Tag Archives: Big Dipper

Canes Venatici (The hunting dogs)

Canes VenaticiCanes Venatici represents the hunting dogs of Bootes, the herdsman. This is a small northern constellation consisting of only two main stars, and it is located below the Big Dipper’s curved handle and to the right of Bootes. Canes Venatici reaches its highest nightfall ascension in May.

In spite of its small size, Canes Venatici is very interesting in its arrangement of galaxies. The Giant Void, the largest galactic supervoid known, exists along side several other notable galaxies. There are four Messier galaxies: M51 (the Whirlpool Galaxy), M63 (the Sunflower Galaxy), M94, and M106. A fifth Messier object in the M3 globular star cluster, which is bright enough to be seen with the unaided eye under a very dark sky.
http://en.wikipedia.org/wiki/Canes_Venatici

IAU Canes Venatici chart, IAU and Sky & Telescope magazine (Roger Sinnott & Rick Fienberg), June 4, 2011.
IAU Canes Venatici chart, IAU and Sky & Telescope magazine (Roger Sinnott & Rick Fienberg), June 4, 2011.

© James R. Johnson, 2014.
jim@jrjohnson.net

Lynx (The lynx)

This faint, northern circumpolar constellation is best seen in March. It is so named because lynx-like vision is required to see its faint stars. Also, it represents the long, stretched out body of a lynx. This 28th-largest constellation is located between the Big Dipper, Pollux and Castor of Gemini, and Auriga.  Its only named star is Alsciaukat, which is Arabic for thorn. This constellation’s most notable deep sky object, the Intergalactic Tramp (NGC 2419), is the globular cluster of stars most distant from Earth. The Lynx reaches its highest nightfall ascension in March.
http://en.wikipedia.org/wiki/Lynx_(constellation)

IAU Lynx chart, IAU and Sky & Telescope magazine (Roger Sinnott and Rick Fienberg), June 5, 2011.

© James R. Johnson, 2014.
jim@jrjohnson.net

Camelopardalis (The giraffe)

Camelopardalis, Till Credner, July 16, 2004.The Greek camelopardalis means giraffe, which comes from camel because of its long neck and leopard because of its spots.  The brightest star in this constellation is 4th magnitude, which can be a challenge to see in a light-polluted urban sky. This is a faint northern constellation that provides the foreground stars in a direction that points away from the flat disk of the Milky Way. This 18th-largest constellation is found between Polaris, The Big Dipper and Cassiopeia, and is best viewed in February when it is high overhead at nightfall. Camelopardalis is also the direction in which Voyager I is headed, but its power source will be long dead when it arrives in that vicinity thousands of years from now. This constellation is also home to May’s Camelopardalids meteor shower.
http://en.wikipedia.org/wiki/Camelopardalis

IAU Camelopardalis chart, IAU and Sky & Telescope magazine (Roger Sinnott and Rick Fienberg), June 5, 2011.

© James R. Johnson, 2014.
jim@jrjohnson.net

Cassiopeia (A Greek mythological queen)

CassiopeiaCassiopeia is named after the vain Greek mythological queen of Aethiopia, the wife of Cepheus and the daughter of Andromeda. This constellation was one of the 48 constellations cataloged by the 2nd century astronomer Ptolemy that remain among the 88 modern constellations. This 25th-largest constellation appears as either a distinct “M” (fall and winter) or “W” (spring and summer) shaped asterism of bright stars that often catches the eye of novice observers who happen to gaze in the right direction. Although it is a northern circumpolar constellation that can be seen year round, it is found high above Polaris in December, which is when it is most easily viewed. This constellation is located opposite of the Big Dipper from Polaris, so try finding it by starting at the Big Dipper, and tracing a line northward (upward) through Polaris until reaching the first grouping of bright stars.

The Milky Way flows through Cassiopeia, and it contains two Messier objects, M52 and M103, both of which are open star clusters. It also contains numerous other NGC objects and two supernova remnants, including Tycho’s Star, a supernova recorded in 1572 by Tycho Brahe, and another remnant of a supernova that was seen 300 years ago. Interestingly, if our sun were observed from Alpha Centuari, our nearest solar neighbor 4 light-years away, it would appear to be located in Cassiopeia.
http://en.wikipedia.org/wiki/Cassiopeia_(constellation)

603px-Cassiopeia_IAU.svg
IAU Cassiopeia chart, IAU and Sky & Telescope magazine (Roger Sinnott and Rick Fienberg), June 4, 2011.

© James R. Johnson, 2014
jim@jrjohnson.net

Draco (The dragon)

Draco, Ursa MinorDraco is a large constellation of rather dim stars that is also one of the 48 constellations cataloged by 2nd century astronomer Ptolemy. Since it is a circumpolar constellation at 40 degrees north latitude, it is visible on any night at any time, but it reaches its highest nightfall ascension in January. Draco’s tail starts near the northernmost pointer star of the Big Dipper, and it roughly parallels the curvature of the Big Dipper handle before curving under the Little Dipper and turning back toward the south, and then terminating at the dragon’s head. The best chance of seeing this constellation will be under a very dark sky.

Thuban (Alpha Draconis), is the most interesting star in Draco. Six thousand years ago, when the Egyptian pyramids were build, Thuban was the Earth’s pole, or north star, and the Egyptians built north-facing entrances on the pyramids that were aligned to this star. Due to precession, the large circle that the Earth’s axis traces among the fixed stars every 26,000 years, Polaris has temporarily supplanted Thuban as the pole star. The most notable deep sky object in this constellation is the Cat’s Eye Nebula (NGC 4563).
http://en.wikipedia.org/wiki/Draco_(constellation)

IAU Draco Chart, IAU and Sky $ Telescope (Roger Sinnott and Rick Fienberg), June 5, 2011.
IAU Draco chart, IAU and Sky & Telescope magazine (Roger Sinnott and Rick Fienberg), June 5, 2011.

© James R. Johnson, 2014.
jim@jrjohnson.net

Virgo (The virgin)

Constellation VirgoVirgo, the virgin, is one of the zodiacal constellations,  is one of the 48 constellations cataloged by 2nd century astronomer Ptolemy, and is the 2nd largest constellation in the sky. It can be found at is highest point in the sky at nightfall in March. Virgo is located on the ecliptic, flanked by Leo and Libra. It can also be found by following the arc of the Big Dipper’s handle through Arcturus in Bootes to Spica (Alpha Virginis), Virgo’s brightest star. Some of Virgo’s remaining stars can be difficult to see in light-polluted urban skies because this is not a particularly bright constellation. Within Virgo is one of the two points where the ecliptic intersects the celestial equator.  The moment of the Sun’s southward crossing of the celestial equator as it moves along the ecliptic is the Autumnal Equinox, which marks the first day of Fall.

The Virgo Cluster is a very large scale object spanning about eight degrees and containing 1,300 or more individual galaxies. The cluster is centered in Virgo, and extends northward into Coma Berenices. The member galaxies that were cataloged by Charles Messier are M49, M58, M59, M60, M61, M84, M86, M87, M89, and M90. Many other galaxies in this cluster have NGC designations. The Sombrero Galaxy, M104, is a very unusual galaxy in Virgo that is not a member of the Virgo Cluster.
http://en.wikipedia.org/wiki/Virgo_(constellation)

IAU Virgo chart, Sky & Telescope magazine (Roger Sinnott and Rick Fienberg), June 5, 2011.
IAU Virgo chart, Sky & Telescope magazine (Roger Sinnott and Rick Fienberg), June 5, 2011.

© James R. Johnson, 2014.

Boötes (The herdsman or plowman)

BootesBoötes is a bright and distinct northern constellation that is one of the 48 constellations cataloged by 2nd century astronomer Ptolemy. It can be found by looking south of Draco, lying between Hercules and Ursa Major. It is also found by following the curve of the Big Dipper’s handle southward and away from the bowl to the bright star Arcturus. Sometimes the phrase “arc to Arcturus” is used to describe this approach to locating it. Boötes reaches its highest nightfall ascension in June. Arcturus is the fourth brightest star in the night sky, and Boötes is home to many other bright stars, including eight above the fourth magnitude and an additional 21 above the fifth magnitude, making a total of 29 stars easily visible to the naked eye.

There are no Messier objects located in Boötes, but several NGC galaxies can be found with a telescope. The radiant of the Quadrantids meteor shower, which displays about 100 meteors per hour when it peaks over January 3rd and 4th, is located between Bootes’ head and the end of Ursa Major’s tail.
http://en.wikipedia.org/wiki/Bootes_(constellation)

IAU Bootes chart, IAU and Sky  Telescope magazine (Roger Sinnott and Rick fienberg), June 4, 2011.

IAU Bootes chart, IAU and Sky & Telescope magazine (Roger Sinnott and Rick Fienberg), June 4, 2011.

© James R. Johnson, 2014.
jim@jrjohnson.net

Leo (The lion)

Constellation LeoLeo, the lion, is a distinctive zodiacal constellation that was cataloged by 2nd century astronomer Ptolemy. It is located on the ecliptic between Cancer and Virgo, and can be found below the bowl of the Big Dipper with both constellations arriving at their highest nightfall ascension in April.  Leo closely resembles a crouching lion with its rather distinct backward question mark, or sickle asterism. This constellation features the bright star Regulus (Alpha Leonis) at the back of the lion’s head.

The most famous deep sky object in Leo is The Leo Triplet is a close grouping of the galaxies M65, M66 (displayed) and NGC3628 that can be seen together in a single telescopic field of view. For those observing with telescopes, there are several other galaxies cataloged by Charles Messier are located in Leo, to include M65, M66, M95, M96 and M105. Leo is also home to the famous Leonids meteor shower that occurs during November, peaking at about 10 meteors per hour on November 14th and 15th.
http://en.wikipedia.org/wiki/Leo_(constellation)

IAU Leo chart, IAU and Sky & Telescope magazine (Roger Sinnott and Rick Fienberg, June 5, 2011.
IAU Leo chart, IAU and Sky & Telescope magazine (Roger Sinnott and Rick Fienberg), June 5, 2011.

© James R. Johnson, 2014.
jim@jrjohnson.net

The Whirlpool Galaxy (M51)

Find The Whirlpool Galaxy (M51) by locating the three handle stars of the Big Dipper. Take a line from the middle star to the end of the handle. Now take a 90-degree turn toward the inside of the handle, just under half the distance between the two stars. Look for a small, diffuse fuzzy blob. Not impressive, even in a larger amateur telescope, but you will have observed your first galaxy! Images of the Whirlpool Galaxy in Wikipedia reveal that it is a spiral, face on galaxy.
http://en.wikipedia.org/wiki/Whirlpool_Galaxy

Ursa Minor (The lesser bear)

320px-UrsaMinorCCSimilar to Ursa Major, which contains the Big Dipper asterism, Ursa Minor contains another recognizable asterism that is often called the Little Dipper. Some of the dimmer dipper stars can be difficult to locate in city skies, and the other stars forming the bear might be impossible to see. Polaris, the constellation’s brightest star, is found at the end of the bear’s tail, or at the end of the dipper handle. This star is thought by some to be significant because it is the brightest star in the sky, which is incorrect – Sirius in Canis Major is actually the brightest star in all of the night sky. An observer can verify that Polaris is not the brightest star in the sky by locating it, and comparing it with other stars in the rest of the sky. Polaris can be located by using the Big Dipper’s pointer stars, the two stars at the end of the dipper bowl away from the handle, and drawing an imaginary line upwards from the top of the bowl.

Ursa Minor is the 56th-largest constellation, and one of the 48 constellations cataloged by the 2nd century astronomer Ptolemy that remain among the 88 modern constellations. There are no Messier objects in this constellation.
http://en.wikipedia.org/wiki/Ursa_Minor_(constellation)

IAU Ursa Minor Chart, IAU and Sky & Telescope magazine (Roger Sinnott and Rick Fienberg), June 5, 2011.

© James R. Johnson, 2014.
jim@jrjohnson.net