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Click here to download the November 2017 PDF version

 

In the warmest month of spring, explore the heavens with:

The Australian Night Sky - November 2017

By Wayne Roberts

What's In The Sky This Month

The Planets

Our Monthly Feature

 

[Click here to show or hide the explanatory notes]
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What's in the sky this month; November 2017:

 4th Full Moon.
 6th Moon at perigee (closest to Earth, 361,438 km);
     Aldebaran (Alpha [α] Tauri) occulted by Moon (not from Australia).
11th Last quarter Moon.
12th Taurids North meteor shower peaks;
     Regulus (Alpha Leonis) occulted by Moon (not from Australia).
16th Asteroid 4 Vesta occulted by Moon (not from Australia).
17/18th Leonids meteor shower peaks.
18th New Moon.
22nd Alpha Monocerotids meteor shower peaks;
     Moon at apogee (farthest from Earth, 406, 132 km).
23rd Neptune stationary (ends retrograde motion).
24th Mercury at greatest elongation east, 22°.
27th First quarter Moon;
     Neptune occulted by Moon (not from Australia).

N.B.: When reading the following, refer back to the explanatory notes at the beginning of this article (click on the above link to expand) for information on terminology, angular separation approximations and adjustment of latitude & longitude.

The Moon occults two stars, an asteroid and a planet this month; unfortunately, none of these events can be witnessed from Australia. First to have our only natural satellite slide in front of it, on the 6th, is Aldebaran, which is occulted from NW Asia, N. Europe and all but the far west of Nth America. For us, the limb of the Moon is never closer than a little less than 1° (as a rough guide, one finger held at arm’s length spans a little over 1°, a closed fist 10°, an open hand, tip of little finger to thumb tip, 20°) from the star, and this occurs a whopping 64° below the SSW horizon, at 1:51 pm.

Second cab off the rank is Regulus, on the 12th, the occultation of which can be witnessed from Japan, Central America, SW North America and east Asia. Locally, closest approach is at 2:36 am; the star is four minutes short of breaching the ENE horizon and is again a little under 1° from the Moon’s limb. One hour later, Regulus is 10° above the horizon and a touch over 1° above the dark limb of the 41% lit waning crescent Moon, almost in the direction that the terminator (the ‘line’ separating the lit and unlit portions of the lunar disk) points.

Next to experience a dalliance with the Moon, on the 16th, is 4 Vesta, the brightest asteroid in our skies (99942 Apophis will be brighter during a close pass to Earth in 2029; it’s an interesting object, google it for further information). While Vesta is obscured by the Moon from our perspective, the event, which occurs between 8:26 pm and 9:14 pm, takes place below our SW horizon, with the asteroid at altitudes of -27° and -34° respectively.

On the 27th, it’s Neptune’s turn to disappoint us; it at least has the decency to do so above our horizon (at an altitude of 24° in the ENE), albeit in daylight. It sits just over ½° NE (below left) of the 56% illuminated waxing gibbous Moon’s limb at closest approach, 3:25 pm; as was the case with Regulus, Neptune is off the Moon’s dark limb, not far from the direction indicated by the terminator.

Three meteor showers climax this month, the Taurids North on the 12th, the Leonids on the 18th (and perhaps a day earlier) and the Alpha Monocerotids on the 22nd. The first of these, generated by debris from comet Encke, is of least interest, as the ZHR is 5 at best, more probably 2 or less on this occasion, and the 41% illuminated Moon rises at 2:44 am, interfering with much of the preferred early morning viewing times. As a matter of interest, these meteors tend to propagate relatively slowly across the sky; the International Meteor Organization (IMO) states that there is another shower with a radiant not far to the east, which it calls the November Orionids, and meteors from this shower are considerably swifter, distinguishing them from the Taurids North. Starry Night software shows no shower by the name of the November Orionids; it does show the Chi Orionids to the east of the Taurids, but these are slow, not swift. Obviously my understanding is lacking here, and the above information is only included as food for thought.

The Leonids, generated by comet 55P/Tempel-Tuttle, are a different matter altogether (I’ll never forget the Leonids meteor storm around the turn of the century, witnessing hundreds of meteors over the course of a few hours in the early morning, and continuing to watch them flash across the sky on the drive to work), as the expected hourly rate is around ten, and the Moon is out of the sky for much of the post-midnight hours. This year’s shower is expected to peak at 3:30 am on the morning of the 18th; the IMO indicates that there is also a possibility of another brief maximum centred around 4:07 am the previous morning.

The following chart depicts the radiant of all three of this month’s showers at 3:30 am on the 18th; the Leonids’ radiant is at an altitude of 6° in the NE, having risen in the ENE at 2:55 am. The Moon is out of the sky altogether, as the 18th coincides with New Moon.

The radiant of the Alpha Monocerotids is also shown, at an altitude of 44° in the NE. This shower peaks at 4 am on the morning of the 22nd, at which time it will sit 48° high in the NNE; it can be expected to yield 2-5 meteors per hour, but has been known to produce outbursts, most recently in 1995, at a rate of 420 per hour over a brief five minute period. While the next outburst is not expected until the year 2043, the shower is regarded as one which can spring surprises. The radiant crests the eastern horizon, on the evening of the 21st, at 11:06 pm, and rises ever higher in the sky; additionally the Moon co-operates by setting a little over ½ hour earlier, at 10:31 pm, so avid meteor watchers may be rewarded.

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THE PLANETS

Mercury

Mercury begins the month in evening twilight, climbing out of it (i.e. setting after it finishes) on the 14th, and dwelling in a dark sky for almost two weeks before re-entering twilight on the 27th. On the 1st, it’s at an altitude of 13° WSW at sunset, 7:55 pm, before setting at 9:09 pm; its 92% illuminated disk spans 5" and shines at magnitude -0.4.

The choice of viewing night is straight forward this month, with New Moon falling on Saturday 18th. On this date, Mercury has just barely cleared twilight, being ½° above the SW horizon as the sky fully darkens at 9:59 pm, and setting four minutes later; the span of the disk is out to 6", 75% lit, and it shines at magnitude -0.3.

The planet reaches its greatest angular separation from the Sun in our sky (“greatest elongation east”) on the 24th as its slowing eastward movement against the background stars is overtaken by the Sun’s own relentless such progress. For the remainder of the month and into December, Mercury closes on Saturn; unfortunately, the low altitude of the pair (with Mercury re-entering twilight on the 27th) compromises the view, but the innermost planet’s brightness, magnitude -0.2 on the 27th, will render it visible to the naked eye through the glow of twilight. Both planets will show up in the field of view of binoculars or a finder ‘scope; here’s the view on the 27th at 9:08 pm, ¾ hour after sunset, with Mercury and Saturn at altitudes of 10½° and 9° respectively:

After the 27th, Mercury will swing up and to the east (right), then down for an even closer conjunction with Saturn on the 6th and 7th of next month; details in December’s ANS.

On the final day of November, Mercury sets (in twilight) at 10:06 pm, having been at an altitude of 17° in the WSW at sunset, 8:26 pm; span and phase are 8" & 42%, and the planet shines at magnitude 0.0.

The genesis of Mercury’s designation as the Messenger of the Gods is on display this month as it flits between the constellations – beginning the month in Libra, it crosses into Scorpius on the 6th, Ophiuchus on the 12th, back into a corner of Scorpius on the evening of the 15th, recrosses into Ophiuchus in the early hours of the 17th, and then moves into Sagittarius on the 27th.

Venus

Venus is deep in morning twilight this month, the more so as the month progresses; any other planet would struggle to be seen in the brightening sky, but Venus’ brilliance will render it a naked eye object throughout the month, albeit very close to the eastern horizon. As November begins, it rises at 5:36 am, and is just 7° high in the east when the Sun rises at 6:13 am; shining at magnitude -3.93, its 10.3" disk is 96% illuminated.

As Venus loses altitude daily, Jupiter rises to meet it – the two brightest planets have what would be a stunning conjunction on the mornings of the 13th and 14th, were it not for their proximity to the Sun and subsequent very low altitude in the morning sky. Here they are ¼ hour before sunrise, ½° apart, with Venus just 3° above the horizon. If you are tempted to target this conjunction through binoculars or a telescope, which I do not suggest, make sure the Sun remains below the horizon to avoid the prospect of permanent eye damage should it enter the field of view.

A worthwhile exercise, and one devoid of the dangers expressed above, is to try and follow Venus down to the horizon with the naked eye before sun-up as it moves towards conjunction early in January. To this end, its rise time and that of the Sun, together with its altitude at sunrise on the 19th (the morning after our viewing night) and the 30th are respectively: 5:25 am, 5:57 am, 5.6° and 5:23 am, 5:52 am, 4.8°.

Beginning the month in Virgo, Venus crosses into Libra just after midnight on the night of the 13th/14th, and remains in that constellation for the rest of November.

Mars

Mars’ slow climb into the morning sky finally sees it rising before the commencement of morning twilight this month, on the 20th. At the start of the month, it rises at 4:55 pm, still almost twenty minutes after the sky begins to brighten (4:36 am), and a little over 1¼ hours before sunrise, 6:13 am, by which time it has climbed 15° clear of the eastern horizon. The Red Planet’s disk is nominally short of full illumination, at a phase of 97.3%, spans 3.9" and shines at magnitude 1.79.

Come the morning of the 19th (following our nominated viewing night), Mars is on the verge of rising in a dark sky; it crests the eastern horizon at 4:12 am, just one minute after morning twilight commences, and has attained an altitude of 20° by the time the Sun rises at 5:57 am. Mars’ disk is slightly less illuminated, 96.3%, and marginally larger and brighter – 4.1" and magnitude 1.73.

By month’s end, rise time has come forward to 3:46 am, ¼ hour short of the start of twilight (4:01 am), when it’s 2½° high in the east; phase, span and visual magnitude stand at 95.5%, 4.2" and 1.68.

Mars resides in the constellation of Virgo throughout November.

Jupiter

Having been in conjunction with the Sun – rising and setting with our local star and thus unobservable – late last month, Jupiter’s status in the observability stakes ranges from hopeless at the start of November to poor at the end. As its only remotely inviting circumstance this month – a dalliance with Venus deep in twilight – has been described earlier, coverage here will be confined to basic statistics only, for selected dates, as per the table: Jupiter follows Venus from Virgo into Libra on the 15th, where it will remain for the next twelve months.

Saturn

This memorable evening apparition of Saturn and its eye catching ring system – tilted near its maximum of almost 27° throughout – is drawing to a close, the planet setting in evening twilight after the 24th. Even on the first day of November, Saturn’s altitude as twilight wraps up at 9:33 pm is just 21°, and so considerably less than the 30° from the horizon this column normally counsels as a means of avoiding looking through more of our turbulent atmosphere and the murk that lies near the horizon. Subsequently setting at 11:31 pm, Saturn’s disk and rings span 15.5" and 35.2" respectively, the rings angled at 26.97°; together, disk and rings shine at magnitude 0.54.

On the 18th, our viewing night, the situation has deteriorated further – Saturn is then just 25° high at sunset, 8:13 pm, and a mere 5° when the sky fully darkens, 9:59 pm, before setting at 10:32 pm. The span of the disk is down to 15.2" as its distance from Earth increases, and that of the rings to 34.6", inclined at 26.91°. The below chart shows a wide angle view at 9:59 pm (the cessation of twilight); Mercury is labelled to emphasise the degree to which the innermost planet closes on Saturn (in our sky) between the 19th and 27th (see the Mercury notes above), and Pluto is also labelled for later reference.

Next is a magnification showing Saturn’s seven brightest moons, although the low altitude once the sky has fully darkened is not conducive for telescopic views of them:

Top to bottom, the moons shine at the following visual magnitudes: Iapetus 11.8, Titan 8.9, Dione 11.0, Rhea 10.3, Enceladus 12.3, Mimas 13.5 and Tethys 10.8. All brightness ratings except the first are taken from Starry Night software; that for Iapetus is my (confident) estimate, necessitated by the software not accounting for the variation caused by the differing albedo (reflectiveness) of the moon’s opposing hemispheres. Were the planet high in the sky, bright Titan would show up easily in any telescope; Rhea, Tethys and Dione should yield to a six inch ‘scope, Iapetus and Enceladus may call for an eight incher, while Mimas would require a ten or even twelve inch. Bear in mind the compromising nature, however, of the low altitude, which may make the moons difficult to see.

The vast majority of the stars shown are 16th magnitude or fainter, as indicated by the size of their markers; they will not be visible on other than a scope with very large aperture. The components of the double star to the lower left, on the chart, of Rhea shine at mags 12.75 and 13.4; as they are only separated by 2.7", they may appear as one, effectively glowing at mag 12.3. The brightest stars near far flung Iapetus (to its right on the chart) are of 15th magnitude; the moon will therefore stand out if viewing conditions permit. Note the circled double star short of Iapetus; its components, shining at mags 12.25 and 13.4, are just 1.4" apart and will appear, through most ‘scopes, as one star of mag 12.0; care must be taken not to confuse them (it) for the moon. While the star to Titan’s upper right is relatively bright at mag 12.2, it is very dim compared to the moon and so cannot be mistaken for it. Note that while the software performs well with regard to denoting brighter stars as larger than their dimmer brethren, it is found wanting in its treatment of moons, with all those shown here, other than Mimas, depicted at the same size; that is the reason why the aforementioned star near Titan is depicted almost at the same size as the moon, while in fact being far dimmer. Come the end of the month, Saturn is setting in twilight; it is only 15° high as the Sun sets at 8:26 pm, and sets itself at 9:50 pm. Visual magnitude stands at 0.50, disk span 15.1", ring span and inclination 34.3" & 26.85°.

The astute reader may have noticed that Saturn brightens throughout the month, despite receding from Earth (as the declining span of disk and rings testifies) and nearing conjunction with the Sun (Dec 22nd). This is currently one of nature’s little mysteries, one which I first addressed last November and again in January & February this year; consult the viewing notes for these months (archived on the ASV’s web page) for discussion of possible causes of this counter intuitive behaviour.

Saturn transitions from Ophiuchus into Sagittarius on the 19th, and will remain in that constellation until 2020 (albeit spending 3½ months in early-mid 2020, as well as half of December of that year, in Capricornus).

Uranus

Uranus having been at opposition last month (on the 20th), November and the months to come provide the best opportunity to catch views of the planet, and at an increasingly convenient time of the evening. On November 1st, the ice giant is 13° clear of the horizon at sunset, 7:55 pm, 30° at the end of evening twilight, 9:33 pm, and then transits – reaches its greatest altitude, 43° in this case – at 12:13 am; its disk, which spans 3.7" all this month, shines at magnitude 5.69.

As we set up our ‘scopes on the night of the 18th, the above times have come forward to 8:13 pm, 9:59 pm and 11:04 pm, at altitudes of 28°, 41° and 43° respectively. Uranus then sets at 4:37 am, just under half an hour after the commencement of morning twilight (4:11 am); brightness has improved nominally, to mag 5.70. Here’s an overview, configured for transit on the 18th, showing where it sits in the sky, with Neptune also benefitting from the exercise:

Begin your search by identifying the Great Square of Pegasus, with Algenib (Gamma [γ] Pegasi, mag 2.8) and Markab (Alpha Peg, mag 2.5) at its top right and left corners respectively. The Square, whose sides span between 16½° (Markab-Algenib) and 13° (Markab downwards) stands out in the northern sky; remembering that a closed fist at arm’s length typically spans around 10° may be of assistance in identification. Use the Square to identify Eta [η] Piscium, 19° from Algenib and a little fainter at mag 3.59, but still a very comfortable naked eye target. Eta should stand out as the only naked eye star in its immediate vicinity (the chart approximates a naked eye view); the two brighter stars to its lower right point to it, further aiding in identification. It may also help you to orientate yourself by noting that the ‘smudge’ half way up the far right of the chart is the Pleaides, aka the Seven Sisters.

From Eta, look 7° to its upper right for the yet fainter, but still comfortably naked eye, Omicron Psc, mag 4.25. You may find it useful to confirm Omicron’s identity by noting that it lies almost exactly on a line from Algenib to Kaffalijidhma (Gamma Ceti, mag 3.5), the unlabelled but circled star next to Menkar (Alpha Ceti, mag 2.5) in the constellation figure of Cetus. Menkar itself is the brightest star in its part of the sky, for more than 20° in any direction, and you should be able to make out the constellation figure as shown without too much effort. Having located Omicron, proceed to the final magnification below to nail your planetary quarry.

This chart, which labels stars with their visual magnitudes, is delimited by Eta Psc (‘3.59’) at bottom and Omicron Psc (‘4.25’) at top. It is intended to be used in conjunction with a finder ‘scope; as such it shows stars down to magnitude 9.5, a little fainter than a typical view through such an instrument. Two other stars are labelled to help you relate the chart to what you see in the sky; Pi [π] Psc, mag 5.53, is faintly visible in the earlier overview, and HIP 8588, at mag 5.90, is just marginally fainter than Uranus. Depending on your finder ‘scope, the rough quadrilateral of Uranus, ‘4.25’, 5.90’ and ‘5.53’ should fit, or very nearly so, within the field of view; Uranus is 2¾°, 4½° and 3° from them respectively (the width of a finger at arm’s length typically spans a little over one degree). The planet is brighter than all unlabelled stars on the chart, and will tend to betray its planetary nature courtesy of a subtle blue-green hue and a steady shine relative to the twinkling stars. Note the white crosses denoting Uranus’ location on the first (right) and last (left) days of the month.

When you think you’ve found your target, examine it through the main eyepiece of your ‘scope using a magnification of 150x or more – the higher the better, providing the view stays crisp – to confirm capture by resolving its disk; you will be pleasantly surprised by the considerably richer colouration than that detected through the finder ‘scope.

At the end of November, Uranus shines at mag 5.72, and is 36° high at sunset, 8:26 pm; it transits at 10:16 pm, just as twilight ends, subsequently setting at 3:49 am. Moving slowly in its orbit far from the Sun, the planet will remain in Pisces until 2018/19.

Neptune

This apparition of Neptune is past its prime, the planet transiting before evening twilight expires, but it is nevertheless still well positioned for viewing. As the month begins, it transits at 9:30 pm, three minutes before twilight ends, then sets at 3:57 am; spanning 2.3" throughout the month, Neptune’s disk shines at magnitude 7.85.

Come the 18th, the planet is transiting at 8:23 pm, just 10 minutes after sunset, subsequently setting at 2:50 am; its brightness has deteriorated incrementally to mag 7.87. The wide field chart for Uranus shows where it sits in the sky; using that chart, identify the asterisms shown – the Great Square of Pegasus, the Circlet of Pisces above it and the ‘Y’ of Aquarius to the left of the Circlet. Both the Circlet and ‘Y’ are composed primarily of 3rd and 4th magnitude stars and so are easily, though a little dimly, visible to the naked eye. Beginning then from the ‘Y’, identify the star Lambda [λ] Aquarii, magnitude 3.71, 10° away in the direction shown; as the field between the ‘Y’ and Lambda appears virtually empty without optical assistance (the one star shown, Kappa [κ] Aqr, is itself very dim, at magnitude 5.03), and Lambda is considerably brighter than any star near it, identification should not be difficult.

Refer then to the following magnification, configured for 10:30 pm (on the 18th), which shows stars down to about magnitude 13.8 and labels them with their brightness ratings; it is delimited by the mag 8.34 star (HIP113059) near Lambda at bottom right and the field beyond Neptune at top left. Note that Neptune will not noticeably change its distance from the various stars in the field (under other than very high magnification) during the course of the evening, but the orientation will change as the planet arcs across the sky; it is for this reason that the time is specified here.

As the chart shows, there are only very faint stars between Lambda and Neptune, star and planet being separated by 0.65° – if you centre Lambda in your finder ‘scope, which typically will have a field of view of a little under 5°, the planet will be obvious as a ‘star’ very close to it – don’t mistake it for the HIP designate mentioned above, even closer but on the other side of Lambda. As with Uranus, Neptune’s colouration – a subtle blue-grey – and steady shine will help to identify it. This should suffice for identifying the planet, but you may wish to adopt the alternative strategy of fitting a medium power eyepiece which will show the star field, all members of which, other than the two 9th magnitude stars, will be too dim to have been seen through the finder (even those two will be at or near the limit of visibility); the star of magnitude 11.71 is labelled to emphasise how bright Neptune is compared to the nearby stars.

Note that the chart includes white markers plotting Neptune’s position on the first (labelled F) and last (L) days of the month; the actual marker for the 30th is partially obscured by the ‘N’ of Neptune’s label. Note also that the planet ceases retrograde motion (see the explanatory notes at the beginning of these viewing notes) on the 24th, thus explaining why its plotted position of the 18th is further to the left on the chart than is the marker for the 30th. When you have Neptune in your sights, use the highest practical magnification – I suggest 250x or more – to confirm capture by resolving its tiny disk.

On November 30th Neptune transits in broad daylight and sets at 2:03 am (on Dec 1st); it will remain in Aquarius until 2022/23.

Pluto

As flagged last month, this apparition of remote Pluto has effectively run its race, with the planet far from the preferred, if not requisite, altitude after evening twilight is extinguished. While the beginning of the month sees it remaining at an altitude of 40° as twilight fades at 9:33 pm, this column has always counselled viewing the tiny orb under a dark sky close to the zenith; with the 90% waxing gibbous Moon high in the sky, neither condition is met. Consequently, in this and coming months, detailed finder charts will no longer be provided. For the record, Pluto sets at 1:06 am (on the 2nd), and its miniscule disk spans 0.094", glimmering gently at magnitude 14.32, a brightness rating it maintains throughout November.

When our viewing night of the 18th arrives, Pluto’s altitude at the end of twilight, 9:59 pm, is a disabling 22°; setting at midnight, its disk has shrunk a little further, to 0.093". Looking back at the wide field chart in the notes on Saturn, you’ll see where Pluto sits in relation to the Teapot asterism of Sagittarius, and in particular to the three naked eye stars nearby. The following enlargement – configured for 9:59 pm on the 18th – of the field encompassing these stars and Pluto will not suffice to pinpoint the planet, but gives a good indication of where it lies.

The white cross below left of Pluto plots its position on the 1st; that to the upper right is for the 30th. The three naked eye stars referred to above are labelled in this chart and shine at the following visual magnitudes: Albaldah (Pi Sagittarii) 2.9, Omicron [ο] Sag 3.75 and Xi22] Sag 3.5. The lower of the two circled stars is HIP94372 and that above is HIP94510; they shine at magnitudes 6.4 and 7.0 respectively, and will be prominent in a finder ‘scope.

On the last day of the month, Pluto is but 10° high as the sky fully darkens at 10:16 pm, setting less than an hour later, at 11:14 pm; span (and brightness) remain as at the 18th.

Pluto will remain within Sagittarius until 2023/24.

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Our Monthly Feature

This month’s feature is the globular cluster M2, aka NGC 7089. It was first discovered by the French astronomer Jean-Dominique Maraldi on Sept 11th, 1746, while looking for a comet; quite coincidentally, Charles Messier independently came across it exactly fourteen years later, also while comet hunting (it subsequently became the second object on his list of non-comets, hence its designation of M2). Neither could resolve stars within what appeared as a nebulous object, but interestingly Maraldi’s notes at the time indicate that he regarded the haziness as suggestive of unresolved stars; the British astronomer William Herschel was the first to resolve stars within the globular, in 1783.

M2, located some 37,500 light years (l.y.) away, is among the largest and oldest of globular clusters, spanning about 175 l.y. and containing around 150,000 stars, but its dense central region spans “only” around 3.7 l.y. (compare that with the fact that our Sun’s nearest neighbour is over 4 l.y. away!). Spectroscopic analysis indicates it is currently approaching us at 5.3 km/sec, but as both parties revolve around the Milky Way, this is a transient statistic, which will change over time.

Finding M2 is not at all difficult, quite easy in fact if gone about in the correct manner; refer to the chart below, which is configured for our viewing night of the 18th at 9:59 pm, the cessation of twilight (my apologies for the fact that a couple of other charts in these viewing notes are configured for this time; while it’s a sensible time to suggest viewing an object which has already transited earlier in the evening – M2 transits at 7:04 pm on the 18th – obviously they can’t all be viewed at once).

Some forums suggest that the best way to locate M2 is to first identify the stars of magnitudes 2.87 and 2.93, respectively Sadal Suud (Beta [β] Aquarii) and Sadal Melik (Alpha Aqr). This is a valid approach, but while these two stars are brighter than others around them, they don’t stand out in a pronounced fashion; the following approach (which involves Sadal Suud) works better, in my opinion:
First identify the Great Square of Pegasus, which was also the suggested starting point in the search for the planets Uranus and Neptune; it’s no coincidence that this star pattern has been referenced in these notes a number of times, the simple fact is that it’s easy to pick out in the night sky.

Focus then on Algenib (Gamma Pegasi, mag 2.81) and Markab (Alpha Peg, mag 2.46), the two stars at the top of the Square. Scribe, in your mind’s eye, a line from Algenib to Markab, then extend it by just a little more than its own length, while veering very slightly to the right, to arrive at Enif (Epsilon [ε] Peg, mag 2.37), which will be very easy to identify. From Enif, veer right again, this time at 60°, to arrive at the aforementioned Sadal Suud, mag 2.87, about as far from Enif as Markab is from Algenib. M2 is then at your mercy, about ⅓ of the way from Sadal Suud to Enif, and almost exactly on a line joining them; the best approach is to first target this area through your finder ‘scope to identify the globular, but you may prefer to sweep the appropriate patch of sky through the main eyepiece at low power.

While I suggest using the finder first, a word of caution is in order – although the globular will be readily seen through your finder, and definitely will be in the field of view if you are looking at the area indicated in this text and on the chart, it will only appear as a fuzzy, slightly oversized star, not as a globular per se. Look carefully at the star field, and you’ll soon see the tell-tale fuzzy nature of one ‘star’.

Once you’ve found M2, you’re then free to experiment with a range of magnifications through the main eyepiece. It handles magnification well, just getting bigger and better as you pump up the power – in preparing this article, I viewed it at magnifications of 88, 125 and 250, and could have continued to up the ante were the appropriate eyepieces at hand (it was a beautiful night at the viewing pad constructed on the Winton Wetlands near Benalla, Victoria, with a clear dark sky, good seeing and no wind). This image, sourced from www.astroimages.de via Wikipedia approximates the view through my ‘scope at 250x.

That’s all we have for this month folks, ANS will return in December for another tour of the night sky.

As always, any questions, comments or suggestions are welcome and may be directed to: waynerobertsau@yahoo.com.au

Until next month:

CLEAR SKIES and HAPPY HUNTING