CAPRICORNUS The "The Sea Goat" pronounced KAP-rih-KOR-nus

Chart showing the constellations.

Capricornus is depicted as a goat with a fish tail. Amphibious creatures feature prominently in ancient legends, and the origin of Capricornus dates back to ancient times. Ptolemy assigned twenty-eight stars to this group which is not conspicuous but easily recognised by the two stars α and β Cap, following Sagittarius, the former being a pair to the unaided eye.

About 2,500 years ago the Sun used to reach its farthest point south of the equator in Capricornus on the winter solstice, December 22nd (northern hemisphere). The latitude on Earth, 23.5° south, at which the Sun appears overhead at noon on the winter solstice, therefore became known as the Tropic of Capricorn. Because of precession, the (northern) winter solstice has now moved into the neighbouring constellation of Sagittarius, but the Tropic of Capricorn retains its name.

To find Capricornus, look north in the late evening, over halfway up the sky to find alpha and beta Cap about halfway between the bright stars Fomalhaut and Altair.

Chart showing the Constellation.

Capricornus. 7.1 kb

Constellation Sagittarius Constellation Microscopium Constellation Grus Piscis Austrinus Constellation Aquarius Delphinus & Equuleus Constellation Aquila

Some stars and interesting objects in the Constellation

α Capricorni (Algedi or Giedi, meaning goat or ibex) is a multiple star, consisting of two unrelated yellow and orange stars 1600 and 120 light years away, of magnitudes 4.2 and 3.6 respectively, seen separately with the unaided eye or binoculars. Larger telescopes reveal that each star is itself double.

α1 Cap, the fainter of the pair, has a wide 9th magnitude unrelated companion, visible in small telescopes. α2 Cap is a genuine binary star, with an 11th magnitude companion. Telescopes of greater than 100 mm aperture show that this faint companion is itself composed of two close 11th magnitude stars.

β Cap (Dabih, meaning 'lucky one of the slaughterers') is a magnitude 3.1 golden yellow star 250 light years away. It has a wide blue magnitude 6 companion, visible in binoculars or small telescopes. The brightest star is really five connected stars, shown by a mixture of spectroscopic and occultation techniques.

γ Cap (Nashira, the fortunate one) is a magnitude 3.7 white star 100 light years distant.

δ Cap (Deneb Algiedi, goat's tail) at magnitude 2.9 is the brightest star in the constellation. It is an eclipsing binary star, varying by a barely perceptible 0.2 magnitude every 24½ hours. It lies 49 light years away.

π Cap is a magnitude 5.3 blue-white star, with a close magnitude 8.5 companion 470 light years away, visible in small telescopes as a fine pair in a field of widely scattered stars..

M 30 (NGC 7099) is a beautiful 8th magnitude globular cluster 40,000 light years away, visible in small telescopes. The well-resolved centre is compressed and two short straight rays of stars emerge north-west, while from the northern edge irregular streams of stars come out almost spirally eastwards.

Visibility

Capricornus will be to the north, high in the sky late evening at the beginning of September and at mid evening by the end of the month. It will remain visible in the evening sky through October and November, but by the end of the latter month will be getting rather low to the west as the sky darkens after sunset.

Since the constellation is some way south of the equator it is above the horizon as seen from New Zealand for about fourteen and a half hours.

CANIS MAJOR and CANIS MINOR, (pronounced KAY-niss MAY-jer and KAY-niss MY-ner)

Chart showing Canis Major and Canis Minor

These are ancient constellations, representing the two dogs following at the heels of Orion. To find them look north late evening, find Orion (Pot) and follow the map.

Canis Major, the large dog, is a conspicuous constellation lying mainly just south of the Milky Way between Orion and the long train of bright stars from the old Argo Navis. The constellation is dominated by the brilliant white Sirius (the Dog Star) (pronounced SIH-rih-uss), the brightest appearing star in the sky. The ancient Egyptians based their calendar on its yearly motion around the sky.

Canis Minor, the small dog, had two stars assigned to it in ancient times. The brightest of these is Procyon.

Chart showing the two constellations as seen high in the sky to the north mid evening in February.

Canis Major and Minor.

Constellation Caelum Constellation Columba Constellation Puppis Constellation Pyxis Constellation Monoceros Constellation Cancer Constellation Orion Constellation Lepus

Details of some of the objects shown in the chart.

α Canis Majoris, Sirius (from the Greek, meaning sparkling or scorching) at magnitude -1.46 is exceed only by some of the planets in apparent brightness. It owes its brilliance to being one of the Sun's closest neighbours at 8.7 light years away, and as well, is about 22 times more luminous than the Sun. Several other stars in Canis Major are in fact far more luminous, but not appear as bright due to their greater distance.

Sirius has a white dwarf companion that orbits it every 50 years. Closest approach was in 1993, while the widest separation will be in 2022. The white dwarf will not be visible to most backyard observers, however, until the early years of the 21st century. Even then it remains difficult to see because of the glare of Sirius. A white dwarf is only about the diameter of the Earth, but contains most (90%) of the star's original mass. White dwarfs are therefore exceptionally dense bodies. A teaspoonful of material would have a mass of thousands of kilograms or over 100,000 times that of water. Over thousands of millions of years they slowly cool off and fade.

β CMa, Mirzam is a magnitude 2.0 star which is 500 light years away. It has a luminosity more than 3000 times that of the Sun.

δ CMa, Wezen is a magnitude 1.8 star some 1800 light years distance. It has a luminosity more than 30000 to 40000 times that of the Sun.

ε CMa, Adara is a magnitude 1.5 star which is 430 light years away. It has a luminosity about 4000 times that of the Sun.

η CMa, Aludra is a magnitude 2.5 star and is 3000 light years away. This large distance means it has a luminosity some 9000 times that of the Sun.

M 41 (NGC 2287) is a fine open cluster recorded by Messier in 1765, but was known to Aristotle around 325 BC, being visible to the unaided eye. It is a beautiful object in binoculars and small telescopes, containing some delicate pairs and triplets, with a fine orange star near the centre. It lies about 2500 light years away.

NGC 2362 is a most beautiful smaller and fainter cluster than M 41, but it is easily found surrounding the 4.4 magnitude blue giant star τ CMa. Small telescopes and binoculars show about 40 stars in the cluster. τ CMa is also a member of the cluster which lies about 4000 light years away.

α Canis Minoris, Procyon (pronounced PROH-see-on), a brilliant yellow star about five times more luminous than the Sun lying 11.3 light years away. It's name comes from the Greek, meaning 'before the dog', referring to its rising before Canis Major. Like Sirius, Procyon has a white dwarf companion. This one orbits every 41 years, but is even more difficult to see than the companion to Sirius, requiring the use of large professional telescopes.

β CMi is a magnitude 2.9 star which is 170 light years away and has a luminosity more than 160 times that of the Sun.

Visibility

Sirius transits, when it is to the north and at its highest, at 10 pm (NZDT) about February 20. It, and Canis Major, remain visible in the evening sky until late June when they are low to the west at the end of evening twilight. By then Sirius will also be visible in the morning twilight low to the east. The constellation is in the late evening sky by late November, again to the east.

Canis Minor is considerably further north in the sky than Canis Major, so is above the horizon in New Zealand for a shorter time. 10 pm transit is also a little later, about 1 week into March. Procyon sets only about 15 minutes before Sirius, so also remains visible in the early evening until late June. On the other hand it rise about 2 hours after Sirius, so is a month later appearing in the morning sky. It is well into December before Canis Minor appears in the late evening sky.

CORONA BOREALIS "the Northern Crown" and CANES VENATICI "the Hunting Dogs"
(Pronounced koh ROH-nah BOH-ree-AL-liss and KAY-neez veh-NAT-ih-sigh)

Chart showing the constellation.

Corona Borealis was known to the ancient Greeks as the "wreath". Only later was the adjective "northern" added to distinguish it from its southern counterpart. It represents the jewelled crown given as a wedding present by Bacchus to Ariadne, and cast into the sky by him, upon her death. Another legend has it as the golden crown given to Ariadne by Theseus after the quest in the labyrinth to kill the Minotaur. It is a lovely arc of 4th magnitude stars, with a second magnitude star (Gemma) set as a central gem.

Canes Venatici is a constellation introduced by the Polish astronomer Hevelius in 1690 in his great star atlas Uranometria. The sprinkling of faint stars was taken from the constellation Ursa Major, the Great Bear. It represent the dogs Asterion and Chara held on a leash by Boötes the herdsman as they pursue the Great Bear round the north pole.

To find these constellations look low to the north in the evening sky, find the bright reddish star Arcturus in Boötes and look either side. Canes Venatici is to the left (west) and the more easily seen Corona Borealis is the arc of stars to the right (east).

Chart showing Corona Borealis and Canes Venatici.

The chart shows the sky to the north at about 11.30 pm (NZST) in mid May or 9.30 pm mid June. The horizon shown is for central New Zealand.

Corona Borealis and Canes Venatici Constellation Serpens Constellation Ophiuchus Constellation Hercules Constellation Bootes Constellation Virgo Coma Berenices

Some stars and interesting objects in the Constellations

α Coronae Borealis (Gemma or Alphecca) is a magnitude 2.2 blue-white star 75 light years away. It is an eclipsing binary of the Algol type, but it varies only 0.1 in magnitude, which is too slight to be seen visually.

R CrB is a remarkable star. It is hydrogen poor and carbon rich. Its variability was discovered by Pigott in 1795. Violent changes are happening in its corona and chromosphere, and these are reflected in its brightness, which can be between 6th magnitude and 14th magnitude. It is a prototype star for a class of variable stars.

α Canum Venaticorum is popularly called Cor Caroli, meaning Charles' heart. This is a reference to King Charles I of England. It is said to have shone brightly in 1660 on the arrival of Charles II in England at the Restoration of the Monarchy. It is a double star, the brighter having a magnitude of 2.9, with a magnitude 5.5 companion, visible in small telescopes. The brighter star is representative of the a CVn class of variable stars, with strong varying magnetic fields. These are probably evolving away from the main sequence of stars.

β CVn at magnitude 4.2 is the only other prominent star in the constellation. It is a yellow star 27 light years away and has a similar brightness to the Sun.


Visibility

The two constellations are a long way north of the equator and are low as seen from New Zealand. α CVn is above the horizon for only a little over 6 hours from Wellington, while α CrB is up for just over 8.5 hours.

Canes Venatici rises first and is due north and highest at about 10 pm mid May and 8 pm a month later. From mid New Zealand α CVn has a maximum altitude of about 10°. From Auckland it is rather higher at 15°, but from Invercargill it only rises 5° above the horizon. The constellation is so far north that, for most parts of New Zealand, the lower parts do not rise above the horizon.

Corona Borealis is due north about 150 minutes after Canes Venatici, that is about 10.30 pm mid June and 8.30 pm mid July. The constellation is smaller than Canes Venatici and not as far north. Consequently it rises a little higher in southern skies with α CrB being about 22° above the horizon as seen from Wellington.

Cancer, the Crab

Chart showing the constellation.

This constellation represents the crab that attacked Hercules when he was fighting the Hydra. The poor crab was crushed underfoot by mighty Hercules, and subsequently elevated to the heavens.

In ancient times in the northern hemisphere the Sun reached its most northerly point in the sky each year while it was in the constellation Cancer. The Sun reaches this point about June 21st, and this day is known as the summer solstice. On the summer solstice, the Sun appears overhead at latitude 23.5° north on Earth. This latitude is called the Tropic of Cancer. It retains this name today even though because of a wobble of the Earth called precession, the Sun now lies in the neighbouring constellation of Gemini at the summer solstice.

To find Cancer look north-east in the late evening sky, and find bright Regulus with the upside-down sickle below it, marking Leo the "Lion". To the left are bright Pollux and Castor and above them Procyon in Canis Minor. From a dark sky the fuzzy patch of M 44 will be apparent, and is really the main distinguishing feature of this otherwise inconspicuous constellation.

Chart showing the constellation as seen to the north at about 11.00 pm NZDT in mid March.

The chart is also valid for about 8pm NZST mid April and 7pm at the beginning of May.

Cancer and surrounding constellations

Constellation Canis Minor Constellation Hydra Constellation Sextans Constellation Leo Constellation Lynx Constellation Gemini

Details of some of the objects shown in the chart.

α Cancris (Acubens, meaning claws) is a magnitude 4.3 white star 174 light years away. It has an 11th magnitude companion visible in moderate telescopes.

β Cnc is a magnitude 3.5 orange giant star 290 light years away and the brightest star in the constellation.

γ Cnc (Asellus Borealis, Northern Donkey) is a magnitude 4.7 white star 158 light years away.

δ Cnc (Asellus Australis, Southern Donkey) is a magnitude 3.9 yellow giant star 136 light years away.

ζ Cnc is an interesting triple star. The period of the close pair is 59.7 years. The separation between the stars is appearing to widen and will reach its maximum in 2020. The period of the third star is probably many hundreds of years and there is probably also a white dwarf around the third star. The system is 83 light years away.

ι Cnc is 298 light years away and a double star that can even be made out in steadily held 7 power binoculars, and is an easy object for small telescopes. This magnitude 4.0 yellow giant star has a blue-white magnitude 6.6 companion.

M 44 (NGC 2632) Praesepe (The Manger) or the Beehive Cluster is a large open star cluster visible as a misty patch to the unaided eye from a dark sky site. It is best seen in binoculars or very small telescopes at low magnification to show the many stars that make up this cluster.  It lies about 520 light years away and appears to cover about three times the size of the Moon.  It was known to the ancient Greek Hipparchus, who called it a "Little Cloud". (Note the two Donkeys γ and δ flanking the Manger).

M 67 (NGC 2682) is a denser and smaller cluster than the Beehive, visible as a misty patch in binoculars or small telescopes.  This is one of the oldest of the open clusters and a recent age estimate is about four billion years.  It lies about 2700 light years away.

Visibility

Cancer lies to the north of the equator, consequently it is above the horizon as seen from mid New Zealand for only some 9.5 to 10 hours each day. By the end of April the constellation will be due north at about 7 pm, that is by the time the sky is completely dark following sunset.   The constellation remains visible in the early evening until June when it will be low to the north-west once the sky is dark.

CASSIOPEIA the Queen of Ethiopia, pronounced KASS-ee-oh-PEE-uh
CAMELOPARDUS (also spelt CAMELOPARDALIS) the Giraffe, pronounced kah-MEL-oh-PAR-dis or kah-MEL-oh-PAR-dal-iss

Chart showing the constellations.

Only the most southerly parts of Cassiopeia rise above the horizon in northern New Zealand. None of the brighter stars are visible.

Cassiopeia was the legendry beautiful and boastful Queen of Ethiopia, wife of King Cepheus and mother of Andromeda. She is depicted sitting in a chair in the sky. From the northern hemisphere, the constellation is easily recognized by its distorted "W" shape.

Camelopardus, the Giraffe, is a faint and obscure constellation invented by the Dutch astronomer Petrus Plancius, but came into prominence through a book by the German mathematician Jakob Bartsch, a son-in-law of Johannes Kepler, who also named Colomba and Monoceros.

These constellations are practically impossible to see from New Zealand. The horizon shown is for Auckland. Astronomers from North Cape will be able to see a little more of the constellations, conversely stargazers from locations more south in New Zealand would be able to see less.

Chart showing the constellations.
The view is to the north, towards the end of December. The horizon is for Auckland.

Cassiopeia and Camelopardus.

Constellation Pisces Constellation Perseus Constellation Auriga Constellation Taurus Constellation Gemini Constellation Aries Constellation Andromeda Constellation Triangulum


Details of some of the objects shown in the chart.

α Cassiopeiæ (Schedar) is a magnitude 2.2 red star, 230 light years away.

β Cas (Caph) is a magnitude 2.3 yellow star, 55 light years away.

γ Cas is a magnitude 2.2 white star, 610 light years away.

δ Cas (Ruchbah) is a magnitude 2.7 star, 100 light years away.


Visibility

The most southerly parts of Cassiopeia are visible from the North Island of New Zealand. They are highest in mid November at about 10.30 pm (NZDT). α Cas remains about 3° below the horizon as seen from Auckland and is immediately below (north of) M31, the Andromeda Galaxy. The most southerly bright star of the constellation, π Cas (mag 5.0), rises to 6° at Auckland, but is only just above the horizon at Wellington.

Camelopardus is all but entirely unobservable from the latitude of New Zealand. A sliver of the constellation rises for places north of Auckland, and in mid January graze along the northern horizon at about 10.30 pm (NZDT). From Cape Reinga the most southerly, 5th magnitude, stars get to be about 2.5° up.

FORNAX, pronounced FOR-naks,
HOROLOGIUM, pronounced HOR-uh-LOW-jee-um,
CAELUM, pronounced SEE-lum,
RETICULUM, pronounced reh-TICK-yah-lum.

Chart showing the 4 constellations.

These are modern constellations, originating in 1752, by the Frenchman Nicolas Louis de Lacaille, the first person to map the southern skies comprehensively, and none is easily identified, or obvious.

Fornax, the Furnace, was originally Fornax Chemica, the chemical furnace. It contains the Fornax cluster of galaxies at a distance of around 55 million light years. In addition it also contains the Fornax dwarf spheroidal galaxy, a cloud of very faint, scattered stars about 420,000 light years away, which is a satellite of the Milky Way Galaxy. This was discovered photographically and is notoriously difficult to see visually.

Horologium represents the Clock. One of the two globular clusters in Horologium, AM1, is the most distant in the Milky Way galaxy at 390,000 light years away. At 15th magnitude, it is too faint for normal amateur telescopes.

Caelum, the Chisel, represents the engraving tool or burin used by craftsmen in metal or ivory. It is one of the smallest and least obvious constellations in the sky, containing no stars brighter than magnitude 4.5.

Reticulum, the net was originally Reticulum Rhomboidalis, the system of lines in a eyepiece reticle. Reticulum contains one globular cluster, which is probably an outlier of the Large Magellanic Cloud, and is also too faint for small telescopes.

To find these constellations, look towards the zenith immediately above you in the late evening sky. Use Achernar, Canopus and the Magellanic Clouds to help locate the constellations from the map. Most of the brighter stars are around magnitude 4, so a dark sky is needed.

Chart showing the constellations with Fornax to the north at about 10.30 pm NZDT mid December.

Fornax, Horologium, Caelum, and Reticulum. 9.1 kb

Constellation Sculptor Constellation Phoenix Constellation Grus Constellation Indus Constellation Tucana Constellation Hydrus Constellation Dorado Constellation Pictor Canopus in Carina Constellation Eridanus Constellation Eridanus Constellation Cetus

Details of some of the objects shown in the chart.

α Fornacis is a yellow star of magnitude 4.1 with a close magnitude 6.6 companion.

β For is a magnitude 4.5 yellow giant star 200 light years away.

NGC 1097 is a large diffuse oval-shaped galaxy, with a conspicuous nucleus.

NGC 1316 is a galaxy that appears as an elliptical haze with a bright nucleus in a field with few scattered stars. NGC 1317 appears as a less bright galaxy slightly north.

NGC 1365 is the finest barred spiral galaxy for southern observers. It's distance is estimated at about 35 million light years, placing it in the foreground of the Fornax Cluster.

NGC 1379 is a fairly bright member of the Fornax Cluster in a star sprinkled field that contains several galaxies (mostly elliptical in shape).

 
α Horologii is a yellow star of magnitude 3.9

β Hor is a magnitude 5.0 white star 280 light years away.

 
α Caeli is a magnitude 4.5 white star 65 light years away.

β Cae is a magnitude 5.1 white star 55 light years away.

γ Cae is a magnitude 4.6 orange star 170 light years away, with a magnitude 8.5 companion, visible in moderately small telescopes.

δ Cae is a magnitude 5.1 blue-white star 750 light years away.

 
α Reticuli is a yellow giant star of magnitude 3.4 lying 390 light years away.

β Ret is a magnitude 3.9 orange star 55 light years away

ζ Ret is a wide unaided eye or binocular double star 40 light years away, with components of magnitudes 5.2 and 5.5. These yellow stars are similar to the Sun.


Visibility

These four constellations, either side of Eridanus, are well south of the equator, so remain visible in the evening sky for a large part of the year. Some part of Caelum pass overhead througout New Zealand. From New Zealand, Fornax will remain visible in evening skies until the end of March, Caelum and Horologium at least up until the end of April. Reticulum and the more southerly parts of Horologium are in fact circumpolar so are visible throughout the year.

Fornax is due north and highest at about 10.30 pm (NZDT) in mid December, while Caelum, the most easterly of the four, is highest at 10.30 pm mid January.

Boötes, pronounced boh-OH-teez, the Herdsman

Chart showing the constellation.

This constellation dates from ancient times, represents either a ploughman or a herdsman driving a Bear (Ursa Major) around the sky. The herdsman is often depicted holding the leash of the hunting dogs (Canes Venatici). The constellation's brightest star Arcturus means bearkeeper in Greek. Arcturus is the brightest appearing star in the northern hemisphere sky.

All the constellation cannot be seen from New Zealand. The chart shows the northern horizon for Auckland. More southerly places will see a little less of the constellation. From Invercargill β Boo rises only 4° above the horizon when due north and at its highest.

An abundant meteor shower called the Quadrantids appear to come from a northern point in Boötes. This area of the sky was once the constellation of Quadrans Muralis, the Mural Quadrant and the meteor shower is named after this defunct constellation. The Quadrantis meteors reach a peak of about 100 meteors per hour on January 3rd to 4th each year, although they are not spectacularly bright.

To find Boötes look north in the late evening sky, and find the bright orange-red star Arcturus.

Chart showing Boötes as seen to the north at about 9.00 pm (NZST) mid June.

Bootes and surrounding constellations

Serpens constellation Ophiuchus constellation Hercules constellation Virgo constellation Corona Borealis Canes Venatici Leo constellation Coma Berenices


Some stars and interesting objects in the Constellation

α Boötis (Arcturus), pronounced ark-TOO-russ, is the fourth brightest appearing star in the entire sky. Its magnitude is 0.05. It is a red giant, twenty seven times the diameter of the Sun, and lies 36.7 light years away. It appears orange-red to the unaided eye, so is easily recognised. Arcturus has a mass similar to that of the Sun, and it is believed that the Sun will swell up to become like Arcturus in around 5000 million years.

β Boo (Nekkar, corrupted from Arabic, meaning herdsman) is a magnitude 3.5 yellow giant star 219 light years away. It can not be seen from the south of the country.

γ Boo (Haris or Seginus), is a magnitude 3.0 yellow giant star 85 light years away.

δ Boo is a magnitude 3.5 white star 117 light years away

ε Boo (Izar, meaning girdle) is a celebrated double star, first measured by F. G. W. Struve in 1830. It is a yellow giant primary, with a white or bluish companion (by contrast) and when split by 100 power or more has an appearance that led to alternative name 'Pulcherrima' meaning most beautiful.

NGC 5466 is an uncondensed scattered globular cluster of faint stars needing a moderate telescope to be seen. It lies around 50,000 light years away


Visibility

Arcturus, α Boo, is to the north and highest in the sky at about 11.30 pm mid May, 9.30 pm mid June and 7.30 pm mid July. From Auckland its height above the horizon is 34°, while β Boo reaches about 13°.

The stars are nearly 10° lower as seen from the south of New Zealand at Invercargill, so that β skims the horizon with a maximum elevation of less than 3°.

Auriga "The Charioteer" (pronounced oh-RYE-gah)

Chart showing the constellations.

Auriga the Charioteer or Wagoner is a large ancient constellation, known to Babylonian and Greek astronomers, to which the Greek astronomer Ptolemy in 150 AD assigned fourteen stars. It is low in the sky and is partly hidden to observers in the south of New Zealand. (The sky view is for Auckland).

Auriga's leading star is Capella, the seventh brightest appearing star in the sky. It marks the Charioteer's left shoulder. The Greeks identified capella with the she-goat Amalthea who helped feed the infant Zeus. The stars ζ and η Aur are referred to as the Kids.

To find these constellations look north in the evening low down below Orion. From the north of New Zealand bright Capella should be visible. (It should be just visible from Christchurch with a good northern sky and very low horizon at just the right time: the maximum altitude of the star is about 1° above the horizon!)

Chart showing the constellation.  The horizon is for Auckland, stars will be lower further south.

Auriga seen to the north.

Taurus and the Pleiades Constellation Orion Constellation Gemini Constellation Canis Minor Constellation Monoceros Constellation Perseus Constellation Cetus Constellation Aries Constellation Eridanus

Details of some of the objects shown in the chart.

α Aurigae (Capella, the little she-goat) is a magnitude 0.08 yellow star 42.2 light years away. It is actually a spectroscopic binary star with the stars orbiting each other every 0.28480 years (104 days), although they do not eclipse.

β Aur (Menkalinan, shoulder of the Charioteer) is magnitude 3.5 white star 97 light years away.

ε Aur is a white supergiant star 2038 light years away that actually is an enigmatic eclipsing binary star with an exceptionally long period of 27.06971 years. Normally it shines at magnitude 3.0, but every 27 years it sinks to magnitude 3.8 for about a year. Its next eclipse should be in 2010.

ζ Aur is an amazing eclipsing binary star system. It consists of an orange giant star orbited every 972 days by a small blue companion star. During eclipses the stars apparent magnitude drops from magnitude 3.7 to3.97. The system lies 788 light years away.

θ Aur is a magnitude 2.6 blue-white star with a white magnitude 7.5 companion. This is a tough double to split. The stars lie 173 light years away.

M 36 (NGC 1960) is a fine cluster of about 60 stars discovered by Le Gentil in 1749. It is visible in binoculars and resolvable into stars with small telescopes. It has a central region and several irregularly curved arms, giving a roughly spiral pattern. It lies about 4000 light years away.

M 37 (NGC 2099) is the richest open cluster of stars in Auriga, with about 150 stars about 4500 light years away. The cluster appears as a hazy, unresolved patch in binoculars, but small telescopes resolve it into faint sparkling stardust, with a brighter orange star at the centre.

M38 (NGC 1912) was also discovered by Le Gentil in 1749. It is a fine scattered cluster. but with a rather empty centre, and showing roughly the form of a oblique cross. The stars are elegantly dotted in arcs and small groups. It lies about 3600 light years away. Next to it to the south-west, lies the small fuzzy blob of NGC 1907, a much smaller and fainter cluster.

NGC 2281 is a binocular cluster of about 30 stars 5400 light years away. In a telescope the stars appear arranged in a crescent, with the four brighter stars forming a diamond shape.

Visibility

Auriga lies well north of the celestial equator, as a result the entire constellation is only visible from the extreme north of New Zealand. The brightest star, Capella, rises above the horizon for places as far south as the latitude of Christchurch. At Christchurch its greatest altitude is only 1°, so a true horizon to the north would be needed to see the star which is above the horizon for only 2 hours. From Auckland, Capella is rises to about 7.5° and is above the horizon for over 5 hours.

In mid January, Capella is due north and highest at about 11 pm (NZDT), an hour later at the beginning of the month and an hour earlier at the end of the month.

ARIES "The Ram".

Chart showing the constellation.

ARIES, "The Ram", of Greek mythology, is the first constellation of the Zodiac, but one of the smallest. It is a very ancient star group, and although known by a variety of names in the historical records of early peoples, seems usually to have represented a sheep or ram. The modern name is due to the Romans for whom and the early Greeks it was associated with the legend of the golden fleece. Ptolemy recorded 13 stars in Aries in AD 150, and five additional stars to the north. The constellation is recognised by the narrow triangle of the brightest stars. In the southern hemisphere the evening rising of this triangle, balanced on its narrow apex, marks the coming of summer.

Despite the faintness of its stars, Aries has assumed great importance in astronomy, because 2000 years ago it contained the point where the Sun passed from south to north across the celestial equator each year. This point, the Vernal Equinox, marked the start of the northern hemisphere spring, and from it the celestial coordinate known as right ascension is measured. Because of the slight wobble of the Earth in space known as precession, this point has now moved into Pisces, and in about 400 years time will move into Aquarius. (The dawning of the age of Aquarius?)

To find Aries, look to the north, find Orion, then the bright star Aldebaran, look further to the west (left) to find the Pleiades star cluster (the seven sisters), and look between the Pleiades and the Great Square of Pegasus.

Chart showing Aries as seen about 10.30 pm (NZDT) mid December. 

Aries chart

Constellation Aquarius Constellation Cetus Constellation Eridanus Constellation Orion Constellation Gemini Constellation Taurus Constellation Auriga Constellation Perseus Constellation Triangulum Constellation Pegasus Constellation Andromeda Constellation Pisces

Some stars in the Constellation

α Arietis (Hamal, from the Arabic for sheep) is a yellow giant star of magnitude 2.0, 66 light years away.

β Ari (Sheratan, the sign) is a white star 60 years away

γ Ari (Mesarthim) is a striking double star 204 light years away at magnitude 2.8. This double star was the first to be discovered, by Robert Hooke in 1664. The stars dominate a field well sprinkled with scattered stars

ε Ari is a challenging double star for larger aperture telescopes. High magnification reveals a tight pair of white stars of magnitudes 5.3 and 5.6. The pair lie 293 light years away.

λ Ari is a white star, magnitude 4.8, 133 light years away with a yellow 7th magnitude companion, easily visible in small telescopes or even good binoculars.

π Ari is a blue-white star of magnitude 5.2, with a close magnitude 8.3 companion, difficult to distinguish in small telescopes. They lie 600 light years away.

Visibility

Aries is north of the equator so fairly low for New Zealand observers. This particularly applies to the brighter stars, Hamal amd Sheraton, which are above the horizon for about 9 hours. The constellation is due north at about 10.30 pm (NZDT) in the middle of December. By the end of January, Hamal is low to the north-west at 10.30 pm.

CORONA AUSTRALIS, pronounced koh-ROH-nah ass-TRAY-liss,
TELESCOPIUM, pronounced TEL-ah SKOH-pee-um,
ARA, pronounced AY-rah

Chart showing the constellations.

Corona Australis, the Southern Crown, was included in Ptolemy's 48 constellations, and assigned 13 stars. In one legend it is said to represent the crown worn by the centaur Sagittarius - a nearby grouping of stars. Although faint, it is a noticeable figure, situated on the edge of the Milky Way.

Telescopium, the Telescope, was originally Tuba Astronomicus, and invented by the Frenchman Lacaille, to honour the important instrument. It is a faint and contrived constellation, but its three principal stars form with θ Ara a small quadrilateral immediately south of Corona Australis. This is in the extreme north-west corner, with the rest of the constellation containing only insignificant stars.

Ara, the Altar, appears amongst the 48 constellations of Ptolemy as the tripod censer, having seven stars. This relatively faint and little known constellation, sometimes visualised as the altar on which Centaurus the Centaur, was about to sacrifice Lupus, the Wolf, or the Altar of the Gods, lies immediately south of Scorpius' tail. The Milky Way is rich and bright in this region, and is in places obscured by dark nebulae.

To find these constellations, look high in the north evening sky to find the tail of Scorpius. The Southern Crown should be readily apparent, especially away from City lights.

Chart showing the Constellations.  Corona passes overhead from NZ mid evening during August

Corona Australis, Telescopium and Ara. 11.3 kb

Ophiuchus & Serpens Constellation Scorpius Constellation Lupus Constellation Norma Constellation Centaurus Constellation Circinus Triangulum Australe Constellation Apus Constellation Octans Constellation Pavo Constellation Tucana Constellation Indus Constellation Scutum Constellation Sagittarius

Some stars and interesting objects in the Constellations

Corona Australis

α Corona Australis is a white star, magnitude 4.1 and 100 light years away.

β CrA is a magnitude 4.1 yellow giant star 110 light years away.

γ CrA is a double star with a period of 122 years. The pair of 5th magnitude yellow stars are currently near their minimum separation and a telescope with greater than 100 mm aperture is needed to split the stars.

κ CrA is a pair of 6th magnitude blue-white stars easily seen in small telescopes. The pair lie about 460 light years away.

NGC 6541 is a 6th magnitude globular cluster about 25,000 light years away, visible in binoculars or small telescopes. Its well condensed appearance in its starry field is most beautiful.

Telescopium

α Telescopii is a magnitude 3.5 blue-white star 590 light years away.

δ Tel consists of two blue-white stars of magnitudes 5.0 and 5.1 visible separately in binoculars and telescopes. They are unrelated stars, being at 590 and 720 light years away.

ε Tel is a magnitude 4.5 yellow giant star 190 light years away.

ζ Tel is a magnitude 4.1 yellow giant star 170 light years away.

NGC 6584 is a conspicuous but not bright globular cluster, visible easily as a faint haze in small telescopes.

Ara

α Arae is a blue-white star magnitude 3.0, lying about 220 light years away.

β Ara is a magnitude 2.9 yellow supergiant star 780 light years away.

γ Ara is magnitude 3.3 blue-white giant star 1100 light years away.

δ Ara is magnitude 3.6 blue-white star 150 light years away.

ζ Arae is a magnitude 3.1 orange giant star 140 light years away.

NGC 6193 is a bright open cluster of about 30 stars, A wide field telescope well shows the remarkable curved chains and lobes of stars, with a small group near the centre. Associated with the cluster is the emission nebula NGC 6188. This needs a clear, dark night and good aperture. An OIII filter helps.

NGC 6397 is a large and bright globular cluster easily visible with binoculars or a small telescope. It has a well condensed centre; there are orange stars in it, and some of the outliers are in arcs and sprays. It is one of the best clusters for small telescopes, and faintly visible to the unaided eye in a dark sky. The cluster is one of the nearest to the Sun at about 7000 light years.

Visibility

Corona Australis passes almost directly overhead as seen from New Zealand. At the beginning of August it is highest in the sky about 11pm, by 10pm mid August and 9pm at the end of August. Telescopium is to the south of Corona Australis, that is towards the pole, while Ara is to the west of Telescopium. Both the latter constellations are circumpolar from the south of New Zealand, that is they never set, while Corona Australis only sets for 3 or 4 hours.