Category: Guide to Space

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The zodiacal constellation of Scorpius resides on the ecliptic plane and was one of the original 48 constellations charted by Ptolemy to be later adopted as a modern constellation by the IAU. It covers 497 square degrees of sky and ranks 33rd in size. Scorpius has 15 main stars in its asterism and 47 Bayer Flamsteed designated stars within its confines. It is bordered by the constellations of Sagittarius, Ophiuchus, Libra, Lupus, Norma, Ara and Corona Australis. Scorpius is visible to all observers located at latitudes between +40° and ?90° and is best seen at culmination during the month of July.

There are two annual meteor showers associated with the constellation of Scorpius. The first is the Alpha Scorpiids – which begin on or about April 16 and end around May 9. The peak date of most activity is on or about May 3 and the radiant is near the brilliant red star, Antares. The second meteor shower, the June Scorpiids peaks on or about June 5 of each year. The radiant for this particular meteor shower is closer to the Ophiuchus border and the activity rate on the peak date is high – with about 20 meteors (average) per hour and many reported fireballs.

Because Scorpius was easy visible to ancient civilizations and its patterns do resemble the Scorpion which it represents, there is a great deal of mythology associated with this constellation. To the Greeks it represented the creature sent by Hera to eliminate Orion the Hunter – forever kept apart in the sky to continue their heavenly feud. Perhaps it was Apollo who sent the Scorpion and Orion flees it? Scorpius was also said to appear to Phaethon, who wrecked the sun-chariot when the horses balked at the mighty monster’s appearance. The Oriental culture recognized this pattern of stars as part of the Dragon, while the Polynesians saw it as a fishhook. No matter what legend you choose to place on this pattern of stars, its curving asterism is very distinctive and easy to recognize!

Let’s begin our binocular tour of Scorpius with its brightest star – Alpha – the “a” symbol on our chart. Antares is part of of the Upper Scorpius Association of Stars and is no doubt also a star poised on the edge of extinction. At a safe distance of 500 light-years, you’ll find this pulsating red variable equally fascinating to the eye as well as to the telescope. Unlike other stars, Alpha Scorpii also has a companion which can be revealed to small telescopes under steady conditions. Discovered on April 13, 1819 during a lunar occultation, this 6.5 magnitude green companion isn’t the easiest to split from such a bright primary – but it’s certainly fun to try to spot its 5.4 magnitude green companion. Like winter’s Sirius, the Antares pair needs especially still – but not necessarily dark – skies. It also requires a well-chosen magnification – one high enough to separate the two close stars (2.9 arc seconds), but low enough to concentrate the fainter star’s (magnitude 5.4) light. Did you know that Antares’ true rival is brighter Betelgeuse? Photometric measurements show that more massive Betelgeuse is slightly redder than Antares. Fortunately, the “Rival” does reside along the ecliptic plane allowing us many opportunities to see it accompany other solar system objects and be occulted by the Moon!

Keep your binoculars handy because all you have to know is Antares and go west…

Just slightly more than a degree away you’ll find a major globular cluster perfectly suited for every size telescope and binoculars – M4 (RA 16 23 35 Dec 26 31 31). This 5th magnitude Class IX cluster can even be spotted unaided from a dark location! In 1746 Philippe Loys de Cheseaux happened upon this 7200 light-year distant beauty – one of the nearest to us. It was also included in Lacaille’s catalog as object I.9 and noted by Messier in 1764. Much to Charles’ credit, he was the first to resolve it!

As one of the loosest globular clusters, M4 would be tremendous if we were not looking at it through a heavy cloud of interstellar dust. To binoculars, it is easy to pick out a very round, diffuse patch – yet it will begin resolution with even a small telescope. Large telescopes will also easily see a central “bar” of stellar concentration across M4’s core region, which was first noted by William Herschel. As an object of scientific study, the first millisecond pulsar was discovered within M4 in 1987 – one which spins 10 times faster than the Crab Nebula pulsar. Photographed by the Hubble Space Telescope in 1995, M4 was found to contain white dwarf stars – the oldest in our galaxy – with a planet orbiting one of them! A little more than twice the size of Jupiter, this planet is believed to be as old as the cluster itself. At 13 billion years, it would be three times the age of the Sol system!

Keep your binoculars or a small telescope handy as well go off to explore a single small globular cluster – Messier 80. Located about 4 degrees northwest of Antares (half a fist), this little globular cluster is a powerpunch. Located in a region heavily obscured by dark dust, the M80 will shine like an unresolvable star to small binoculars and reveal itself to be one of the most heavily concentrated globulars to the telescope. Discovered within days of each other by Messier and Mechain respectively in 1781, this intense cluster is around 36,000 light years distant.

In 1860, the M80 became the first globular cluster to contain a nova. As stunned scientists watched, a centrally located star brightened to magnitude 7 over a period of days and became known as T Scorpii. The event then dimmed more rapidly than expected, making observers wonder exactly what they had seen. Since most globular clusters contain stars all of relatively the same age, the hypothesis was put forward that perhaps they had witnessed an actual collision of stellar members. Given the cluster contains more than a million stars, the probability remains that some 2700 collisions of this type may have occurred during the M80’s lifetime.

Now head for Lambda Scorpii and hop three fingerwidths northeast to NGC 6406 (RA 17 40 18 Dec -32 12 00)… We’re hunting the “Butterfly!” Easily seen in binoculars and tremendous in the telescope, this brilliant 4th magnitude open cluster was discovered by Hodierna before 1654 and independently found by de Cheseaux as his Object 1 before being cataloged by Messier as M6. Containing about 80 stars, the light you see tonight left its home in space around the year 473 AD. Messier 6 is believed to be around 95 million years old and contains a single yellow supergiant – the variable BM Scorpii. While most of M6’s stars are hot, blue, and belong to the main sequence, the unique shape of this cluster gives it not only visual appeal, but wonderful color contrast as well.

Less than 3 arc minutes east of 3.3 magnitude G Scorpii (the tail star of the Scorpion) is 7.4 magnitude globular cluster NGC 6441. No challenge here. This 38,000 light-year distant compact cluster is around 13 thousand light-years from the galactic core. It was first noted by James Dunlop from southeastern Australia in 1826.

Around two and a half degrees northeast of G Scorpii (and NGC 6441) is another interesting deep sky twosome – bright open cluster M7 and faint globular NGC 6453. M7 was first recorded as a glowing region of faint stars by Ptolemy circa 130 CE. Located 800 light-years away, the cluster includes more than half a dozen 6th magnitude stars easily resolved with the least amount of optical aid. Through telescopes, as many as 80 various stars can be seen and it rocks in binoculars!

Now head northeast and the faint haze of 31,000 light-year distant globular cluster NGC 6453 will reveal itself to mid- and large-sized scopes. Like NGC 6441, this globular cluster was discovered from the southern hemisphere, in this case by John Herschel on June 8, 1837 while observing from the Cape of Good Hope, South Africa.

It’s time to aim your telescope at NGC 6302, a very curious planetary nebula located around three fingerwidths west of Lambda Scorpii: it is better known as the “Bug” nebula (RA 17 13 44 Dec -37 06 16). With a rough visual magnitude of 9.5, the Bug belongs to the telescope – but it’s history as a very extreme planetary nebula belongs to us all. At its center is a 10th magnitude star, one of the hottest known. Appearing in the telescope as a small bowtie, or figure 8 shape, huge amounts of dust lie within it – very special dust. Early studies showed it to be composed of hydrocarbons, carbonates and iron. At one time, carbonates were believed associated with liquid water, and NGC 6302 is one of only two regions known to contain carbonates – perhaps in a crystalline form.

Ejected at a high speed in a bi-polar outflow, further research on the dust has shown the presence of calcite and dolomite, making scientists reconsider the kind of places where carbonates might form. The processes that formed the Bug may have begun 10,000 years ago – meaning it may now have stopped losing material. Hanging out about 4000 light-years from our own solar system, we’ll never see NGC 6302 as well as the Hubble Telescope presents its beauty, but that won’t stop you from enjoying one of the most fascinating of planetary nebulae!

Now begin your starhop at the colorful southern Zeta pair and head north less than one degree for NGC 6231 (RA 16 : 54.0 Dec -41 : 48). Wonderfully bright in binoculars and well resolved to the telescope, this tight open cluster was first discovered by Hodierna before 1654. De Cheseaux cataloged it as object 9, Lacaille as II.13, Dunlop as 499, Melotte as 153, and Collinder as 315. No matter what catalog number you chose to put in your notes, you’ll find the 3.2 million year young cluster shining as the “Northern Jewelbox!” For high power fans, look for the brightest star in this group – it’s van den Bos 1833, a splendid binary.

About another degree north is loose open cluster Collinder 316, with its stars scattered widely across the sky. Caught on its eastern edge is another cluster known as Trumpler 24, a site where new variables might be found. This entire region is encased in a faint emission nebula called IC 4628 – making this low power journey through southern Scorpius a red hot summer treat!

When you are done, hop west (RA 16 25 18 Dec 40 39 00) to encounter the fine open cluster NGC 6124. Discovered by Lacaille and known to him as object I.8, this 5th magnitude open cluster is also known as Dunlop 514, as well as Melotte 145 and Collinder 301. Situated about 19 light-years away, it will show as a fine, round, faint spray of stars to binoculars and be resolved into about 100 stellar members to larger telescopes. While NGC 6124 is on the low side for northern observers, it’s worth the wait for it to hit its best position. Be sure to mark your notes, because this delightful galactic cluster is a Caldwell object and a southern skies binocular reward!

There are many, many more splendid object to be discovered in the constellation of Scorpius, so be sure to get a detailed star chart and enjoy!

Sources:
Wikipedia
Chandra Observatory
Chart Courtesy of Your Sky.

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The zodiacal constellation of Sagittarius resides on the ecliptic plane and was one of the original 48 constellations charted by Ptolemy to be later adopted as a modern constellation by the IAU. It spans 867 square degrees of sky and ranks 15th in constellation size. It has 7 primary stars in its main asterism and 68 Bayer Flamsteed designation stars within its confines. Sagittarius is bordered by the constellations of Aquila, Scutum, Serpens Cauda, Ophiuchus, Scorpius. Corona Australis, Telescopium, Indus, Microscopium and Capricornus. It is visible to all observers located at latitudes between +55° and ?90° and is best seen at culmination during the month of August.

The easily recogniged “tea pot” shape of Sagittarius was well known in mythology as being represented by the half-man, half-horse – the Centaur. According to some legends, he was the offspring of of Philyra and Saturn. Named Chiron, he turned himself into a horse to hide from his jealous wife and was eventually immortalized in the stars. He is often depicted as an archer as well, with his arrow pointed directly at the red heart of the Scorpion – Antares. Sagittarius may represent the son of Pan, who invented archery and was sent to entertain the Muses who threw a laurel wreath at his feet. No matter what identity you choose, one thing is for certain – there’s no mistaking the presence of the nearby Sagittarius arm of the Milky Way!

(Since the constellation of Sagittarius is simply slopping over with deep sky objects, creating a small, workable chart here would be very confusing. For this reason, I have only chosen a few of my favorite objects to highlight and I hope you enjoy them, too!)

Let’s begin our binocular tour of Sagittarius with its alpha star – the “a” symbol on our map. Located far south in the constellation, Alpha Sagittarii is far from being the brightest of its stars and goes by the traditional name of Rukbat – the “knee of the Archer”. It’s nothing special. Just a typical blue, class AB dwarf star located about 170 light years from Earth, but it often gets ignored because of its position. Have a look at Beta while you’re there, too. It’s the “B” symbol on our map. That’s right! It’s a visual double star and its name is Arkab – the “hamstring”. Now, power up in a telescope. Arkab Prior is the westernmost and it truly is a binary star accompanied by a 7th magnitude dwarf star and seperated by about 28 arcseconds. It’s located about 378 light years from Earth. Now, hop east for Arkab Posterior. It is a spectral type F2 giant star, but much closer at 137 light years in distance.

Now turn your attention towards Epsilon Sagittarii – the backwards “3” symbol on our chart. Kaus Australis is actually the brightest star in the bottom righthand corner of the teapot and the brightest of all the stars in Sagittarius and the 36th brightest in the night sky. Hanging out in space some 134 light years from our solar system, this A-class giant star is much hotter than most of its main sequence peers and spinning over 70 times faster on its axis than our Sun. This rapid movement has caused a shell to form around the star, dimming its brightness… But not nearly as dim as its 14th magnitude companion! That’s right… Epsilon is a binary star. The disparate companion is well seperated at 32 arc seconds, but will require a larger telescope to pick away from its bright companion!

Ready for more? Then have a look at Gamma – the “Y” symbol on our map. Alnasl, the “arrowhead” is two star systems that share the same name. If you have sharp eyes, you can even split this visual double star without aid! However, take a look in the telescope… Gamma-1 Sagittarii is a Cepheid 1500 light year distant variable star in disguise. It drops by almost a full stellar magnitude in just a little under 8 days! Got a big telescope? Then take a closer look, because Gamma-1 also shows evidence of being a close binary star, as well has having two more distant 13th magnitude companions, W Sagittarii B, and C separated by 33 and 48 arcseconds respectively. How about Gamma-2? It’s just a regular type-K giant star – but it’s only 96 light years from Earth!

Located just slightly more than a fingerwidth above Gamma Sagittarii and 5500 light-years away, NGC 6520 (RA 18 03 24 Dec -27 53 00) is a galactic star cluster which formed millions of years ago. Its blue stars are far younger than our own Sun, and may very well have formed from what you don’t see nearby – a dark, molecular cloud. Filled with dust, Barnard 86 literally blocks the starlight coming from our galaxy’s own halo area in the direction of the core. To get a good idea of just how much light is blocked by B 86, take a look at the star SAO 180161 on the edge. Behind this obscuration lies the densest part of our Milky Way! This one is so dark that it’s often referred to as the “Ink Spot.” While both NGC 6520 and B 86 are about the same distance away, they don’t reside in the hub of our galaxy, but in the Sagittarius Spiral Arm. Seen in binoculars as a small area of compression, and delightfully resolved in a telescope, you’ll find this cluster is on the Herschel “400” list and many others as well.

Are you ready for a whirlwind tour of the Messier Catalog objects with binoculars or a small telescope? Then let’s start at the top with the “Nike Swoosh” of M17.
Easily viewed in binoculars of any size and outstanding in every telescope, the 5000 light-year distant Omega Nebula was discovered by Philippe Loys de Chéseaux in 1745-46 and later (1764) cataloged by Messier as object 17 (RA 18 20 26 Dec -16 10 36). This beautiful emission nebula is the product of hot gases excited by the radiation of newly born stars. As part of a vast region of interstellar matter, many of its embedded stars don’t show up in photographs, but reveal themselves beautifully to the eye at the telescope. As you look at its unique shape, you realize many of these areas are obscured by dark dust, and this same dust is often illuminated by the stars themselves. Often known as “The Swan,” M17 will appear as a huge, glowing check mark or ghostly “2” in the sky – but power up if you use a larger telescope and look for a long, bright streak across its northern edge with extensions to both the east and north. While the illuminating stars are truly hidden, you will see many glittering points in the structure itself and at least 35 of them are true members of this region, which spans up to 40 light-years and could form up to 800 solar masses. It is awesome…

Keeping moving south and you will see a very small collection of stars known as M18, and a bit more south will bring up a huge cloud of stars called M24. This patch of Milky Way “stuff” will show a wonderful open cluster – NGC 6603 – to average telescopes and some great Barnard darks to larger ones. M24 is often referred to as the “Small Sagittarius Star Cloud”. This vast region is easily seen unaided from a dark sky site and is a stellar profusion in binoculars. Telescopes will find an enclosed galactic cluster – NGC 6603 – on its northern border. For those of you who prefer a challenge, look for Barnard Dark Nebula, B92, just above the central portion.

Now we’re going to shift to the southeast just a touch and pick up the M25 open cluster. M25 is a scattered galactic cluster that contains a cephid variable – U Sagittarii. This one is a quick change artist, going from magnitude 6.3 to 7.1 in less than seven days. Keep an eye on it over the next few weeks by comparing it to the other cluster members. Variable stars are fun! Head due west about a fist’s width to capture the next open cluster – M23. From there, we are dropping south again and M21 will be your reward. Head back for your scope and remember your area, because the M20 “Triffid Nebula” is just a shade to the southwest. Small scopes will pick up on the little glowing ball, but anything from about 4″ up can see those dark dust lanes that make this nebula so special. The “Trifid” nebula appears initially as two widely spaced stars – one of which is a low power double – each caught in its own faint lobe of nebulosity. Keen eyed observers will find that the double star – HN 40 – is actually a superb triple star system of striking colors! The 7.6 magnitude primary appears blue. Southwest is a reddish 10.7 magnitude secondary while a third companion of magnitude 8.7 is northwest of the primary.

Described as “trifid” by William Herschel in 1784, this tri-lobed pattern of faint luminosity broken by a dark nebula – Barnard 85 – is associated with the southern triple. This region is more brightly illuminated due to the presence of the star cluster and is suffused with a brighter, redder reflection nebula of hydrogen gas. The northern part of the Trifid (surrounding the solitary star) is fainter and bluer. It shines by excitation and is composed primarily of doubly ionized oxygen gas. The entire area lies roughly 5000 light-years away. What makes M20 the “Trifid” nebula, are the series of dark, dissecting dust lanes meeting at the nebula’s east and west edges, while the southernmost dust lane ends in the brightest portion of the nebula. With much larger scopes, M20 shows differences in concentration in each of the lobes along with other embedded stars. It requires a dark night, but the Trifid is worth the hunt. On excellent nights of seeing, larger scopes will show the Trifid much as it appears in black and white photographs!

You can go back to the binoculars again, because the M8 “Lagoon Nebula” is south again and very easy to see. Easily located about three finger-widths above the tip of the teapot’s spout (Al Nasl), M8 is one of Sagittarius’ premier objects. This combination of emission/reflection and dark nebula only gets better as you add an open cluster. Spanning a half a degree of sky, this study is loaded with features. One of the most prominent is a curving dark channel dividing the area nearly in half. On its leading (western) side you will note two bright stars. The southernmost of this pair (9 Sagittarii) is thought to be the illuminating source of the nebula. On the trailing (eastern) side, is brightly scattered cluster NGC 6530 containing 18 erratically changing variables known as “flare stars.” For large scopes, and those with filters, look for small patches of dark nebulae called “globules.” These are thought to be “protostar” regions – areas where new stars undergo rapid formation. Return again to 9 Sagittarii and look carefully at a concentrated portion of the nebula west-southwest. This is known as the “Hourglass” and is a source of strong radio emission.

This particular star hop is very fun. If you have children who would like to see some of these riches, point out the primary stars and show them how it looks like a dot-to-dot “tea kettle.” From the kettle’s “spout” pours the “steam” of the Milky Way. If you start there, all you will need to do is follow the “steam” trail up the sky and you can see the majority of these with ease.

At the top of the “tea kettle” is Lambda. This is our marker for two easy binocular objects. The small M28 globular cluster is quite easily found just a breath to the north/northwest. The larger, brighter and quite wonderful globular cluster M22 is also very easily found to Lambda’s northeast. Ranking third amidst the 151 known globular clusters in total light, M22 is probably the nearest of these incredible systems to our Earth, with an approximate distance of 9,600 light-years. It is also one of the nearest globulars to the galactic plane. Since it resides less than a degree from the ecliptic, it often shares the same eyepiece field with a planet. At magnitude 6, the class VII M22 will begin to show individual stars to even modest instruments and will burst into stunning resolution for larger aperture. About a degree west-northwest, mid-sized telescopes and larger binoculars will capture the smaller 8th magnitude NGC 6642 (RA 18 31 54 Dec -23 28 34). At class V, this particular globular will show more concentration toward the core region than M22. Enjoy them both!

Now we’re roaming into “binocular possible” but better with the telescope objects. The southeastern corner of the “tea kettle” is Zeta, and we’re going to hop across the bottom to the west. Starting at Zeta, slide southwest to capture globular cluster M54. Keep heading another three degrees southwest and you will see the fuzzy ball of M70. Just around two degrees more to the west is another globular that looks like M70’s twin. The small globular M55 is out there in “No Man’s Land” about a fist’s width away east/south east of Zeta .

Ready for a big telescope challenge? Then try your hand at one the sky’s most curious galaxies – NGC 6822. This study is a telescopic challenge even for skilled observers. Set your sights roughly 2 degrees northeast of easy double 54 Sagittarii, and have a look at this distant dwarf galaxy bound to our own Milky Way by invisible gravitational attraction…

Named after its discoverer (E. E. Barnard – 1884), “Barnard’s Galaxy” is a not-so-nearby member of our local galaxy group. Discovered with a 6″ refractor, this 1.7 million light-year distant galaxy is not easily found, but can be seen with very dark sky conditions and at the lowest possible power. Due to large apparent size, and overall faintness (magnitude 9), low power is essential in larger telescopes to give a better sense of the galaxy’s frontier. Observers using large scopes will see faint regions of glowing gas (HII regions) and unresolved concentrations of bright stars. To distinguish them, try a nebula filter to enhance the HII and downplay the star fields. Barnard’s Galaxy appears like a very faint open cluster overlaid with a sheen of nebulosity, but the practiced eye using the above technique will clearly see that the “shine” behind the stars is extragalactic in nature.

Now look less than a degree north-northwest to turn up pale blue-green NGC 6818 – the “Little Gem” planetary. Easily found in any size scope, this bright and condensed nebula reveals its annular nature in larger scopes but hints at it in scopes as small as 6″. Use a super wide field long-focus eyepiece to frame them both!

Be sure to get a good star chart and enjoy the constellation of Sagittarius to its fullest potential – there’s lots more out there!

Sources:
SEDS
Chandra Observatory
Wikipedia
Chart Courtesy of Your Sky.

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Sagitta belongs to the original 48 constellations charted by Ptolemy and it remains one of the 88 modern constellations defined by the International Astronomical Union. Located north of the ecliptic plane, it spans 80 square degrees of sky, ranking 86th in constellation size. Sagitta contains 4 main stars in its asterism and has 19 Bayer Flamsteed designated stars within its confines. It is bordered by the constellations of Vulpecula, Hercules, Aquila and Delphinus. Sagitta is visible to all observers located at latitudes between +90° and ?70° and is best seen at culmination during the month of August.

In ancient history, the constellation of Sagitta was once known as Sham – a name applied today to its Alpha star. It was the Romans who named it Sagitta, the “Arrow”. In ancient Greek myth, it depicted the weapon which Hercules used to kill the eagle Aquila – or perhaps the Stymphalian birds. Perhaps it is Cupid’s Arrow, or the one which the Centaur shot at Chiron… No matter which tale you choose, it’s unmistakeable arrow shape was clear to all cultures, including the Persians, Hebrews, Greeks and Romans. Only Johann Bayer seemed to have trouble with it… For it is one of those constellation in which he named the bright stars out of order!

Let’s begin our binocular tour of Sagitta with Alpha – the “a” symbol on our chart. While Sham isn’t the brightest star in the constellation, this yellow bright giant star’s name really does mean “arrow”. Located about about 475 light years from Earth, it has a stellar luminosity 340 times that of the Sun and is about 20 times larger. Sham falls inside the “Hertzsprung Gap,” a perimeter of stellar temperature and luminosity that few stars fit inside. From its point in stellar evolution, it should have stopped fusing hydrogen to helium and began to brighten. However, that’s not the case. For some reason, Sham’s surface shows an abundance of nitrogen – a state which could only occur from interior helium fusion. A Cepheid variable star in the making? Perhaps!

Take a look at Beta in binoculars – the “B” symbol on our map. It’s G-type yellow star like our own Sun. Beta Sagittae is a giant star and, like Sham, is only about 467 light years away from our solar system. Delta, in the center of the arrow, is a spectroscopic binary star. It consists of a class M giant star and a quiet little hydrogen fusing dwarf star. Both are happy at a distance of about 448 light years from here and both happily separated from each other by a little less than 9 AU. Don’t forget red giant star, Gamma, either! The “Y” star on our chart might be 275 light years away, but it shines 640 times brighter than our Sun! It, too, is highly evolved…. Surrounded by a shell and well on its way to becoming a Mira-type variable star and eventually a white dwarf star about the size of the Earth.

For large binoculars and small telescopes, set your sights towards Messier 71 (RA 19 : 53.8 Dec +18 : 47). At around 8th magnitude, this loosely structured globular cluster is a challenge for smaller optics, but a wonderful study. It was originally discovered by Philippe Loys de Chéseaux in 1746 and included by Charles Messier in his Messier catalog of comet-like objects in 1780. Residing about 12,000 light years away and spanning about 27 light years across, there has long been a debate about this star cluster’s proper designation… globular cluster or concentrated galactic star cluster? Thanks to modern photometry, astronomers have detected a short “horizontal branch” in the H-R diagram of M71, which is characteristic of a globular cluster. Its low metallicity content has now been recognized as that of a “youthful” globular cluster and its lack of RR Lyrae variables places it at an age of between 9 and 10 billion years old.

For two challenging large telescope studies, let’s try your hand with planetary nebulae. The first is NGC 6879 (RA 20 : 10.5 Dec +16 : 55). At an apparent magnitude of 13, this challenging study will require high magnification and careful alignment to pick out from the stellar field. However, don’t be discouraged, because the nebula itself is rather bright and conspicuous as a “hairy star”. Just as challenging is NGC 6886 (RA 20 : 12.7 Dec +19 : 59). While the central star is a magnitude brighter at 12, you’re going to need at least an 8″ telescope to detect this one. It has an unusual chemical composition which an OIII filter helps to reveal.

Sources:
Wikipedia
Chandra Observatory
SEDS
Chart Courtesy of Your Sky.

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Located south of the ecliptic plane, the small, faint constellation of Reticulum was first named Rhombus by astronomical clock creator – Isaac Habrecht. It was later renamed Reticulum by Nicolas Louis de Lacaille in 1763. It spans 114 square degrees of sky, ranking 82nd in constellation size, has 4 main stars in its primary asterism and contains 11 Bayer Flamsteed designated stars within its confines. Reticulum is bordered by the constellations of Horologium, Dorado and Hydrus. It is visible to all observers located at latitudes between +23° and ?90° and is best seen at culmination during the month of January.

Since Reticulum is a “new” constellation, there is no mythology associated with it – only the story of how its name came to be. Originally named Rhombus by Isaac Habrecht, it was a name the fit the star pattern, considering a rhombus is a basic diamond pattern. Habrecht and his brother were talented Germany clock makers and one of their specialities was in fashioning astronomical clocks. As a matter of fact, they built the second astronomical clock in Strasbourg between 1571 and 1574. It was designed by mathematician Christian Herlin, and as well as the Habrecht brothers, had astronomer and musician David Wolckenstein to assist. This fantasy clock had a staircase, huge amounts of artwork, musical embellishments, but was best known for its complexity as an astronomical device. It had a calendar dial, the astrolabe, the indicators for planets and eclipses… and a celestial globe. When Lacaille made his sojourn to the Cape of Good Hope, his intent wasn’t to usurp Habrecht’s place in astronomical history – but to unify astronomical catalogs. In an attempt to honor instruments of science and his telescope for which he used to chart the southern skies, Lacaille named this trapezoidal collection of stars Reticulum, the Latin derivative for the reticule crosshairs on his spyglass which enabled him to accurately pinpoint star positions. The name Reticulum stuck and was later adopted as one of the 88 modern constellations by the International Astronomical Union.

Let’s begin our binocular tour of Reticulum with its brightest star – Alpha – the “a” symbol on our chart. Alpha Reticuli is a yellow G class giant star which is about 163 light years away from Earth. It shines about 237 times brighter than our Sun and is about 21 times larger. It will eventually end its life quietly as a white dwarf star. But, take out your telescope and have a closer look! You’ll find out that Alpha is also a binary star with a very disparate 12th magnitude companion star nearby. While the star hasn’t moved in the last 150 years, the pair does display the same proper motion.

Keep binoculars handy and hop west for Zeti Reticuli. This binary star system located about 39 light years away from our own solar system. The pair of twin suns are very much like our own in temperature and mass – yellow dwarf stars – but it’s there the similarities end. At one time, astronomers believed the Zeta pairing to be old galactic halo Population II subdwarf stars, but recent research indicates the may belong to the younger galactic disk population. This makes the twin Zetas far older than our Sun – in the neighborhood of 8 billion years old. And they aren’t moving along alone! The pair belongs to the Zeta Herculis Moving Star Group. Both stars share similar proper motions and distances – and despite being so widely spaced, they are a true binary star with an orbital period of an estimated million years!

While viewing Zeta, keep in mind all the legends behind this particular pair. In 1961, alien abductees – Barney and Betty Hill – were “taken” by citizens who imparted information to Betty that their home star was the Zeta system. After a map was constructed by an amateur astronomer and eventually debunked by Carl Sagan, then later sensationalized by Bob Lazar, the Zeta “planet” theory eventually went into hibernation for fear of media attention. On September 20, 1996 a tentative discovery of a “hot Jupiter” in the Zeta system was discovered and quickly retracted as being “pulsations” from the star… and while conditions are possible for Earth-like planets to exists around these twins suns, low solar metallicity makes their presence unlikely.

Before you give up planetary hopes, hop to Epsilon Reticuli – the backwards “3” symbol on our map. Now here’s a binary system located approximately 59 light-years away that really does have a confirmed planet! The primary star is an orange subgiant star, while the secondary star is a white dwarf star. As of 2000, an extrasolar planet has been confirmed to be orbiting the primary star in the system! It is roughly the size of Jupiter and it orbits around the star every 418 days. What’s more, there could possibly be an Earth-like trojan accompanying it!

For binoculars, keep a watch on R Reticuli – a Mira-type variable star. While it takes 278.3 days for it to go through it’s changes, they are very dramatic. You’ll find this incredible star begins by shining at respectable magnitude of 6.5 only to virtually turn telescopic at magnitude 14 during its minima. Now that’s variable!

For a small telescope and big binocular challenge, try your hand at NGC 1313 (RA 3 : 18.3 Dec -66 : 30). At magnitude 9 and more than 8 arc minutes in size, this starburst galaxy is often referred to as the “Topsy Turvy” because of its unusual supershell spiral galaxy structure. Located about 15 million light years away, large telescopes will pick out strange features, like spiral arms which are lopsided and its rotational axis is not at the center of the nuclear bar.

Now, have a go at NGC 1559 (RA 4 : 17.6 Dec -62 : 47). Although this barred spiral galaxy is over a magnitude fainter and about half the size of the last, you’ll still find it quite bright and rich in the telescope. Although it was originally thought to be a member of the Dorado Galaxy Group, this Seyfert Galaxy is all alone in space. NGC 1559 has massive spiral arms and strong star formation. It contains a small bar which is oriented nearly east-west and spans 40?. Its bar and galactic disc are the source of very strong radio emissions!

Our last galaxy is NGC 1543 (RA 4 : 12.8 Dec -57 : 44). Also about magnitude 10.5 and about 4 arc minutes in size, Dunlop 100 really is considered part of the Dorado Galaxy Group. Look for a very bright nucleus in this spiral galaxy, with a faint east to west extension!

Chart Courtesy of Your Sky.

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The constellation of Pyxis is located south of the ecliptic plane. At one time its stars were considered part of the ancient constellation of Argo Navis as the “mast” of the great ship. In later years, Argo Navis was split into three seperate constellations – Puppis, Vela and Carina – by Nicolas Louis de Lacaille. At the time he named the Pyxis group of stars Pyxis Nautica – the “Mariner’s Compass”. It was suggested by John Herschel the group of stars be named Malus, the “Mast”, but the suggestion was not followed. When the constellation was officially recognized and placed permanently by the IAU, the name was shortened to just Pyxis. It covers 221 square degrees of sky and ranks 65th in size. Pyxis contains 3 main stars in its asterism and has 10 Bayer Flamsteed designated stars within its confines. It is bordered by the constellations of Hydra, Puppis, Vela and Antlia. Pyxis is visible to all observers located at latitudes between +50° and ?90° and is best seen at culmination during the month of March.

As a section of the great ship Argo Navis, the mythology of Pyxis is the legend of the great sea and the adventures of Jason and the Argonauts. The great galley was built under the orders of the goddess Athene, where she then fitted a beam into the prow from the oracle of Zeus. On board was a crew of Greek heroes, including such notable mythological figures such as Hercules, Castor and Pollux. Of course, their journeys were legendary, and after having acquired the golden fleece they dedicated the ship to the sea god Poseidon, who immortalized it in the stars and the first of the ocean-going vessels. Due to it’s enormous size, early cartographers often had difficulty portraying it on star charts and its magical prow had disappeared. The mariner’s compass, the constellation of Pyxis, was also once considered a part of Argo Navis, too… But has also been divided away with time. Small wonder since the magnetic compass was virtually unknown to the ancient Greeks! However, we cannot default Lacaille for his love of scientific instruments and his wish to immortalize them in the stars. Where charts did not depict the mast, Lacaille figured it was anchored in a reef and called his new constellation “la Boussole” to represent a marine compass.

Let’s begin our binocular tour of Pyxis with its brightest star – Alpha – the “a” symbol on our map. Alpha Pyxidis is 850 light years away from Earth and appears quite dim because of interstellar dust. In reality, this hot, blue-white giant star is about 18,000 times brighter than our own Sun and about 8 times larger. Hiding inside a circumstellar shell, Alpha might very well be a Beta Cephi variable star!

For large binoculars and small telescopes, try your hand at open cluster and planetary nebula combination, NGC 2818 (RA 9 : 16.0 Dec -36 : 37). At magnitude 8 and 9 arc minutes in size, it will be a challenge for smaller optics, but a fun one! The planetary nebula is very unique due to its association with a Population I open star cluster. This means the cluster itself is overabundant in HII regions and studies have shown that it is associated with the cluster and not just a chance alignment. Large telescopes will pick up lobes in the planetary nebula structure and a faint green coloration, while the cluster structure is very open and scattered.

Another challenging galactic star cluster for binoculars and small telescopes is NGC 2627 (RA 8 : 37.3 Dec -29 : 57). At magnitude 8 and 11 arc minutes in size, it makes a slightly better presentation with more compression and stars. While it will only be a hazy patch in binoculars, larger telescopes can expect to resolve out around 40 or so stars in the rich field and pick out some color in this intermediate aged open wonderland!

How about a telescope challenge? Then try your hand at NGC 2613 (RA 8 : 33.4 Dec -22 : 58). This 10th magnitude spiral galaxy is surprisingly large, bright, and overlooked! Located about 60 million light years away from our solar system, this under-rated jewel is a case study in radial velocity dispersions and stellar kinematics. According to research, massive edge-on spiral galaxy NGC 2613 shows evidence of supershells which, if confirmed, would be among the largest known!

Sources:
Wikipedia
University of Wisconsin
Chart Courtesy of Your Sky.

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The constellation of Puppis once belonged to a much larger constellation known as Argo Navis – the mythological ship used by Jason and the Argonauts. Argo Navis was recognized as one of the original 48 constellations charted by Ptolemy, but was later subdivided in 1752 by Nicolas Louis de Lacaille into three sections and renamed into Carina (the keel of the ship), Puppis (the poop deck), and Vela (the sails). Because Bayer Flamsteed designations were already in use at the time, the designations were also split, with each constellation taking the Argo Navis designation with it – such as Alpha and Beta belonging to Carina – while Vela has Gamma and Delta. After officially being listed as one of the 88 modern constellation by the International Astronomical Union, Puppis now occupies 673 square degrees of sky and ranks 20th in constellation size from its position just south of the ecliptic plane. Puppis is bordered by the constellations of Monoceros, Pyxis, Vela, Carina, Pictor, Columba, Canis Major and Hydra It contains 76 Bayer Flamsteed stars within its confines and its primary asterism is composed of 9 main stars. Puppis is visible to all observers located at latitudes between +40° and ?90° and is best seen at culmination during the month of February.

There are three minor annual meteor showers associated with the constellation of Puppis. Beginning each year on about April 15 through April 28, you can watch for activity from the Pi Puppids, with the peak date of maximum activity on or about April 23. The meteoroid stream is very irregular and the fall rate is variable. The Zeta Puppids begin activity around November 2 and end around December 20th with a peak date of on or about November 13th. This is also a very weak meteoroid stream which produces no more than about 3 meteors per hour at maximum. The Puppid-Velid meteor shower begins around December 2 and lasts through December 16th with a peak date on or about December 12. While this is also an understudied meteor shower, it does have a slightly more productive rate at a maximum of 4 meteors per hour during peak activity. The radiant for this shower is very complex, so keep an eye out in the whole general area. It contains several substreams and may have several different times of maxima.

As a section of the great ship Argo Navis, the mythology of Puppis is the legend of the great sea and the adventures of Jason and the Argonauts. The great galley was built under the orders of the goddess Athene, where she then fitted a beam into the prow from the oracle of Zeus. On board was a crew of Greek heros, including such notable mythological figures such as Hercules, Castor and Pollux. Of course, their journeys were legendary, and after having acquired the golden fleece they dedicated the ship to the sea god Poseidon, who immortalized it in the stars and the first of the ocean-going vessels. Due to it’s enormous size, early cartographers often had difficulty portraying it on star charts and its magical prow had disappeared. The mariner’s compass, the constellation of Pyxis, was also once considered a part of Argo Navis, too… But has also been divided away with time. As for Puppis the Poop Deck? Actually, being on the roof of the stern cabin is a mighty fine place to be if you’re sailing amongst the stars….

Let’s begin our binocular tour of Puppis with a look at the bright star right in the middle – Zeta. Named Naos, which means “ship”, this grand spectral class is O5Ia star is one of the hottest known that is visible to the unaided eye. Punching in with a surface temperature of 42,400 K, what you are looking at is an extreme blue supergiant star – one of the brightest stars in the Milky Way Galaxy! At a distance of about 1400 light years from Earth, it doesn’t appear to be that impressive, but if it were as close as Sirius, it would light up our nights bright enough to cause shadows! Putting of 21,000 times more visible light and 790,000 times more light across the spectrum than our own Sun, this incredible star would absolutely vaporize our Earth if it were anywhere near our solar system. In several hundred thousand years, Naos will begin to cool and eventually become a red supergiant star. When it ends its life in a couple of million years, chances are it will go hypernova – forming a black hole and eventually a new nebula for starbirth in the never-ending cycle of cosmic wonder. What causes it to be so unusual? There’s evidence that Noas is a “runaway star”… once formed in the Vela region and now 400 light years away from the womb.

Now, let’s begin in the north with binoculars for a look at open cluster Melotte 71 (RA 07:37:30 Dec -12:03:06). This outer disc cluster is also known as Tombaugh 2 and will show as a compression of stars in binoculars and reveal about 80 or so members to mid-sized telescopes at low magnification. It is fairly rich and contains several reddish stars.

Keep your binoculars handy, or stick with the scope for Messier 46 (RA 07: 41.8 Dec ?14:49). This grand galactic star cluster was discovered by Charles Messier in 1771. Located about 5500 light years away from Earth, you’ll find about 150 stars spread over a 30 light year wide area… But one will stand out from the rest. Good reason – it’s a planetary nebula! Planetary nebula NGC 2438 will appear at the cluster’s northern edge and is probably just in the line of sight since it does not share the same velocity as M46.

Do you see other open cluster nearby? That’s Messier 47 (RA 07:36.6 Dec -14:30). It was discovered by Giovanni Batista Hodierna before 1654 and independently discovered by Charles Messier on February 19, 1771 and added to the Messier Catalog. While it contains only about 50 or so stars, it’s much brighter and more well resolved in smaller optics. Not bad for being 78 million years old!!

Stick to the telescope to discover NGC 2440 (RA 07:41: 54.91 Dec -18:12:29.7). This planetary nebula has a central star with an exceptionally high surface temperature of 200,000 kelvins. Studied by the Hubble Space Telescope for its strange bow shape, NGC 2440 has a complex structure with dense ridges of material swept back from the nebula’s central star.

Take your telescopes or binoculars out and look just north of Xi Puppis (RA 07 44 36 Dec -23 52 00) for a “mass concentration” of starlight known as Messier 93. Discovered in March of 1781 by Charles Messier, this bright open cluster is a rich concentration of various magnitudes which will simply explode in sprays of stellar fireworks in the eyepiece of a large telescope. Spanning 18 to 22 light-years of space and residing more than 3400 light-years away, it contains not only blue giants, but lovely golds as well. Jewels in the dark sky! As you view this open star cluster, seize the moment to remember Messier, because this is one of the last objects he discovered personally. He described it as “A cluster of small stars without nebulosity” – but did he realize the light he was viewing at the time left the cluster during the reign of Ramses III? Ah, yes…sweet time. Did Charles have a clue this cluster of stars was 100 million years old? Or realize it was forming about the time Earth’s land masses were breaking up, dinosaurs ruled, and the first mammals and birds were evolving? Although H. G. Wells “Time Machine” is a work of fiction, each time we view through a telescope we take a journey back across time itself. Enjoy the mystery!

Now, head off for NGC 2669 (RA 8 : 44.9 Dec -52 : 58). At magnitude 6, this 12 arc minute open cluster is a dazzling little gem that is on many southern sky observing lists… one that’s a study for proper motions! More? Then try Collinder 135. It is also a bright and dazzling open cluster that contains Pi Puppis and may have once been part of an OB cluster. Pick Pi out of the group… with a mass of between 13 and 14 solar masses, it will most likely explode in it’s future taking its binary star companion with it! Oddly enough, Collinder 135 wasn’t even recognized as an open star cluster until the Hipparchos satellite revealed that all the stars there were at a similar distance!

Are you ready for a globular cluster? Then try NGC 2298 (RA 6 : 49.0 Dec -36 : 00). At around magnitude 9 and 7 arc minutes in size this one will be a challenge for smaller optics. NGC 2298 was discovered by James Dunlop on May 30, 1826 and cataloged as Dunlop 578. It contains a lot of variable stars and it is on its way to disruption. According to Hubble Space Telescope studies, it’s losing mass.

For the big telescope, try your luck with NGC 2427 (RA 7 : 36.5 Dec -47 : 38). At around 11th magnitude and about 7 arc minutes in size, this super low surface brightness spiral galaxy won’t take to any kind of magnification, so use a low power eyepiece. Studies have shown it displays peculiar velocities in it’s HII regions and may display gravitation instability.

Don’t forget, Puppis is located right in the Milky Way, so there’s plenty more deep sky objects to go! Get yourself a good star map and explore…

Sources:
SEDS
Wikipedia
Chart courtesy of Your Sky.

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Located just south of the ecliptic plane, Piscis Austrinus was one of the original 48 constellations charted by Ptolemy, and it remains one of the 88 modern constellations adopted by the IAU. Spanning 245 square degrees of sky, it ranks 60th in size. Piscis Austrinus contains 7 mains stars in its asterism and has 21 Bayer Flamsteed designated stars within its confines. It is bordered by the constellations of Capricornus, Microscopium, Grus, Sculptor and Aquarius. Piscis Austrinus can be seen by all observers located at latitudes between +55° and ?90° and is best seen at culmination during the month of October.

Piscis Austrinus is also known as Piscis Australis – Latin for the “Southern Fish”. Prior to the 20th century, it was also known as Piscis Notius. In mythology it is said to represent the parent of Pisces. Perhaps the legend came from the Syrians who did not eat fish, but worshipped them as gods. The Greeks also kept fish ponds at their temples and one legend tells of woman who was turned into a mermaid when she threw herself into a pond in a suicide attempt. There are those who believe Pisces Austrinus is associated with the Assyrian fish god Dagon and the Babylonian god Oannes, but at least all accounts give a rather “fishy” tale!

Let’s begin our binocular tour of Piscis Austrinus with its brightest star – Alpha – the “a” symbol on our map. Alpha Piscis Austrini is best known as Formalhaut – the “Mouth of the Whale”. This class-A main sequence star is about 25 light years from Earth, and like Vega, has an excess of infra-red radiation which indicated a circumstellar disk. Not only does it have a disk, but it has an extrasolar planet, too… One that was photographed by the Hubble Space Telescope between 2004 and 2006 and confirmed in 2008! The Jupiter-sized planet orbits about 11 billion miles away from the parent star and takes about 872 years to make the full trip – and may very well have a ring system which dwarf’s that of Saturn’s.

As stars go, Formalhaut is quite interesting enough on its own. In ancient times it was considered one of the four “royal” stars that marked the cardinal directions and Ptolemy gave it astrological significance as well. It is a young star, maybe around 100 to 300 million years old and part of the Castor Group of Moving Stars. The stellar association in the Castor group include stars of similar age, origin and similar velocity and include Castor, Fomalhaut, Vega, Alpha Cephei and Alphae Librae. All of these stars may have originated from the same location at some point in time which may have made them part of star cluster. In binoculars you will also notice another nearby star – TW Piscis Austrini – it is also a member of this group and may actually be a physical companion of Formalhaut. Keep a watch on TW, though! Because as its two letter designation indicates, it is a variable star… But not just any variable. TW Piscis Austrini is a flare star! While flares can erupt periodically within a matter of hours or days with no predictable timetable, TW is also a prime candidate for harboring an Earth-like habitable zone, too!

Are you ready to take out your telescope and conquer a few nice binary stars? Then have a look at Beta, Delta, Gamma and Eta! Both Beta, Delta and Gamma are widely separated, but disparate… While Eta is a more difficult split and more closely matched in magnitude. For a visual double star in binoculars, have a look at Upsilon… While the two aren’t physically related, they still make a pretty appearance in small optics!

For a big telescope challenge, let’s take on NGC 7314 (RA 22 : 35.8 Dec -26 : 03). At close to magnitude 11, this larger than 4 arc second barred spiral galaxy will really capture your attention. Why? Because it’s a Seyfert Galaxy! Containing an active galactic nucleus and home to starburst activity, NGC 7314 will present a bright, star-like core region surrounded by wispy arms in the eyepiece.

Or, try your luck with NGC 7221 (RA 22 : 11.3 Dec -30 : 37). At magnitude 12, this very faint and small spiral galaxy is going to be a challenge even for a large telescope. Stick with low magnification, because low surface brightness makes this particular galaxy more difficult to see.

Are you ready for a galaxy grouping? Then start with NGC 7172 (RA 22 : 02.0 Dec -31 : 52). At magnitude 12, this very small irregular galaxy is the brightest of the group, but details will be difficult to distinguish. Just south you will notice smaller and fainter elliptical galaxies NGC7176 and NGC 7174, too. While this Hickson Compact Group is a difficult visual study, it makes for a great astrophotography target! NGC 7172 is also a Seyfert Galaxy which is riddled from galaxy interaction with its neighbors and was extensively studied by Chandra in 2007 for its “hidden” properties!

Sources:
Chandra Observatory
Wikipedia
Chart courtesy of Your Sky.

Billions of years from now, the Milky Way will look totally different, as pictured to the left. When you look up at the sky, you may see another entire galaxy passing through the plane of our own, creating stars and supernovae and changing the entire sky.

Though most galaxies are rushing away from us as the Universe expands, Andromeda and the Milky Way are orbiting each other and closing in fast. Collisions between galaxies aren’t always catastrophic (the Milky Way is colliding with the Canis Major Dwarf galaxy right now, swallowing its stars up into the galactic disk), but they can trigger star formation on large scales and increase the number of supernovae.

When the galaxies collide, there is little chance that many stars will slam into each other directly because they are so spread out; however, the gas that lies between the stars can collide, heat up and trigger the formation of new stars. This interstellar gas and dust could also get sucked up by existing stars, increasing their mass to the point where they go supernova.

By the time the Milky Way and Andromeda collide, though, much of the gas in both galaxies will have been used up to create stars, so a “starburst” won’t happen. It won’t be a quick merger, though, and the spiral structure of each will be seriously changed. As you can see in this animated simulation from University of Toronto astronomer John Dubinski, the galaxies will pass through each other a few times, and the gravitational disturbance of this passage will throw stars willy-nilly into empty space.

Andromeda and the Milky Way will pass through each other once, then fall apart for about a billion years, then pass again, and again until finally settling down to merge completely about 5 billion years from now. The resulting galaxy won’t look anything like either of the merged galaxies – it will be a fuzzy blob called an elliptical galaxy. “Milkomeda” has a nice ring to it, and is one proposed name for the new merged galaxy.

When the galaxies do finally merge, there is a small chance that the Solar System will either join the Andromeda galaxy for a short while during one of the passes, or that it will be flung out of our galactic disk into interstellar space. For an in-depth analysis of this collision and statistics on the chances of the Sun and planets being ejected, check out “The Collision Between The Milky Way and Andromeda”  by Harvard-Smithsonian astrophysicists T.J. Cox and Abraham Loeb.

Of course, Andromeda is not the only thing that could collide with the Milky Way. There is currently a large cloud of hydrogen gas on a collision course with the Milky Way and though the edge of the cloud is already interacting with our galaxy, it won’t set off star-forming fireworks until at least 40 million years from now. Named Smith’s Cloud after the astronomer who discovered it in 1963, it is 11,000 light-years long and 2,500 light-years wide, and has enough hydrogen to form a million stars the mass of the Sun. More information about this collision can be found right here on Universe Today, and from the National Radio Astronomy Observatory.

Pamela and Fraser talk about what the Milky Way and Andromeda collision will look like in the September 28th, 2008 episode of Astronomy Cast, and the Milky Way in Episode 99.

Source: NASA

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Located on the ecliptic plane, Pisces is a constellation of the zodiac and one of the 48 original constellations listed by Ptolemy. Spanning approximately 889 square degrees of sky, Pisces ranks 14th in constellation size, despite its faint stars. It contains 21 main stars in its asterism and has 86 Bayer Flamsteed designated stars within its confines. Pisces is bordered by the constellations of Triangulum, Andromeda, Pegasus, Aquarius, Cetus and Aries. It can be seen by all observers located at latitudes between +90° and ?65° and is best seen at culmination during the month of February.

There is one annual meteor shower associated with Pisces which peaks on or about October 7 of each year. The Piscid meteor shower has a radiant near the Aries constellation and produces an average of 15 meteors per hour which have been clocked at speeds of up to 28 kilometers per second. As always, the meteoroid stream can begin a few days earlier and end a few days later than the expected peak and success on viewing depends on dark sky conditions.

In mythology, the constellation of Pisces is represented by two fish bound together with a piece of string. According to one Greek myth, Pisces represents the fish into which Aphrodite and her son Eros transformed in order to escape the monstrous Typhon; they are tied together with a cord on their tails, to make sure they do not lose one another! Even more mythology states that Pan changed himself into a goat-fish (Capricorn) and jumped into the river to save them… Or perhaps it was a pair of fish which rescued them from the reeds along the river banks… Or maybe they were turned into eggs that were saved by the fish… One thing is for certain, somewhere along the line, the translation got lost – but the twin fish got left in the sky!

Let’s begin our tour of Pisces with binoculars as we take a look at it’s Alpha star – the “a” symbol on our map. Crowned with the traditional name of Alrischa – “Knot In The Rope” – 139 light year distant Alpha Piscium surely isn’t the brightest in the sky, nor the easiest to find. However, once located, take the time to power up in a telescope because Alrischa is a close binary star with angular separation of presently 1.8″ between the components. While the secondary star is separated from the primary by about one stellar magnitude, take note of their soft color. Both are A type stars, but many observers have reported seeing them as white and pale blue. What’s more, each of the chemically peculiar components might also be spectroscopic binary stars, too!

Now, let’s take a look at Beta Piscium in binoculars – the “B” symbol on our map. Located 495 light years from Earth, Samakah, the “Fish’s Mouth”, is a B-class hydrogen fusing dwarf star. It produces 750 times more light than our own Sun and rotates fully on its axis in about 2 days. At 60 million years old, one day Samakah will become a giant star, losing 80% of its mass in its high velocity solar winds and eventually become a white dwarf star.

Time to have a look at the brightest star – Eta – the “n” symbol. This unusual, bright class B star is located 294 years away from our solar system and has the unique distinction of being one of the few of its class to have had its angular diameter measured. It is about 26 times larger than Sol and shines almost 316 times brighter! However, Eta is a dying star… reduced to internal helium fusion. If you power up in a telescope, perhaps you’ll catch a glimpse of this binary star’s small, disparate companion located about a second of arc away.

Now aim binoculars towards Gamma – the “Y” symbol on our chart. Gamma is a yellow-orange giant star located about 130 light years distant. Oddly enough for a giant, it only puts out about 61 times more light than our Sun – but with good reason… it’s currently fusing it’s core to carbon. Right now, it is waiting to become a white dwarf, but that’s not what distinguishes Gamma – it is its speed. Apparently Gamma came from outside our Milky Way Galaxy altogether! According to its low metal content and cyanogen-weak spectral signature, Gamma had to have originated outside the galactic disc and it is still traversing the sky at over three-quarters of a second of arc per year!

For a very nice optical double star in binoculars, take a look at Kappa – the “K” symbol… or better yet, turn a telescope towards TX Piscium. It’s a gorgeous carbon variable star, which shines a deep, ruby red and varies by about a magnitude with time.

Now, let’s talk some deep sky and a Messier catalog object. Located about about 1/2 degree North and 1 1/2 degree East of Eta Piscium (RA 01 : 36.7 Dec +15 : 47), grand design spiral galaxy, Messier 74 isn’t always an easy object for small telescopes and will require dark skies and good viewing conditions to be seen in binoculars. Discovered 1780 by Pierre Méchain, and later cataloged by Charles Messier, this 95,000 light year distant island of light is about the same size as our Milky Way galaxy. When viewing M74 is smaller optics, be sure to look for a very precise, almost stellar nucleus and faded, wispy spiral galaxy structure.

For a big telescope challenge, try your luck with NGC 676 (RA 01h 48m 57.3s Dec +05° 54′ 25.8″). It is also a spiral galaxy with a bright, sharp nucleus, but seen more edge on. At magnitude 11 and about 4 arc minutes in size, it isn’t going to be easy – but what challenge is?

Perhaps you’d like to try NGC 474 (RA 1 : 20.1 Dec +03 : 25), too. It’s a huge elliptical galaxy with tidally disrupted tails from galaxy interactions with nearby NGC 470. While NGC 474 is billed at magnitude 11, you’ll find its stellar bright nucleus so distracting that magnitude 12 NGC 470 will at first appear to be the brighter of the two. While averting your vision, see if you can catch magnitude 13 NGC 467 to the north as well. It is by far the smallest of this galaxy group!

As a curious note, the Vernal Equinox is currently located in Pisces and, due to the precession of the equinoxes, is slowly drifting below the western fish towards Aquarius. In astronomy, equinox is a moment in time at which the vernal point, celestial equator, and other such elements are taken to be used in the definition of a celestial coordinate system. The position at other equinoxes can be computed by taking into account precession, nutation and aberration, which directly affect e.g. right ascension and declination.

Sources:
SEDS
Chandra Observatory
Chart courtesy of Your Sky.