of the proper 88 Constellations) referred to as "The Lozenge" ("1" in the image above). I had been subconsciously thinking of Monty Python references to throw into this article and realized that saying "The Lozenge" several in a low John Cleese voice a la "The Larch" just about does it. The head of Draco is made from the brightest stars in the Constellation and does make for a reasonably easy target, as it sits between the two bright stars of the Little Dipper's bowl ("2" In the image at right) and Vega ("3"), the ridiculously bright star making its triumphant return to Spring skies (if you're at Darling Hill near sunset, you will see Vega as one of the first stars to appear above the Eastern Horizon well before it gets really dark). For those of you familiar with the Keystone (another famed asterism) that makes up the torso of Hercules ("4" in the image above), simply drive your eyes to the left-ish during the early night.

The historical origins of Draco as a lizard of any kind are localized to the Mediterranean, and these origins go back far enough that Draco is one of the Almagest's Original 48. The Greeks, and so the Romans, saw Draco as a Dragon (or, at least, lizard) of generally ill repute. Draco was seen by the Greeks as a guard of Hesperides' golden apples and/or a guard (or target, depending on how you read the sentence) of Jason's mythical golden fleece. The Romans saw Draco as the remains of the dragon killed by their goddess Minerva. It is perhaps fitting that, if you imagine Ursa Minor (the Little Dipper) as an ax on a questionably straight handle, then Draco is precariously on the celestial chopping block preparing to be cleft in twain.

The body of Draco is a healthy mix of single and double stars. In the boring single star category are Giausar, Thuban, and Nodus I. The double star list includes Edasich, Aldhibain, Altais, Rastaban ("eh mahn!"), Eltanin, and Grumium.

Thuban is one star in Draco to spend a bit of time on. In fact, it's one to spend several thousand years on. As late as 2700 B.C.E., Thuban held the place of Polaris as our North Star. The Earth may seem reasonably unchanging with respect to the seemingly unchanging arrangement of stars of our 100-year-ish lifetimes, but on the geological or cosmological timescales our Earth is as dynamic and fast-moving as that famed clay dreidel. The 26,000-year cycle we know as the precession of the equinoxes (shown above) is one of those processes that requires nearly the entire history of what we know as civilization to mark significant timespans for, but it is reported in several places that Thuban was of significance to the Egyptians in their building of the pyramids over 5 millennia ago (I would be happy to report that Thuban was the North Star that the main shaft of the great pyramid of Cheops was aligned to, but I've found conflicting reports online from otherwise reputable locations, so will simply report that the Egyptians very likely knew that this star appeared to move far less over the course of the night than any other and, therefore, held it with great regard).

For those observing at Darling Hill or anywhere south of Syracuse, Draco is a tough reptile to sustain one's astronomical appetite on. At least two comets are currently passing through Draco at the moment. One, LINEAR (C/2011 F1), is just off the Spindle Galaxy M102 (we'll come back to that) and, at 3 a.u. and closing, may improve beyond its apparent magnitude of 12.5. Draco also hosts Garradd (C/2008 P1) far beyond its tail star. At an apparent magnitude of 21.30, you have absolutely NO chance of seeing this comet from Darling Hill.

Draco is regrettably light on deep sky objects as well. The local color (at about 3400 light year) is provided by NGC 6543, known as the Cat's Eye Nebula (above). This is regarded as one of the most structurally complex nebulae in the Night Sky, although this complexity is only revealed through astrophotographic studies. NGC 5866 (below), also known as the Spindle Galaxy (which is very likely Messier 102, although some debate exists), is one of the great photographic sights in astronomy to my eyes. This edge-on galaxy view produces amazing density of material and spindly, fibrous clouds of dust and stars along the plane of the galaxy and a bright glow of stars all around this dense, dark line.

Now, the long curving body of Draco and its positions near the North Star does afford it one benefit in the Northern Horizon. Satellites! There are many bright (brighter than magnitude 4.0) satellites that follow paths over the Earth's poles, meaning those Constellations near the North and South poles are constantly getting pierced by manmade weather, communications, and "other" satellites. Simply letting my copy of Starry Night Pro go at high-speed with Draco at the center reveals over a dozen of these satellites over the course of just a few hours.