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Upstate New York Stargazing – June, 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.

June Stargazing in Upstate NY: What to look for in the night skies this month

Different as night and day, except for their apparent size. The partial solar eclipse on 21 February 2012 from the Solar Dynamics Observatory. *(NASA/SDO/AIA)*

Updated: Jun. 01, 2017, 12:07 p.m. | Published: Jun. 01, 2017, 11:07 a.m.

Special to nyup.com

By Damian Allis | Contributing writer

For solar eclipse enthusiasts, the next 600 million years are a great time to be alive.

Solar eclipses from Earth are stunning due to the magic of geometry. The Sun's diameter is about 400 times that of the Moon – meaning you could line up about 400 Moons, or 107 Earths, from solar pole-to-pole. That said, the Sun is also about 400 times farther away from the Earth than the Moon is. To the observer on the ground, the Sun and Moon then appear to take up the same exact amount of celestial real estate. This is easy to test for yourself with the help of some solar eye protection – both the Moon and the Sun are about 1/2 the width of your pinky when your arm is fully extended.

This has not always been the case! Among all of the scientific data handed to astronomers by the Apollo Missions, two stand out. First, the rocks they brought back for analysis ended up being remarkably similar in composition to those you might find on the Earth's surface. This and a wealth of other data helped establish the current model for how the Earth-Moon system formed – a violent collision of a Mars-sized object with the early Earth kicked up enough of early Earth's surface to form the Moon.

Second, astronauts on the Apollo 11, 14, and 15 missions placed reflectors on the lunar surface in order to measure the Earth-Moon distance with, literally, laser accuracy. What we know from nearly 50 years of the Lunar Laser Ranging Experiment is that the Moon is slipping away from Earth at a rate of 3.8 cm per year. The available scientific data tells us that the Moon, when it first formed, was much closer to the Earth than it is now – and it has been moving away ever since.

When the Moon was much closer, the Sun would have disappeared behind it and taken some time to go from one edge of the Moon to the other in the process. Such events in astronomy are called occultations, and most commonly occur now when the Moon passes between ourselves and a star or planet. As our Moon moves much farther out, it will only cover a fraction of the Sun's surface – a phenomenon we call a transit. It is very roughly estimated that that last perfect total eclipse from the Earth's surface will occur in less than 600 millions years – if work or cloud cover keep you from the August 21st eclipse this year, there's still time to catch a few others.

For more information on the Aug. 21 eclipse, check out this NASA website.

Lectures and things to see

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 below for June. 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	Eclipse Lecture	June 2	7:00 – 9:00 PM	email, website
Albany Area Amateur Astronomers & Dudley Observatory	Schenectady	Senior Science Day	June 5	3:00 – 4:00 PM	email, website
Albany Area Amateur Astronomers & Dudley Observatory	Schenectady	AAAA Meetings	June 15	7:30 – 9:00 PM	email, website
Albany Area Amateur Astronomers & Dudley Observatory	Schenectady	Octagon Barn Star Party & Lecture	June 16	8:00 – 10:00 PM	email, website
Albany Area Amateur Astronomers & Dudley Observatory	Schenectady	Night Sky Adventure	June 20	8:00 – 9:30 PM	email, website
Albany Area Amateur Astronomers & Dudley Observatory	Schenectady	National Asteroid Day	June 30	9:00 – 10:00 AM	email, website
Astronomy Section, Rochester Academy of Science	Rochester	ASRAS Meeting & Lecture	June 2	7:30 – 9:30 PM	email, website
Astronomy Section, Rochester Academy of Science	Rochester	Observing At The Strasenburgh	June 3	8:30 – 10:30 PM	Jim S., 585-703-9876
Astronomy Section, Rochester Academy of Science	Rochester	Observing At The Strasenburgh	June 10	8:30 – 10:30 PM	Jim S., 585-703-9876
Astronomy Section, Rochester Academy of Science	Rochester	Observing At The Strasenburgh	June 17	8:30 – 10:30 PM	Jim S., 585-703-9876
Astronomy Section, Rochester Academy of Science	Rochester	Observing At The Strasenburgh	June 24	8:30 – 10:30 PM	Jim S., 585-703-9876
Baltimore Woods	Marcellus	Spring Constellations	June 16	9:00 – 11:00 PM	email, website
Kopernik Observatory & Science Center	Vestal	KAS Monthly Meeting	June 7	7:00 – 9:00 PM	email, website
Kopernik Observatory & Science Center	Vestal	Friday Night Lecture & Observing	June 2	8:00 PM	email, website
Kopernik Observatory & Science Center	Vestal	Friday Night Lecture & Observing	June 9	8:00 PM	email, website
Kopernik Observatory & Science Center	Vestal	Friday Night Lecture & Observing	June 16	8:00 PM	email, website
Kopernik Observatory & Science Center	Vestal	Friday Night Lecture & Observing	June 23	8:00 PM	email, website
Kopernik Observatory & Science Center	Vestal	Friday Night Lecture & Observing	June 30	8:00 PM	email, website
Mohawk Valley Astronomical Society	Waterville	Public Stargazing @ Waterville Library	June 17	9:00 PM	email, website

Lunar Phases

New:	First Quarter:	Full:	Third Quarter:	New:	First Quarter:
May 25, 3:44 PM	Jun. 1, 8:42 AM	Jun. 9, 9:09 AM	Jun. 17, 7:32 AM	Jun 23., 10:30 PM	Jun. 30, 8:51 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.

Evening and nighttime guide

The view looking south-southwest at 10 p.m. on June 15 (except for the changing Moon position, this mid-month view is accurate for all of June).

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.

Southern Sights: The two gas giants of the Solar System – Jupiter and Saturn – are at prime locations for observing in binoculars this month. Exceptionally bright Jupiter is perfectly placed to help you find Spica to the West, Regulus and Leo the Lion to the east, Arcturus to the North, and the small constellation Corvus to the South. Saturn rises after the bright red-orange star Antares in Scorpius – one of our early markers for the edge of the bright band of the Milky Way and the wealth of intra-galactic Messier Objects.

The view looking northeast at 10:00 p.m. on June 15th.

Northern Sights: The Big Dipper is high in the northern sky during pre-midnight observing hours this month. Those prone to stiff necks can take in the brightest objects in the Summer Triangle now while it is low on the eastern horizon. If your search for M13 in Hercules becomes a strain, consider starting your summer stretching exercises soon.

Planetary viewing

Mercury: The fleet-footed Mercury will be a tough catch even in the first week of June, after which it rises close enough to sunrise to be washed out by sunlight. You should not attempt to observe it in binoculars unless you have a steady hand or a good tripod – magnified sunlight, even in low-power binoculars, can instantly AND permanently damage your eyes. Mercury will return to sunset skies in July, then become a morning target again in August.

Venus: Venus remains an unmissable morning observing target in Aries, rising after 3:30 a.m. on the 1st and by 3:00 a.m. on the 30th. It does continue to slip away from us visually, but we see more of its illuminated surface in the process. The result is an only slight dimming of the planet over the entire month as it goes from 40% to 60% illumination.

Venus has two closes approaches with the Moon on June 20th and 21st.

Mars: You hopefully had your fill of Mars these past few months. June marks the end of our easy Mars viewing, as it's low enough on the horizon to be nearly washed out by sunlight. Consider a binocular scan low along the horizon for a final glimpse before 9:00 p.m. this month, but ONLY do so AFTER sunset to protect your vision.

Jupiter: As of the writing of this article, the first presentation of data back from the Juno Mission has just changed some of our understanding of the planet Jupiter in fundamental ways, and astronomers eagerly await new data and theories to explain these recent observations. In the meantime, the basics haven't changed since Galileo first followed the four brightest moon – give Jupiter a good look in a telescope or binoculars to see what he saw.

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 so you can identify their motions nightly or, for the patient observer, even hourly.

Jupiter and the Moon on June 3rd and June 30th in Virgo.

Saturn: We remain in countdown mode for the end of the Cassini Mission by way of a very rapid decent into Saturn's upper atmosphere on September 15th. Saturn rises just after 9:30 p.m. at the beginning of the month and by 7:30 p.m. at month's end, making it an excellent nighttime target throughout. Still on the western edge of the brightest part of the Milky Way, Saturn is going to spend the next 18 months making its way to the eastern edge, all the while giving us an excellent observing target from late Spring to mid-Autumn.

While markedly closer to us, Saturn is not the brightest object in this part of the sky. Your eyes may be drawn to the orange star Antares in Scorpius first – simply look to the east for another bright pinpoint. Saturn and the Moon have a close approach inside the borders of Ophiuchus on June 10th.

Saturn and the Moon on June 10th, with Antares bright and to the west.

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 an excellent late-night target for the first 12 days of June, after which it will disappear from our nighttime skies completely until early July. You even have two chances to catch it three times in a single day – although you'll have to start just after midnight on the 1st and 4th and wait patiently until that evening to see all three flyovers. 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 Flyovers

Date	Brightness	Approx. Start	Start Direction	Approx. End	End Direction
1-Jun	very	12:03 AM	NW	12:06 AM	N/NE
1-Jun	somewhat	9:34 PM	NW	9:39 PM	NE
1-Jun	moderately	11:11 PM	NW	11:16 PM	E/NE
2-Jun	moderately	12:48 AM	W/NW	12:48 AM	W/NW
2-Jun	moderately	10:19 PM	NW	10:24 PM	E/NE
3-Jun	moderately	9:27 PM	NW	9:32 PM	NE
3-Jun	very	11:03 PM	NW	11:08 PM	E/NE
4-Jun	somewhat	12:40 AM	W/NW	12:40 AM	W/NW
4-Jun	very	10:11 PM	NW	10:17 PM	E
4-Jun	very	11:48 PM	W/NW	11:50 PM	W/NW
5-Jun	moderately	9:19 PM	NW	9:24 PM	E/NE
5-Jun	extremely	10:55 PM	NW	10:59 PM	E
6-Jun	very	10:03 PM	NW	10:09 PM	E
6-Jun	moderately	11:40 PM	W/NW	11:42 PM	W
7-Jun	extremely	10:48 PM	W/NW	10:51 PM	S/SW
8-Jun	extremely	9:55 PM	W/NW	10:01 PM	E/SE
8-Jun	somewhat	11:33 PM	W/SW	11:33 PM	W/SW
9-Jun	very	10:40 PM	W	10:43 PM	S/SW
10-Jun	very	9:47 PM	W/NW	9:53 PM	S/SE
12-Jun	moderately	9:40 PM	W	9:45 PM	S

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

Meteor Showers: June Bootids, active June 26 to July 2, peaking June 28

Meteor showers occur when the Earth passes 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 usually 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 identify and name meteor showers well before we ever knew what caused them.

The June Bootids are generally not even worth mentioning as a meteor shower to stay awake for, with only one or perhaps two associated meteors expected per hour. On rare occasions, however, persistent observers are treated to quite a show, including a notable outburst in 1916 and one in 1998 that produced 100 bright streaks per hour at peak.

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. The June Bootids appear to radiate from the very tip of the kite – the modern object that Bootes the Herdsman most resembles. One object Bootes will not be keeping much watch over is the first-quarter moon, which will set early enough to not impact your viewing of this, very-likely, unimpressive shower. The end of the handle of the Big Dipper is also an easy marker for this shower.

How to observe: To optimize your experience, lie flat on the ground with your feet pointed to the northwest and your head elevated – meteors will then appear to fly right over and around you.

Those interested in seeing a full list should check out the American Meteor Society meteor shower calendar.

Learn a constellation: Cepheus

Cepheus, a broken barn hovering over the throne of Cassiopeia this month.

King Cepheus – Cassiopeia's husband, Andromeda's father, and eventual father-in-law to Perseus – is arguably less prominent both in terms of mythology and amateur astronomy than the other three. A greater appreciation comes from filling in the details – just as there may be a more interesting backstory to the king, the stars and few known celestial objects within the boundaries of the constellation Cepheus are made much more interesting when you know more about what you're looking at.

During pre-midnight hours in June, Cassiopeia appears as a large "W" just east of due north. Cepheus, which looks more like a dilapidated barn than any other object, can be found by looking straight up above the "W" – the roof will be pointing west.

Within the barn lie some of the largest stars yet discovered. The variable star RW Cephei lies just at the border between Cepheus and Lacerta and would, if sent to replace our Sun, extend out towards the orbit of Saturn. It varies in brightness but, even at its dimmest, is still a reasonable binocular object. VV Cephei is another monster star that is circled by an observable binary companion. Mu Cephei is reason enough to go buy a pair of binoculars. Commonly known as Herschel's "Garnet Star," and less commonly known as Erakis (not to be confused with Arrakis of Dune lore, although it does have the sand-like color to it), Mu Cephei is perhaps the most strongly colored star you can see with or without magnification.

A final notable star is Delta Cephei, the star that gave us the term "cepheid variable." The star varies in brightness every 5 days and 9 hours – you can even reproduce the observations of John Goodricke in 1784 by doing your own comparison of its brightness against the backdrop of neighboring stars. There turns out to be a relationship between the brightness of a cepheid variable and the time it takes to go from minimum to maximum brightness – a discovery made by Harvard "computer" and pioneering female astronomer Henrietta Swan Leavitt. This early study eventually provided a way of using cepheid variables as cosmic measuring sticks to, among other things, determine distances in the Milky Way, determine distances to galaxies in our Local Group, and even help establish the Hubble Constant – the rate at which the universe appears to be expanding.

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:

arcturus, cassini mission, cepheus, galilean moons, hubble constant, john goodricke, juno mission, king cepheus, lunar laser ranging experiment, m13, messier objects, solar eclipse

Upstate New York Stargazing – May, 2017

Upstate NY Stargazing in May: A meteor shower and preparations for the solar eclipse

The transit of Venus across the Sun on June 5/6, 2012. By NASA/SDO, AIA.

Updated: May. 01, 2017, 12:00 p.m. | Published: May. 01, 2017, 11:00 a.m.

Special to nyup.com

By Damian Allis | Contributing writer

Every once in a while, New York and most of the rest of the U.S. is treated to some significant daytime astronomical phenomenon. As you might imagine, this only occurs when some object attempts to compete with the Sun for attention – and this only occurs when something big gets between the Sun and ourselves.

Within the past decade, we've had the good fortune of being able to see Venus (in 2012) and Mercury (in 2016) transit, or travel across the face of, the Sun using solar-safe astronomy equipment. The 2012 Venus transit held in downtown Syracuse even drew several hundred people to Armory Square.

On Aug. 21, the continental U.S. is going to be witness to a total solar eclipse – an event that hasn't happened for us since 1979. While New York will not experience complete coverage of the Sun, northern-most New Yorkers will experience about 70 percent coverage, while southern-most New Yorkers will just barely approach 80 percent. It is a fair bet that every active astronomy club in New York will be hosting an observing session with solar-safe equipment on the 21st or will be hosting a lecture of some kind in the days leading up to the eclipse.

If you haven't yet done so, mark Aug. 21 in your calendar and plan to call in sick that afternoon. We will address solar-safe observing and why such eclipses don't happen more regularly as the event approaches. For those already excited and looking for more information, check out eclipse.gsfc.nasa.gov/eclipse.html, greatamericaneclipse.com, or eclipse2017.org.

May lectures and observing opportunities

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 below for May. 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 Star Gazing	May 5	8:30 PM	email, website
Adirondack Public Observatory	Tupper Lake	Public Star Gazing	May 19	8:30 PM	email, website
Albany Area Amateur Astronomers & Dudley Observatory	Schenectady	Senior Science Day	May 1	3:00 – 4:00 PM	email, website
Albany Area Amateur Astronomers & Dudley Observatory	Schenectady	Night Sky Adventure	May 16	8:00 – 9:30 PM	email, website
Albany Area Amateur Astronomers & Dudley Observatory	Schenectady	AAAA Meetings	May 18	7:30 – 9:00 PM	email, website
Albany Area Amateur Astronomers & Dudley Observatory	Schenectady	Octagon Barn Star Party & Lecture	May 19	8:00 – 10:00 PM	email, website
Astronomy Section, Rochester Academy of Science	Rochester	ASRAS Meeting & Lecture	May 5	7:30 – 9:30 PM	email, website
Astronomy Section, Rochester Academy of Science	Rochester	Observing At The Strasenburgh	May 6	8:30 PM	Jim S., 585-703-9876
Astronomy Section, Rochester Academy of Science	Rochester	Observing At The Strasenburgh	May 13	8:30 PM	Jim S., 585-703-9876
Astronomy Section, Rochester Academy of Science	Rochester	Observing At The Strasenburgh	May 20	8:30 PM	Jim S., 585-703-9876
Astronomy Section, Rochester Academy of Science	Rochester	Observing At The Strasenburgh	May 27	8:30 PM	Jim S., 585-703-9876
Baltimore Woods	Marcellus	Spring Constellations	May 19	8:30 – 10:30 PM	email, website
Kopernik Observatory & Science Center	Vestal	KAS Monthly Meeting	May 3	7:00 – 9:00 PM	email, website
Kopernik Observatory & Science Center	Vestal	Friday Night Lecture & Observing	May 5	7:00 – 10:00 PM	email, website
Kopernik Observatory & Science Center	Vestal	Friday Night Lecture & Observing	May 12	8:00 – 10:00 PM	email, website
Kopernik Observatory & Science Center	Vestal	Friday Night Lecture & Observing	May 19	8:00 – 10:00 PM	email, website
Kopernik Observatory & Science Center	Vestal	Friday Night Lecture & Observing	May 26	8:00 – 10:00 PM	email, website
Mohawk Valley Astronomical Society	Waterville	Public Stargazing @ New Hartford Sherrill Brook Park	May 20	9:00 PM – 12:00 AM	email, website

Lunar Phases

New:	First Quarter:	Full:	Third Quarter:	New:
Apr. 26, 8:16 AM	May 2, 10:46 PM	May 10, 5:42 PM	May 18, 8:32 PM	May 25, 3:44 PM

Evening and nighttime guide

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

Southern Sights: May is the last month to catch an easy glimpse of Orion and Taurus, but the bright stars in Auriga and Gemini help to fill in your observing time. The thin, wispy band of the Milky Way in this part of the sky runs thickest through the feet of Gemini and all of Monoceros. As you look further east, you're looking off the plane of our galaxy into the deep void of intergalactic space.

This means you see fewer Messier Objects inside the galaxy, but Virgo specifically is a prime location for hunting many galaxies that would otherwise be covered over by even the thinnest band of the Milky Way.

The view looking northeast at 9:00 p.m. on May 15.

Northern Sights: The Big Dipper lies high in the sky during pre-midnight observing hours this month.

Arcturus and Hercules are easy targets by the time you're ready to observe, and bright Vega in the constellation Lyra now clears the tree line, marking one corner of the Summer Triangle and the wealth of deep sky objects starting their return within the densest region of the Milky Way.

Planetary Viewing

Mercury swapped places with Venus briefly at the beginning of April as the first planet to fall below the horizon after sunset. For May, Mercury has followed Venus to the morning sky, giving early risers a great chance to catch multiple planets before sunrise later in the month. For the first two weeks, Mercury will rise close to civil twilight and be virtually washed out by sunlight. Looking due east for a very bright pinpoint in binoculars may seal the deal, but be VERY careful about keeping your view away from the rising sun. The damage to your eyesight from even a second of the magnified sun is instant and permanent.

True to its name, Mercury will fly through the constellations Pisces, Cetus, and Aries this month. The early morning of May 23rd will host the thin, waning crescent moon between Mercury and the exceptionally bright Venus. The distant planet Uranus will even share the lunar field of view in 10×50 binoculars that morning, but likely be too difficult to see against the brightness of even the sliver of a crescent.

Mercury, Venus, a thin crescent Moon, and even possibly Uranus on the morning of May 23.

Venus is unmissable in the morning sky right now, rising after 4:30 a.m. on May 1 and by 3:45 a.m. on the 31st. Its thin crescent shape is very visible even in low-power binoculars, but you may need something to steady your hands if you're going to try to see this crescent clearly.

If you don't have a camera tripod and binocular bracket handy, a common cheap trick is to flip a broom over and steady the binos on the bristles – but vacuum them off first!

Fortunately, you've the whole month to practice – Venus will be slipping farther away all month within the Pisces border, but its crescent will grow from a quarter to nearly one-half by month's end, giving us plenty of reflected light to monitor the process in May and beyond.

Mars remains a reasonable, but dimming, catch in the western sky after sunset and will be visible within the borders of Taurus before 10:00 p.m. all month. That said, June will mark the transition from Mars to not-Mars in the evening sky, after which we'll be waiting until the early mornings in mid-August for another sight.

The Mars and Moon, looking west on May 27.

Jupiter is in its viewing prime in May, rising near 6:00 p.m. on the 1st and by 4:30 p.m. on the 31st. Throughout the month, it will be high and visible in the pre-midnight sky, never straying too far from the star Porrima in the constellation Virgo. On the evening of May 7th, the waxing gibbous Moon will be at its closest to Jupiter, making for an excellent pairing in binoculars. At that point, Jupiter will be easy to spot – and possibly the only other object in the vicinity of the Moon that you can see.

Saturn Saturn has seen some excellent press in the past few weeks and you will hopefully be seeing quite a bit more of it in the few months to come. The Cassini Mission, which has done as much for scientific study as it has for desktop backgrounds since beginning its study of Saturn in 2004, is ending in a most spectacular way on September 15th of this year, when the satellite is scheduled to fall into Saturn itself. The reasons are two-fold. First, the probe will have exhausted its plutonium fuel supply. Second, and more importantly down the road, there's always a slight chance that Cassini has been hiding microbial hitchhikers from Earth all this time. An uncontrolled probe might just end up crash-landing into one of Saturn's moons, such as Titan or Enceladus, in which case there's a slight chance that those hiding microbes might just set up shop and begin populating a life-less moon – or possibly start competing with any native microbes that astrobiologists are anxiously hoping to find during future missions.

Saturn returns to the pre-midnight sky on May 1st, rising earlier each night until clearing the horizon just before 10:00 p.m. on the 31st. Saturn sits right near the Sagittarius/Ophiuchus border this month, crossing into Ophiuchus territory on May 20th. May 13th will see the waning gibbous Moon paired with Saturn, rising just before midnight. This is an excellent sight in binoculars, but not necessarily the best Saturn sight this month. If you're a true night owl, try to find Saturn after 2:00 a.m. during the first few mornings in May – so long as the Moon has set below the western sky, you may be able to spy Saturn, the open star clusters Messier 21 and 23, as well as the Trifid and Lagoon Nebulae – all in the field of view of 10×50 binoculars. This is when a tripod, good chair, and a good long look in the binoculars will serve you best. If the 2 a.m. session isn't your thing, simply wait until after May 22, when the Moon is below the horizon and Saturn et al. rise after 11 p.m.

An exceptionally busy view of Saturn in binoculars.

ISS And Other Bright Flyovers

May is chock full of ISS, with 72 nighttime-visible flyovers predicted. The first few weeks of May offer a great number of these flyovers, but only if you're willing to start your day off very early. The flyovers for the first few weeks all occur after 2 a.m., but only three occur on or after the late hour of 5 a.m. The flyovers for pre-midnight observers begin after the 22nd, with three chances per day to observe the ISS on the 24th, 26th, 28th, 30th, 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 Flyovers

Date	Brightness	Approx. Start	Start Direction	Approx. End	End Direction
6-May	very	4:54 AM	S/SW	5:00 AM	E/NE
8-May	extremely	4:47 AM	SW	4:52 AM	E/NE
10-May	extremely	4:39 AM	W	4:44 AM	NE
12-May	very	4:31 AM	W	4:36 AM	NE
20-May	somewhat	12:51 AM	NE	12:51 AM	NE
22-May	moderately	12:41 AM	N/NE	12:43 AM	NE
22-May	moderately	11:49 PM	N/NE	11:51 PM	NE
23-May	very	9:17 PM	S	9:21 PM	E
23-May	extremely	10:52 PM	W/SW	10:58 PM	NE
24-May	moderately	12:29 AM	W/NW	12:34 AM	NE
24-May	extremely	9:59 PM	SW	10:06 PM	E/NE
24-May	moderately	11:36 PM	W/NW	11:42 PM	NE
25-May	extremely	9:07 PM	S/SW	9:13 PM	E/NE
25-May	very	10:44 PM	W	10:50 PM	NE
26-May	moderately	12:21 AM	NW	12:26 AM	NE
26-May	extremely	9:51 PM	W/SW	9:57 PM	NE
26-May	moderately	11:29 PM	W/NW	11:34 PM	NE
27-May	moderately	10:36 PM	W/NW	10:41 PM	NE
28-May	moderately	12:13 AM	NW	12:18 AM	NE
28-May	moderately	9:43 PM	W	9:49 PM	NE
28-May	moderately	11:21 PM	NW	11:25 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.

Meteor showers: Eta Aquariids April 20 to May 20, peaking May 5 and 6

The Eta Aquariid radiant, complete with Venus, Saturn, the newly returned Summer Triangle, and one perfectly-placed 5 a.m. ISS flyover on the morning of May 6

The Eta Aquariids are believed to be due to the great Halley's Comet, although there is some debate as to whether Halley's Comet produced the debris or gravitationally nudged debris into the current area. If it is all Halley's debris, then Halley's elliptical path around the sun produces two meteor showers – the second being the Orionids in October.

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. When there are multiple meteor showers associated with the same constellation, the radiant is traced back even more accurately, right down to one of the stars in that constellation. There are seven meteor showers associated with Aquarius, but only two produce decent meteor showers. The Eta Aquariids appear to originate from very close to eta-Aquarius, although zeta-Aquarius is quite close as well.

How to observe: The Eta Aquariids are a long, gradual meteor shower that stretches over about 30 days. There is no sharp peak, only a predicted maximum around May 5th and 6th, with decent viewings possible from the 3rd to the 8th. The constellation Aquarius sits quite low on the horizon in the early mornings in early May and is not particularly prominent either. Depending on when you try to observe, Venus would serve as an adequate marker, else find the Summer Triangle high above and look half the distance to the horizon. To optimize your experience, lie flat on the ground with your feet pointed to the southeast and your head elevated – meteors will then appear to fly right over and around you.

Those interested in seeing a full list should check out the American Meteor Society meteor shower calendar.

Learn a Constellation: Cassiopeia

Cassiopeia and Cepheus in the late-evening May sky.

Our northeast-facing image in the Evening and Nighttime Guide above shows the Big Dipper marked in green and an arrow pointing towards Polaris in the Little Dipper. If we extend that arrow down another full length, we end up pointing near the Cassiopeia/Cepheus divide. Those with either a background in Greek mythology or ticket stubs to one of the two versions of "Clash Of The Titans" will know that these two constellations come as a pair – King Cepheus, ancient ruler of Aethiopia, and Queen Cassiopeia, who offended the gods by boasting of her or her daughter Andromeda's beauty.

During pre-midnight observing hours in May, Cassiopeia may remind you of something from a different movie – the 1963 comedy "It's a Mad Mad Mad Mad World." Towards the end, Jonathan Winters is seen slowly turning around to identify one of the key plot points – a "Great Big W." Cassiopeia's motion around Polaris cleanly breaks into four groups that are easy to remember – from May to July, it's a "W" at the horizon, from August to October, a "3" in the northeast, from November to January an "M" high in the north, and from February to April an "E" in the northwest. Its five stars are very bright, but if the shape doesn't reveal itself the first few times, simply use the Big Dipper, find Polaris, and continue unit a W, 3, M, or E jumps out.

The five bright stars of the "W" asterism are all observing-worthy on their own. Caph is a variable star spinning so fast that it is 25% wider at its equator than its poles. Schedar is a four-star system. Navi is an unpredictable variable star whose brightness you can keep track of without any magnification. Ruchbah is an eclipsing binary star – which means one star goes right between us and the main star as it orbits every 25 months, causing a quick, predictable drop in the brightness. Finally, Segin is noteworthy for the shell of gas surrounding it, giving its spectrum a more complicated shape.

For the binocular observers, there are two Messier Objects to find – the open star clusters M52 and M103. Both of these might be more prominent in another part of the sky, but Cassiopeia lies just in front of a thin band of the Milky Way. As a result, binocular and telescope observers end up seeing a wealth of stars in the background as they scour for deep sky objects.

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:

2012 venus transit, big dipper, cassini mission, cassiopeia, cepheus, eta aquariid meteor shower, eta aquariids, great big w, m103, m52, orionids, solar eclipse, venus

March 24, 2012September 23, 2018

Some Light Science Reading. The Constellations: Ursa Minor

As first appeared in the January/February/March 2012 edition (yeah, I know) of the Syracuse Astronomical Society newsletter The Astronomical Chronicle (PDF) and, I am proud to say, soon to be included in an edition of the Mohawk Valley Astronomical Society (MVAS) newsletter, Telescopic Topics.

Image generated with Starry Night Pro 6.

[Author's Note: A tradition owing to Dr. Stu Forster during his many years as President and Editor, the Syracuse Astronomical Society (www.syracuse-astro.org) features (at least) one Constellation in each edition of its near-monthly newsletter, the Astronomical Chronicle.]

The Constellation discussion for this year is going to take a bit of a turn.

As part of the 2011 Syracuse Astronomical Society (SAS) lectures presented at Liverpool Public Library and Beaver Lake Nature Center, I spent a few minutes covering (briefly) how to navigate the Night Sky. By way of introduction, I described how one of my graduate advisors, Dr. Bruce Hudson, began scribbling furiously a long string of quantum mechanical equations about something-or-other that devoured the lion's share of a whiteboard. Upon mentioning that I had no idea how he kept such information at the ready in his noggin, he replied "Try doing it 50 years."

It is, in my humble opinion, useless to present the 88 Constellations to a general, new-to-observing audience in an hour and expect anyone to remember information that I, as el presidente, am still trying to digest after several years (a problem made all the more infuriating by the fact that this information hasn't changed in several millennia). The problem that I and others at this latitude have is that the vast majority of the Night Sky changes throughout the year and, given that weather conditions often result in short spells of clear sky and long patches of overcast conditions, there is often little opportunity for "mental reinforcement" to help commit the lesser (well, at least smaller or dimmer) Constellations to memory.

The solution I discussed in the lectures was to play the "observability odds" and focus on learning those Constellations that you can, given clear skies, see all year long from Central New York (CNY). This group of Constellations are defined as "circumpolar" and, by their location about the axis of rotation of the Earth, never dip below the West/Northwest Horizon (or, at least, they do not entirely disappear over the course of a long evening of observing unless you're surrounded by considerable foliage).

The set of images at the end of this article will show you how to kill six birds with one long, clear turn of the stone we call Earth. The small family of six Constellations I've included in this discussion are (1) Ursa Major (although, here, I'm only including the Big Dipper asterism for ease of identification. This is obviously a better target for new observers), (2) Draco the Dragon (a long and winding Constellation that is curled around the Little Dipper), (3) Cepheus, the late-late-late King of Ethiopia (as much as I dislike the use of simple geometric objects to identify groups of stars (because, well, they're all points on imaginary polygons), the odd pentagon does stand out at night), (4) Cassiopeia (Jonathan Winters' Big "W" and, thanks to Earth's rotation axis, also sometimes a "3," or an "M," or an "E," but obvious upon first being pointed out), and (5) Camelopardalis the giraffe (one of the last Constellations you might otherwise learn. Also one of the last Northern Constellations marked as such, in this case in 1612 by Petrus Plancius. You might even have a little trouble picking this one out. The Greeks (for instance, and in their infinite wisdom (I note with a 100% Greek heritage)) did not even bother to identify anything in this part of the sky as being of significance given how relatively dim the stars are). This list leaves number six, Ursa Minor, which I denote in the images as "0" as your celestial clock face base of operations.

Ursa Minor, or the Little Dipper (below, shown at its approximate orientation at 10:00 p.m. on March 23rd), is a nondescript Constellation that requires a bit of searching to find in the Night Sky. Polaris, its last handle star (2.0 mag.), is made easier to find by the fact that it is in a very dark, very nondescript piece of sky (it is identifiable simply by being where it is). Its cup-edge stars Pherkad (3.0 mag.) and Kochab (2.1 mag.) are a bit brighter and also in a dull region of the sky. The four remaining stars are the ones that become more visible as you mark their location with your scanning eyes. These four are made a bit more difficult to find from Darling Hill Observatory (home of the SAS) because of the bright light bulb directly at our Northern Horizon that is downtown Syracuse.

A possible trick to finding Polaris for the new-at-observing is to use the two most prominent Constellations in the North, Ursa Major (again, using the Big Dipper asterism here) and Cassiopeia. Finding the bowl of the Big Dipper and imagining a clock face, find Cassiopeia at nearly 7 o'clock to the edge-most bowl stars, then aim for the location where you'd expect those hands to be riveted (as shown below). Again, you'll find a single bright-ish ("eh") star at this location.

Having sufficiently talked down the significance of Polaris as a celestial observable, this otherwise nondescript star has something other nondescript stars have. To quote "Glorious John" Dryden:

Rude as their ships were navigated then;
No useful compass, no meridian known;
Coasting they kept the land within their ken;
And knew no North but when the Pole star shown.

Or, as William Tyler Olcott sums more quickly in his book "Star Lore," Polaris is "the most practically useful star in the heavens." Modern civilizations know Polaris as the star around which the Earth appears to spin, making it the most stably-placed object in the Night Sky over any reasonable span of human existence (a qualification I use in this article to avoid a discussion of the fascinating but "not relevant to learning the Night Sky right now" Precession of the Equinoxes).

The apparent constancy of all of the star positions (and Constellations) in the Night Sky relative to one another is, of course, due to stellar parallax, the celestial equivalent of the more familiar terrestrial parallax. If you've ever been the passenger on a long drive, you've borne witness to the trees along the road moving at a tremendous clip while the distant trees slide far more slowly through your field of view (that is, stay in your field of view while the trees along the road fall far behind you over the same amount of time). Polaris provides an ideal example of this same phenomenon on a celestial scale by its apparent immovability in the Night Sky despite the best efforts of Earth as it reaches nearly 300,000,000 kilometers of physical separation from its starting point every six months. The two images below demonstrate the phenomenon…

Your Green Laser Along Earth's Rotation Axis (Pointing UP From The North Pole), One Beam Every Three Months, Separated By (At Best) 2 Astronomical Units (a.u.), Looking At A "Close Object" With A Large Apparent Motion Against The "Background"

Your Green Laser Along Earth's Rotation Axis (Pointing UP From The North Pole), One Beam Every Three Months, Marking A Position 431 Light Years Away (Looking At A "Distant Object") And A Small Apparent Motion Against The "Background" (All NOT To Scale)

At above-left you see a small slightly-sideways model of Earth's motion around the Sun (at points being marked about every three months), with the left-most and right-most positions separated by two astronomical units, the astronomical unit being the mean distance between the Sun and Earth (bearing in mind Kepler's Elliptical description of our orbits), a value of about 150 million kilometers. To objects in our own Solar System or even a few nearby stars, this large change in position is enough to clearly see those objects that are nearby move more than the "background" of more distant objects (you could do this at home with a decent scope and excellent note-taking skills, possibly reproducing the 1838 work of Friedrich Bessel in his measurement of the parallax of 61 Cygni). In our case, the more distant objects are the stars far from our vantage point (think of "stars" as "trees" and the same driving analogy works, although now you're driving around a circular track and paying your passenger to always look North). Polaris, as measured by the Hipparcos satellite (using parallax to exacting detail), determined that Polaris is 431 light years away, a distance of 27.5 million a.u.! And this is a CLOSE star considering the 100,000 light year diameter of the Milky Way. At this distance, if the four green laser pointer beams were a meter long, their separation in Earth's orbit would be a small enough measuring distance to map out the contents of a single-celled organism in exacting detail. My ability to draw a proper parallax-like image to show this is limited by the pixels on my screen being gigantic compared to the apparent change in position in this crude image (so the above image is decidedly NOT to scale).

All of this discussion above is basically to convince you that, when you look up in the Night Sky, Polaris will effectively NOT move to the best of your ability to observe it, making it a best starting point for your Constellation memorization adventure.

Well, Polaris will NOT move provided you always observe from the same latitude on the Earth's Surface. The last piece of the puzzle to put ourselves into proper perspective comes from a zoom-in of our Earth, shown below. You'll see that our North Pole, appropriately placed at 90o North Latitude, is aligned nearly exactly with Polaris (again, for our purposes, this approximation is fine). What does that mean? It means that, with the right low Horizon (or high hill), nearly ALL of the Northern Constellations are circumpolar at the North Pole! Think of the memorization mess! Alternatively, at the equator (0o), the Night Sky is, effectively, constantly in motion (this should make you truly appreciate the navigational and astronomical skills of the Polynesians in their spread across the South Pacific islands).

As you walk from the Equator to the North Pole, moving from 0o to 90o North Latitude, the North Star appears to get higher and higher in the Night Sky. By this, the angle of Polaris above the Horizon (its altitude) is equal to our latitude (so when you know one (say, by getting your latitude and longitude from google maps or the like), you know the other. This is one of the great "then explain this, dummy!" rhetorical smack-downs to members of the Flat Earth Society). In our case, Polaris is about 40o above our horizon. Personally, I think 40o North Latitude is a perfectly reasonable place to begin Constellation memorization. Not too many, not to few. And, as is the common theme we'll explore this year, once you have a reliable base of celestial operations, learning the remaining Constellations becomes a significantly easier (but still Herculean) task.

The Counterclockwise Circumpolar Map

Your Northern Horizon from CNY will, clear skies permitting, ALWAYS look something like the following, with the Constellation closest to the N/NW Horizon labeled as follows (0 = Ursa Minor, the Little Dipper. * = Polaris, which appears to not move (to a coarse approximation)):

A. Big Dipper (1, technically, Ursa Major, but the Big Dipper is smaller and more obvious)

B. Draco (2, aim for the dragon's head. If the Big Dipper is N/NE, an easy find)

C. Cepheus – 3, a crazy house standing upright, just right of a bright "E"

D. Cassiopeia – 4, the big "W," at the horizon an "E" (or its canonical chair)

E. Camelopardalis (?!) – 5, the back-end of a giraffe(with Cassiopeia as a "Big W," the giraffe is drinking from the tipped bowl of the Big Dipper).

NOTE: The Earth's rotation makes 1-to-5 move counterclockwise! Fresh Constellations over your Eastern Horizon, stale ones disappear at your West.

Happy Hunting – Damian