Author: Tammy Plotner

Positioned north of the ecliptic plane, the constellation of Perseus was one of the original 48 constellations listed by Ptolemy, and endures as one of the 88 modern constellations.adopted by the IAU. It covers 615 square degrees of sky and ranks 24th in constellation size. Perseus contains between 6 and 22 stars in its primary asterism and houses 65 Bayer Flamsteed designated stars within its confines. It is bordered by the constellations of Cassiopeia, Andromeda, Triangulum, Aries, Taurus, Auriga and Camelopardalis. Perseus is visible to all observers located at latitudes between +90° and ?35° and is best seen at culmination during the month of December.

There is one annual meteor shower associated with Perseus and it is one of the most reliable of all – the Perseids. The peak date occurs on or about August 10th of each year and the radiant – or point or origin is near the Double Cluster. The meteoroid stream duration for this meteor shower lasts about five days, with activity beginning one to two days prior to the peak date and ending two or three days afterwards. The Perseid meteor shower has a wonderful and somewhat grisly history. Often referred to as the “Tears of St. Lawrence” this annual shower coincidentally occurs roughly about the same date as the saint’s death is commemorated on August 10. While scientifically we know the appearance of the shooting stars are the by-products of comet Swift-Tuttle, our somewhat more superstitious ancestors viewed them as the tears of a martyred man who was burned for his beliefs. Who couldn’t appreciate a fellow who had the candor to quip “I am already roasted on one side and, if thou wouldst have me well-cooked, it is time to turn me on the other.” while being roasted alive? If nothing else but save for that very quote, I’ll tip a wave to St. Lawrence at the sight of a Perseid! While the fall rate – the number of meteors seen per hour – of the Perseids has declined in recent years since Swift-Tuttle’s 1992 return, the time to begin your Perseid watch is before the peak date of August 12. If you are contending with a Moon which will interfere with fainter meteors, the later you can wait to observe, the better. The general direction to face will be east around midnight and the activity will move overhead as the night continues. While waiting for midnight or later to begin isn’t a pleasant prospect, by then the Moon has gone far west and we are looking more nearly face-on into the direction of the Earth’s motion as it orbits the Sun, and the radiant – the constellation of the meteor shower origin – is also showing well. For those of you who prefer not to stay up late? Try getting up early instead! How many can you expect to see? A very average and cautiously stated fall rate for this year’s Perseids would be about 30 meteors per hour, but remember – this is a collective estimate. It doesn’t mean that you’ll see one every two minutes, but rather you may see four or five in quick succession with a long period of inactivity in between. You can make your observing sessions far more pleasant by planning for inactive times in advance. Bring a radio along, a thermos of your favorite beverage, and a comfortable place to observe from. The further you can get away from city lights, the better your chances will be.

The long “Y” shape of Perseus has a long and colorful mythological history. Perseus was conceived in a golden rain and he and his mother were cast into the sea in a chest – left to die. His mother prayed to Zeus for deliverance and they were rescued by a fisherman who raised Perseus as his son. Eventually the king, in trying to rid himself of Perseus, demanded horses as a wedding present. Knowing Perseus had none, he chose the head if Medusa instead. With the aid of the gods, Perseus defeated Medusa – and from her body sprang Pegasus, the winged horse. As the story goes, he then to flight to the lands of king Cepheus, where he then continued his saga with Cassiopeia and Andromeda – rescuing the maiden from the Cetus, the sea monster. This is why, according to legend, you find all of these constellations so close together in the sky… and Perseus is depicted holding the head of Medusa, whose most famous star – Algol – represents the eye of the demon.

Let’s begin our binocular tour with a look a the “Demon Star” – Beta Persei – the “B” symbol on our map. Beta Persei (RA 03 08 10 Dec +40 57 20) and it is the most famous of all eclipsing variable stars. Ancient history has given this star many names. Associated with the mythological figure Perseus, Beta was considered to be the head of Medusa the Gorgon, and was known to the Hebrews as Rosh ha Satan or “Satan’s Head.” Seventeenth century maps labeled Beta as Caput Larvae, or the “Specter’s Head,” but it is from the Arabic culture that the star was formally named. They knew it as Al Ra’s al Ghul, or the “Demon’s Head,” and we now know it as Algol. Because these medieval astronomers and astrologers associated Algol with danger and misfortune, we are led to believe that Beta’s strange visual variable properties had been noted throughout history. Italian astronomer Geminiano Montanari was the first to record that Algol occasionally “faded,” and its regular timing was cataloged in 1782 by John Goodricke, who surmised that it was being partially eclipsed by a dark companion orbiting it. Thus was born the theory of the eclipsing binary, which was proved spectroscopically for Algol in 1889 by H. C. Vogel. Located 93 light-years away from Earth, Algol is the nearest eclipsing binary, and is treasured by the amateur astronomer because it requires no special equipment to easily follow its stages. Normally Beta Persei holds a magnitude of 2.1, but approximately every three days it dims to magnitude 3.4 and gradually brightens again. The entire eclipse only lasts about 10 hours! Although Algol is known to have two additional spectroscopic companions, the true beauty of watching this variable star is not telescopic – but visual.

Now, let’s use our binoculars and head for Alpha Persei – the “a” symbol on our map. The brightest star of this constellation is also called Mirfak . It is a supergiant star of stellar spectral type F5 Ib with an apparent brightness of 1.79 magnitude and resides at a distance of about 590 light-years. Is it big? You bet. Mirfak is about 62 times larger than our Sun and shines 5000 times brighter, but the beauty is in the field. If you’ve noticed that Alpha is in a group of stars, you’ve noticed right. It’s called the Alpha Persei Association. Viewable with the unaided eye, but best in binoculars, this young, moving star cluster is also known as Melotte 20 or Collinder 39 and is around 601 light years away. Brightest members include Alpha, Delta, Epsilon, Psi, 29, 30, 34 and 48 Persei.

Keep your binoculars handy as we head off to NGC 869 and NGC 884 – the “Double Cluster”. These two open stars clusters (NGC 869 (RA 02:19.1 Dec +57:09) and NGC 884 (RA 02:22:0 Dec +57:08) are perhaps the most beautiful objects of the night sky for binoculars and small, rich field telescopes. Both lie at distances of more than 7,000 light years and are separated by several hundred light-years. Often seen by the unaided eye as a hazy patch in the winter Milky Way, the clusters were first recorded by Hipparchus, but have likely been known since antiquity. NGC 869 is considered to be as much as 19 million years old and this OB1 association sometimes is called Chi Persei. Its companion, NGC 884 is nearer to 12 million years old and is dominated by bright blue stars which notes its youth. Also look for a smattering of orange stars in larger telescopes!

Ready to get Messier? Then locate Messier 34 (RA 02:42:1 Dec +42:46). In binoculars, M34 will show around a dozen fainter stars clustered together, and perhaps a dozen more scattered around the field. Small telescopes at low power will appreciate M34 for its resolvability and the distinctive orange star in the center. Larger aperture scopes will need to stay at lowest power to appreciate the 18 light-year span of this 100 million year old cluster, but take the time to power up and study. You will find many challenging doubles inside!

Now hop on to NGC 1342 (RA 3:31.6 Dec +37:20). Holding a respectable magnitude 7 and covering about 14 arc minutes of sky, this small, compressed, open cluster of stars is well within binocular and small telescope range. It’s been studied for galactic disc metallicity and is on many binocular and deep sky observing lists.

How about two more galactic star clusters? Then try your hand at NGC 1545 (RA 4:20:9 Dec +50:15). It’s around 6th magnitude, but at 18 arc minutes in size will require at least a small telescope to separate it from the starry background. It has been studied for universality of initial mass function of open star clusters. More northern NGC 1528 (RA 4:15:4 Dec +51:14) is about the same magnitude, but a little larger and is also known as Herschel 61, Collinder 47 and Melotte 23.

What about NGC 1499? NGC 1499 (RA 04:00:07 Dec +36:37) is the “California Nebula”. If you’re able to view under very dark skies, the California Nebula can be seen unaided and in binoculars, but its low surface brightness makes it tough for a telescope. NGC 1499 is probably illuminated by Xi Persei, a hot blue-white main sequence star of spectral type O7e. This star belongs to an association of young stars which probably arose from this interstellar cloud, the Perseus OB2 association. What a great opportunity for astrophotographers!

You can also try IC 348 (RA 3:44.5 Dec +32:17). This open star cluster with nebulosity has an apparent magnitude of 7 – but that doesn’t mean it’s bright or easy. It’s a very faint reflection nebula that’s going to require perfect conditions and probably the aid of a nebula filter, too. The “Flying Ghost” has been the subject of many studies, including the search for outflows and protostars. In 2006, the Spitzer Space Telescope turned an eye its way to find disc-less T-Tauri type stars as well as thosel as surrounded by thick, primordial disks. Why is that important? “The disk longevity and thus conditions for planet formation appear to be most favorable for the K6-M2 stars, which are objects of comparable mass to the Sun for the age of this cluster.”

There are many other wonderful deep sky objects in Perseus, so get a good star chart and enjoy the “Hero”!

Sources:
Chandra Observatory
Wikipedia
Chart Courtesy of Your Sky.

Positioned north of the ecliptic plane, the constellation of Pegasus was one of the original 48 constellations listed by Ptolemy, and endures as one of the 88 modern constellations.adopted by the IAU. It covers 1121 square degrees of sky and ranks 11th in size. Pegasus contains between 9 and 17 main stars in its asterism (depending on how you depict it) and has 88 Bayer Flamsteed designated stars within its confines. Pegasus is bordered by the constellations of Andromeda, Lacerta, Cygnus, Vulpecula, Delphinus, Equuleus, Aquarius and Pisces. It is visible to observers located at latitudes between +90° and ?60° and is best seen at culmination during the month of October.

There is one annual meteor shower associated with the constellation of Pegasus which peaks on or about November 12 of each year – the Pegasids. The radiant – or point of origin – for the meteor shower is near the asterism of the “Great Square”. Activity begins around October 10 and lasts to late November. The average fall rate at maximum during the peak is 10 per hour. This particular meteor used to be spectacular, but Jupiter has perturbed the meteor stream over the years and lessened the activity.

In mythology, Pegasus represents the Winged Horse, and child of Medusa who was slain by the hero Perseus. According to Greek mythology, Pegasus was delivered to Mount Helicon by Bellerophon, where the magnificent horse kicked the source of poetic inspiration – the Spring of Hippocrene – into flowing. When Bellerophon defeated Chimaera, he became so proud he ordered Pegasus to fly him to Mount Olympus. This action angered Zeus, who ordered an insect to sting Pegasus, resulting in Bellerophon’s fatal fall to Earth. Zeus then went on to recognize Pegasus in the stars as the “Thundering Horse of Jove” – carrier of his lightning bolts.

Let’s begin our binocular tour of Pegasus with its brightest star – Alpha – the “a” symbol on our map. Alpha Pegasi’s proper name is Markab and it marks the southwestern corner of the asterism of the Great Square. Located 140 light years from Earth, Markab is a hot class B (B9) dwarf star which shines about 205 times brighter than our own Sun and is about three times larger. This fast rotator completes a full turn on its axis in just about 36 hours! Right now, Markab sits on the edge of the main sequence, about to die and become a much cooler orange giant star. It’s about as “normal” as a star can be!

Now, turn your binoculars towards Beta – the “B” symbol. Named Scheat, you’ll find this particular star located in the northwestern corner of the Great Square and about 200 light years from our solar system. Scheat is unusual among bright stars in having a relatively cool surface temperature of 3700 degrees Kelvin, compared to stars such as our Sun. Scheat is a red giant star some 95 times larger than Sol and has a total stellar luminosity of 1500 times solar. It is also an irregular variable star, its brightness changing from magnitude 2.31 to 2.74.

You’ll need a telescope to reveal the mysteries surrounding Eta Pegasi – the “n” symbol on our map. Named Matar and located about 215 light years away, this spectral class G2II-III star has a close binary star companion of class F0V. There are also 2 class G stars further away that may or may not be physically related to the main pair. According to Jim Kaler, “Matar is double star and may well be quadruple, consisting of a very unequal pair of pairs, an unbalanced double-double. The brighter of the bright pair is on its way to becoming a much larger giant, and will eventually expand to a radius of a quarter the distance that now separates the two stars, streams of matter running from the brighter to the dimmer creating quite a sight from the smaller pair. Eventually the bright star of the brighter pair will fade to become a white dwarf, this double perhaps looking something like Sirius does today.”

Next up? Epsilon Pegasi – the backwards “3” symbol on our map. Located 670 light years away, Enif is a cool star for more than one reason! To begin with, Enif is orange class K (K2) supergiant star whose stellar temperature only averages about 4460 degrees Kelvin. Even in binoculars you’ll notice the reddish hue. It’s big, too… About 150 times the size of our Sun and if located in our solar system would fill out the space about halfway to the orbit of Venus. This supergiant star’s fate awaits it as a supernova, but there is always a possibility it could become a heavy, rare neon-oxygen white dwarf whose size would be no larger than the Earth. What makes Enif so cool is that it is very unpredictable. According to records, in 1972 Enif had a flare event which caused it to brighten 5 times more than its normal stellar magnitude!

Keep your binoculars handy, because following the trajectory from Theta to Epsilon just another third of the way will bring you to awesome globular cluster – Messier 15 (RA 21:29:58.3 Dec +12:10:01). Located almost equidistantly from both the galactic center and from us, this superior globular cluster was first discovered by Jean-Dominique Maraldi on September 7, 1746 and later listed by Charles Messier on his famous Messier Catalog list of “objects which are not comets”. It ranks third in variable star population and M15 is perhaps the oldest and most dense of all globulars located in the Milky Way Galaxy. Its compact central core may be the result of mutual gravitational interaction, or it could contain a dense, supermassive object – a black hole. One thing we do know that M15 contains is a planetary nebula known as Pease 1 – only four known planetary nebulae in Milky Way globular clusters! Another curiosity is M15 also contains 9 pulsars, the remnants of ancient supernova explosions leftover from its youthful beginnings. While you can easily see M15 with binoculars, even a small telescope can begin resolution on this great deep sky object!

For telescopes, have a look at spiral galaxy NGC 7217 (RA 22:07.9 Dec +31:22). This magnitude 10 jewel displays a bright nucleus and hazy frontier over its generous 3.7 arc minute size. Taken photographically this particular galaxy exhibits very tight spiral galaxy structure and is sometimes considered an “unbarred” spiral galaxy with a dark ring of obscuring material around the nucleus.

Try your hand at spiral galaxy NGC 7814 (RA 0:03.3 Dec +16:09), too. At magnitude 10 and a huge 6.3 arc minutes in diameter, this particular galaxy is easily seen in small telescopes and larger binoculars. Often referred to as Caldwell 43, it’s located about 40 million light years from Earth and gives a great edge-on presentation! It is sometimes referred to as the a miniature version of Messier 104, or “the Little Sombrero”.

Now, it’s time for NGC 7331 (RA 22:37.1 Dec +34:25). Easily spotted in big binoculars and small telescopes under dark skies, it was first discovered by Sir William Herschel. This beautiful, 10th magnitude, tilted spiral galaxy is very much how our own Milky Way would appear if we could travel 50 million light-years away and look back. Very similar in structure to both our own Milky Way and the Great Andromeda Galaxy, this particular galaxy gains more and more interest as scope size increases – yet it can be spotted with larger binoculars. At around 8″ in aperture, a bright core appears and the beginnings of wispy arms. In the 10″ to 12″ range, spiral patterns begin to emerge and with good seeing conditions, you can see “patchiness” in structure as nebulous areas are revealed, and the western half is deeply outlined with a dark dustlane. But hang on… Because the best is yet to come!

Return to NGC 7331 with a big telescope. What we are about to look at is truly a challenge and requires dark skies, optimal position and excellent conditions. Now breathe the scope about one half a degree south-southwest and behold one of the most famous galaxy clusters in the night. In 1877, French astronomer Edouard Stephan was using the first telescope designed with a coated mirror when he discovered something a bit more with NGC 7331. He found a group of nearby galaxies! This faint gathering of five is now known as “Stephan’s Quintet” and its members are no further apart than the diameter of our own Milky Way galaxy.

Visually in a large scope, these members are all rather faint, but their proximity is what makes them such a curiosity. The Quintet is made up of five galaxies numbered NGC 7317, 7318, 7318A, 7318B, 7319 and the largest is 7320. Even with a 12.5″ telescope, this author has never seen them as much more than tiny, barely-there objects that look like ghosts of rice grains on a dinner plate. So why bother? Because I’ve seen them with large aperture… What our backyard equipment can never reveal is what else exists within this area – more than 100 star clusters and several dwarf galaxies. Some 100 million years ago, the galaxies collided and left long streamers of their materials which created star forming regions of their own, and this tidal pull keeps them connected. The stars within the galaxies themselves are nearly a billion years old, but between them lie much younger ones. Although we cannot see them, you can make out the soft sheen of the galactic nuclei of our interacting group. Enjoy their faint mystery!

There are many more faint galaxies and deep sky objects in Pegasus to be enjoyed, so grab a good star map and fly with the “Winged Horse”!

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

Located south of the ecliptic plane, the constellation of Pavo was created by Petrus Plancius from the observations of Dutch navigators, Pieter Dirkszoon Keyser and Frederick de Houtman. It first appeared on Plancius celestial globe in the late 1500s and was included in Johann Bayer’s Uranometria of 1603. It was later adopted as one of the 88 modern constellations by the International Astronomical Union in 1930. Pavo covers 378 square degrees of sky and ranks 44th in size. It has 7 main stars in its asterism and contains 24 stars with Bayer Flamsteed designations within its confines. Pavo is bordered by the constellations of Octans, Apus. Ara. Telescopium and Indus. It is visible to observers located at latitudes between +30° and ?90° and is best seen at culmination during the month of August.

There is one annual meteor shower associated with Pavo which peaks on or about April 4, but the activity for this variable meteor shower can begin as early as March 29 and end as late as April 8. The hourly activity rate averages about 5-7 meteors per hour and the parent comet would appear to be comet Grigg-Mellish, but it has not yet been confirmed.

Since Pavo is considered a “new” constellation, there is no mythology associated with it. The term “Pavo” in Latin denotes the “peacock” and the constellation is often depicted as this highly colorful bird and associated with Indus the Indian. The Dutch explorers would have encountered a new species of peacock during their travels, and perhaps this is what prompted them to so name the constellation.

We begin our binocular tour of Pavo with a look at its brightest star – Alpha – the “a” symbol on our map. Named Peacock, this blue subgiant star is also a spectroscopic binary star and is located about 187 light years from Earth. Only a fraction larger than our Sun, Peacock burns blue because it’s much hotter. How hot? Try a has surface temperature of 11000 to 28000 Kelvin. It’s a nice color contrast to nearby, cooler Beta Indi!

Now, take a look at Beta – the “B” symbol on our map. It’s a massive A-type star. Hop west for Delta, the “8” symbol. Delta is just barely 20 light years away from our own solar system and it’s very interested because it is almost identical to our own Sun. So identical, in fact, that Delta has become one of the top 100 target stars for NASA’s planned Terrestrial Planet Finder (TPF)!

In the mood for a visual double star? The drop south towards the celestial pole for Upsilon 1 and 2 – the “u” symbol on our map. While the two Upsilons aren’t physically related to each other, they make a pleasing pair in binoculars and to acute vision!

Keep your binoculars or small telescopes on hand for globular cluster NGC 6752 (RA 19:10:51.8 Dec -59:58:55). At about magnitude 5.5, this sturdy little globular cluster was discovered by James Dunlop on July 28, 1826, but may have been noted by Abbe Lacaille in 1751-52. Look for a well condensed core region in this highly evolved galactic gem!

For a more challenging telescope object, try spiral galaxy NGC 6744 (RA 19:09:46.1 Dec -63:51:27). Located about 25 million light years away from our own Milky Way Galaxy, this spiral has a lot in common with our own – including spiral galaxy structure – and at least one distorted companion galaxy which is vaguely similar to one of the Magellanic Clouds.

Try your hand a barred spiral galaxy, NGC 6684 (RA 18:49.0 Dec -65:11), too. At one time, Helen Sawyer Hogg has this object listed as a globular cluster! At magnitude 10.5, it’s a good target for mid-sized telescopes, and a prized study for velocity and velocity dispersion and stellar kinematics as well.

For large telescopes, try NGC 6753 (RA 19:11.4 Dec -57:03). At magnitude 12 and about 2 arc minutes in size, this face-on spiral galaxy not going to be the easiest you’ve ever tried, but it was home to a bright supernova event in 2000!

Sources:
Wikipedia
SEDS
Chart courtesy of Your Sky.

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The constellation of Orion resides on the celestial equator and is one of the most brilliant and recognized in the world. It was part of Ptolemy’s original constellation charts and remains as one of the 88 modern constellations adopted by the International Astronomical Union. Orion spans 594 square degrees of sky, ranking 26th in overall size. It contains 7 main stars in its asterism and has 81 Bayer Flamsteed stars within its confines. Orion is bordered by the constellations of Gemini, Taurus, Eridanus, Lepus and Monoceros. It is visible to all observers located at latitudes between +85° and ?75° and is best seen at culmination during the month of January.

Orion has one annual meteor shower associated with it which occurs during an eight day window around the date of October 20, with the peak on the early morning hours of that date. The Orionid meteor shower radiant – or point or origin – is near the border of the constellation of Taurus and the fall rate averages about 30 per hour visible during optimum conditions – such as a moonless night. These particular meteors are rated at very fast, with speeds recorded of up to 67 kilometers per second upon entry into the Earth’s atmosphere. The Orionids are also noted for color – the trails appearing in shades of red, blue or yellow – and leaving long, lasting trains. While the peak occurs on October 20, look for activity to begin on the morning of October 16 and last through around October 24.

Because the stellar patterns of Orion are so vivid and symmetrical, this constellation has been recognized throughout history and has a long and colorful mythology associated with it. Orion is meant to represent the celestial “Hunter” and the three bright “belt” stars are recognized around the world. Orion is often depicted as standing in the river Eridanus, holding his bow before him, with the club raised over his head – while his hunting dogs (Canis Major and Minor) trail behind and the rabbit (Lepus) hides at his feet. Some myths have Orion killed by the scorpion (Scorpius) and others have him associated with fighting the bull (Taurus) and with the Plieades. Because Orion is viewed at a different angle in the Southern Hemisphere, it is often called the “Saucepan” and cultural mythology also differs. No matter how you see this great collection of stars, you’ll find it leads to an even greater collection of deep sky objects! So many, if fact, that a simple star chart would become quickly overloaded if we were to list them all!

Let’s begin our visual and binocular tour of Orion with its brightest star, Alpha – the “a” symbol on our map. Located in the northeastern corner of Orion and about 425 light years from our solar system, Betelgeuse, like many red giant stars, it is inherently unstable – varying irregularly by as much 1.3 magnitudes in cycles up to six years in length. At its brightest, Betelgeuse can appear more luminous than Rigel (Beta) and its diameter could encompass all the inner planets and much of the asteroid belt. Due to low density, observers would have a hard time determining where space ended and the star began! Allowing for all ranges of radiation, Betelgeuse is more than 50,000 times brighter than our own Sun. Like Antares, it is a “star within a star” – its dense core region radiating with such ferocity that internal pressure drives matter away. Betelgeuse’s core has probably fused all its hydrogen and is now releasing energy through helium fusion – resulting in atoms essential to organic life (carbon and oxygen). Even though it hasn’t gone supernova yet, when it does it will outshine the Moon!

Now, hop to the southwest corner for a look at Beta Orionis – the “B” symbol on our map. Known as Rigel and located about 775 light years from Earth, this hot, blue supergiant star shines with the light of 40,000 suns. If we were to include the amount of light that Rigel produces in the ultra-violet spectrum, too it would produce up to 66,000 times as much light as Sol! But, Rigel also holds a surprise. Point even a small telescope its way and you’ll find out that Beta Orionis is a binary star. Its 7th magnitude companion is separated well away, but you’ll need to keep Rigel to the edge of the field of view to cut the brilliance in order to see it. This small companion orbits about 50 Pluto distances away from its giant companion… which is a good thing since it one day may explode!

Take a look at Gamma Orionis – the “Y” symbol on our map. Bellatrix is known as the “Amazon Star” and is about 240 light years away. While it was once believed to be associated with the other stars of Orion, we’ve learned that Bellatrix is a star in its own right – separate from the others. Historically is was used to measure stellar luminosity until it was discovered that it was an eruptive variable star! While you won’t much notice a tenth of a magnitude change in the 27th brightest star in the sky, it’s still cool to know that it’s collecting a dusty hood that fooled astronomers for many years!

Don’t forget to look at Kappa Orionis, too – the “k” symbol on our map. Even though Saiph is about the same distance away and same size as Rigel, it sure doesn’t look the same, does it? Why? Because Saiph is a much hotter star and most of its light is emitted in the ultraviolet range. It, too, is destined to lead a short, violent stellar life – ending a supernova.

For other interesting stars to take a look at in binoculars, check out U Orionis – it’s a Mira-type variable star. Most of the time U holds an average magnitude of 4.8, Mira-type regular variable is U Orionis, which usually has a brightness of 4.8 but every 368.3 days it drops down to a telescopic magnitude 13! Pi 5 Orionis is a nice visual double star, but even a small telescope and will thoroughly enjoy Sigma Orionis – a true multiple star system. Don’t forget Lambda, too! It’s also a great telescopic binary star!

Because Orion is so loaded with deep sky objects, we’ll only touch on a few of the great for binoculars and telescopes. Absolutely one of the best is Messier 42 located in the asterism of “Orion’s Sword”. Known as the Great Orion Nebula – M42 is actually a great cloud of glowing gases whose size is beyond our comprehension. More than 20,000 times larger than our own solar system, its light is mainly fluorescent. For most people, the Great Orion Nebula will appear to have a slight greenish color – the result of doubly ionized oxygen. At the fueling heart of this immense region is an area known as the Trapezium, its four easily seen stars perhaps the most celebrated multiple system in the night sky. The Trapezium itself belongs to a faint cluster of stars which are now approaching the main sequence stage in an area known as the “Huygenian Region”. Buried in this cloud of mainly hydrogen gas there are many star forming regions amidst the bright ribbons and curls. Appearing like “knots” in the structure, these are known as “Herbig-Haro objectsâ€? and are believed to be stars in their earliest states. There are also a great number of faint reddish stars and erratic variables – very young stars that may be of the accreting T Tauri type. Along with these are “flare starsâ€? whose rapid variations mean that amateur astronomers have a chance to witness new activity. While you view M42, note that the region appears very turbulent. There is a very good reason. The Great Nebula’s many different areas move at different speeds both in recession and approach. The expansion rate at the outer edges of the nebula is an indication of radiation from the very youngest stars known. Although it may be as many as 23,000 years since the Trapezium brought it to “light” it is entirely possible that new stars are still forming in M42. Don’t forget the area of nebulosity that appears slightly separate is designated as M43!

Now, let’s check out the “Running Man” in a large telescope. Located just a half a degree north of M42/43, this tripartite nebula consists of three separate areas of emission and reflection nebulae that seem to be visually connected. NGCs 1977, 1975 and 1973 would probably be pretty spectacular if they were a bit more distant from their grand neighbor! This whispery soft, conjoining nebula’s fueling source is multiple star 42 Orionis. To the eye, a lovely triangle of bright nebulae with several enshrouded stars makes a wonderfully large region for exploration. Can you see the “Running Man” within?

Ready for some open star clusters for your binoculars and telescopes? Hop about four fingerwidths southeast of Betelgeuse for NGC 2186. This large, loose open cluster is well suited to larger binoculars or small telescopes and contains around 50 or so members that range in magnitude from 9 to 11. Look for many distinct pairings! NGC 2186 has been a study area for astronomers and is known to contain circumstellar disks, which may be either newly-forming solar systems or just regenerated materials left over from formation. The next hop is just northwest of apparent double Kappa Orionis. NGC 2194 is also a Herschel object and at magnitude 8.5 is well suited to smaller scopes. This rich galactic cluster can be well resolved in larger scopes and the similar magnitude members make it a delightful spray of stars.

Now, let’s look at some galactic star clusters that belong to different catalogs. The first three are known as “Dolidzes” and your marker star is Gamma Orionis. The first is an easy hop of about one degree northeast of Gamma – Dolidze 21. Here we have what is considered a “poorâ€? open cluster. Not because it isn’t nice – but because it isn’t populous. It is home to around 20 or so low wattage stars of mixed magnitude with no real asterism to make it special. The second is about one degree northwest of Gamma – Dolidze 17. The primary members of this bright group could easily be snatched with even small binoculars and would probably be prettier in that fashion. Five very prominent stars cluster together with some fainter members that are, again, poorly constructed. But it includes a couple of nice visual pairs. Low power is a bonus on this one to make it recognizable. The last is about two degrees north of Gamma – Dolidze 19. Two well-spaced roughly 8th magnitude stars stand right out with a looping chain of far fainter stars between them and a couple of relatively bright members dotted around the edges. With the very faint stars added in, there are probably three dozen stars all told and this one is by far the largest concentration of this “Do” trio.

Now let’s have a look at a deceptive open cluster located in Barnard’s Loop around 2 degrees northeast of bright nebula M78. While billed at a magnitude of roughly 8, NGC 2112 might be a binocular object, but it’s a challenging one. This open cluster consists of around 50 or so stars of mixed magnitudes and only the brightest can be seen in small aperture. Add a little more size in equipment and you’ll find a moderately concentrated, small cloud of stars that is fairly distinguishable against a stellar background. Also known as Collinder 76, this unusual cluster resides in the galactic disc – an area of mostly very old, metal poor stars. It is believed that NGC 2112 is of a more intermediate age, based on recent photometric and spectroscopic data.

Are you ready for a challenge? Then take advantage of dark sky time to head to the eastern-most star in the belt – Zeta Orionis. Alnitak resides at a distance of some 1600 light-years, but this 1.7 magnitude beauty contains many surprises – like being a triple system. Fine optics, high power and steady skies will be needed to reveal its members. About 15′ east and you will see that Alnitak also resides in a fantastic field of nebulosity which is illuminated by our tripartite star. NGC 2024 is an outstanding area of emission that holds a rough magnitude of 8 – viewable in small scopes but requiring a dark sky. So what’s so exciting about a fuzzy patch? Look again, for this beauty is known as the Flame Nebula.

Larger telescopes will deeply appreciate this nebula’s many dark lanes, bright filaments and unique shape. For the large scope, place Zeta out of the field of view to the north at high power and allow your eyes to re-adjust. When you look again, you will see a long, faded ribbon of nebulosity called IC 434 to the south of Zeta that stretches for over a degree. The eastern edge of the “ribbonâ€? is very bright and mists away to the west, but look almost directly in the center for a small dark notch with two faint stars to the south. You have now located one of the most famous of the Barnard dark nebulae – B33. B33 is also known as the Horsehead Nebula. It’s a very tough visual object – the classic chess piece shape is only seen in photographs – but those of you who have large aperture can see a dark “nodeâ€? that is improved with a filter. B33 itself is nothing more than a small area cosmically (about 1 light-year in expanse) of obscuring dark dust, non-luminous gas, and dark matter – but what an incredible shape. If you do not succeed at first attempt? Do not give up. The “Horsehead” is one of the most challenging objects in the sky and has been observed with apertures as small as 150mm.

Now challenge yourself to a 6th magnitude open cluster just northwest of the top star in Orion’s bow (RA 04 49 24 Dec +10 56 00) as we have a look at NGC 1662. Discovered on this night in 1784 and cataloged as H VII.1 by Sir William Herschel, it won’t make the popular lists because it’s nothing more than a double handful of stars…or is it? Studied extensively for proper motion, this galactic cluster may have once held more stars earlier in its lifetime. Enjoy its bright blue and gold members and mark your notes for locating a binocular deep sky object!

Orion is filled with many more great deep sky objects, so get a good star chart and go hunting with the “Hunter”!

Sources:
Wikipedia
Chandra Observatory
Star chart courtesy of Your Sky.

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The sprawling constellation of Ophiuchus sits on the celestial equator and was one of the 48 original constellations charted by Ptolemy and later adopted by the IAU. Of the 13 zodiacal constellations (constellations through which the Sun passes during the course of the year), Ophiuchus is the only one not designated as an astrological sign. It covers 948 square degrees of sky and ranks 11th in size. Ophiuchus contains 10 main stars in its asterism and has 62 Bayer Flamsteed designated stars within its confines. Ophiuchus is bordered by the constellations of Hercules, Serpens Caput, Libra, Scorpius, Sagittarius, Serpens Cauda and Aquila. It is visible to all observers at latitudes between +80° and ?80° and is best seen at culmination during the month of July.

There is one well documented annual meteor shower associated with the constellation of Ophiuchus which peaks on or about June 20 of each year – the Ophiuchids. The radiant – or point of origin – for this meteor shower is near Sagittarius border. The fall rate varies from average 8 to 20 meteors per hour, with occasionally many more. Watching on a Moonless night when the constellation is at its highest will greatly improve the amount of meteors you see!

At one time, the constellation of Ophiuchus was referred to as “Serpentarius”, whose name literally meant the “serpent bearer”. In most mythology representations, you’ll see Ophiuchus represented as a man grappling with a large snake; his body representing the division of the snake “Serpens” into two parts – Serpens Caput and Serpens Cauda. Even though divided by Ophiuchus, they still are only one constellation. It is possible the mythological figure could represent the healer Asclepius, placed close to Chirion (Sagittarius), his mentor. The man could also be the Trojan priest Laocoön, who was killed by a pair of sea serpents after warning about the Trojan Horse. It could even be Apollo wrestling with the Python to take control of the oracle at Delphi…. But no matter which figure you choose, this huge constellation holds a vast number of deep sky riches just waiting to be explored!

Let’s begin our binocular tour of Ophiuchus with its brightest star – Alpha – the “a” symbol on our map. Located about 47 light years distant from Earth, Rasalhague is an A-type giant star that’s recently exhausted its core hydrogen reserves. But, “the Head of the Serpent Collector” isn’t alone, but Rasalhague is a binary star. Power up in a telescope to look for a faint, very close companion only 0.5″ away.

Head on next to Beta Ophiuchi, the “B” symbol on our map. This K-type giant star is located about 82 light years from our solar system and its proper name is Cheleb. Also known as 44 Oph, we have something of a mystery star here. Precise radial velocity measurements taken over 8 consecutive nights in 1992 June and 2 nights in 1989 July revealed the presence of a 0.255 +/- 0.005 day period. A pulsing variable star! It’s easy to catch in binoculars, but you might want a telescope for what’s nearby…

It’s called Barnard’s Star and found due east of Beta (RA 17:57:48.5 Dec +04:41:36). Located approximately 6 light-years away from, Barnard’s Star is a very low-mass red dwarf star. In 1916, American astronomer E. E. Barnard measured its proper motion as 10.3 arc seconds per year, which remains the largest known proper motion of any star relative to the Sun. Even though it’s an ancient star at 7 to 12 billion years old, there are still possibilities of flare events – such as one that occurred in 1998. The flare was surprising because intense stellar activity is not expected around stars of such age.

Now have a look at Eta Ophiuchi – the “n” symbol on our map. This time you’ll want a telescope because Sabik is a difficult to split binary star system. Here we have two fairly unremarkable A class main sequence stars – close to equal in magnitude and not anything special if taken apart. However, together the Eta binary is strange because they orbit around a common center in a very fast and highly elliptical path.

Now put your binoculars on Deta – the “8” symbol on our map. Known as Yed Prior, you’ll quickly notice it is an optical double star with Epsilon whose name is Yed Posterior. Delta Ophiuchi is a red giant star located 170 light years from our solar system, while Epsilon is 108 light years away and a G-class giant star. These two are important, because they’ll guide you to our next two objects to the east.

For binoculars and telescopes, it’s time to enjoy some of Ophicuhus many Messier Catalog riches and we star with the giant globular clusters, M10 and M12. You’ll find Messier 10 located at RA 18:57:0 Dec -04:05:57. Discovered by Charles Messier on May 29, 1764 this awesome globular cluster hangs out about 4,300 light-years and spans about 23 light years of space. You can see it easily in binoculars, but it will require a telescope to begin resolving stars. Nearby, Messier 12 (RA 10:47:14 Dec -01:58:52) is also an all instruments type of globular cluster, but with a much looser structure. Why? A study published in 2006 revealed that M12 may have lost as many as one million of its low mass stars to the gravitational influence of the Milky Way!

Large telescopes will love Messier 19 (RA 17:02.6 Dec -26:16). It’s one of the most oblate globular clusters in the sky and thanks to the work of Harlow Shapely, we’ve learned to take a better look, because he estimated there are twice as many stars along M19’s major axis than along its minor. This rich, dense globular cluster was one of Charles Messier’s original discoveries, but Sir William Herschel was the one to resolve it into “countless stars of mag 14, 15, 16”.

Try your hand with Messier 107 (RA 16:32.5 Dec -13:03). This 20,000 light year distant globular cluster is full, too! Discovered by Pierre Méchain in April, 1782 and later added to Messier’s catalog by Helen Sayer Hogg, this one is also a resolution delight in larger telescopes. Look for some dark obscured regions. According to SEDS: the star distribution is called “very open” by Kenneth Glyn Jones, who points out that this cluster “enables the interstellar regions to be examined more easily, and globular clusters are important `laboratories’ in which to study the process by which galaxies evolve.”

Don’t forget Messier 63 (RA 17:01.2 Dec -30:07)! It’s another globular cluster whose distortion by our own Milky Way’s influences are easily apparent in a telescope. Thanks to studies by the Chandra X-Ray Observatory, we know it contains a large number of X-ray binaries, proving that M63 has undergone core collapse.

How about Messier 14 (RA 17:37:36.1 Dec -03:14:45). Spanning across 101 light years of space and located about 30,000 light years away, this magnificent globular cluster is often overlooked. Discovered by Charles Messier on June 1, 1764, this bright ball of stars is near magnitude 7 and well within range of binoculars and small telescopes. M14 had a nova occur in 1948, but it wasn’t discovered until 1964 when the photographic plates were being surveyed. It wasn’t done with surprises either… In an area where all stars should be about the same age, a carbon star was discovered in 1997!

For challenging large telescope studies, take a look at three planetary nebulae. NGC 6309 (RA 17:14.1 Dec -12:55) is often referred to as the “Box Nebula”, for its unique structure. Far brighter NGC 6572 (RA 18:12.1 Dec +06:51) has the wonderful nickname of the “Blue Racquetball”. In his observing notes, Walter Scott Houston writes: Walter Scott Houston wrote, “My old 10-inch reflector showed the vivid green color of the object with any power more than 50x. It is interesting to note that older observers have described NGC 6572 as green, while the younger ones tend to call it vivid blue.”. I see blue… Do you? And don’t forget to try NGC 6369 (RA 17:29:20.4 Dec -23:45:35)… the “Little Ghost” is a seasonal favorite!

There’s many, many more wonderful objects just waiting in Ophiuchus for you to explore. Be sure to get a good star chart and you’ll see why the “Serpent Bearer” still stands grasping the stars… There’s so much to do!

Sources:
SEDS
Chandra Observatory
Chart Courtesy of Your Sky.