Tag Archives: January

Fornax (The furnace)

Constellation FornaxFornax, the furnace, is a southern constellation that barely comes into view for observers at 40-degrees north latitude. It is south of Cetus, and flanked by Eridanus and Sculptor. It reaches its highest point in the sky at nightfall in January, but its dim stars and placement at only ten degrees above the horizon make this a very challenging constellation. The view beyond Fornax’s foreground stars is out of the plane of the Milky Way Galaxy. This accounts for the paucity of visible stars in this region, and is why it was chosen for one of the Hubble Deep Field photographs. This also explains why a relatively large number of the dwarf galaxies in the Milky Way’s galactic halo can be found in this direction with a telescope.
http://en.m.wikipedia.org/wiki/Fornax

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

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

Perseus (A Greek mythological hero)

PerseusCCThe constellation Perseus is located near several other constellations to which Perseus is related in Greek mythology: Cepheus, Andromeda, Pegasus, Cassiopeia, and Cetus. This constellation was one of the 48 constellations cataloged by 2nd century astronomer Ptolemy that remain among the 88 modern constellations. This easily spotted constellation is well placed high in the northern sky and best seen in January. It is found between Cassiopeia and the Pleiades, and Mirfak (Alpha Persei) is its brightest star Its most interesting star Algol (Beta Persei) is an eclipsing binary star. Its variable brightness, which is noticeable to the naked eye, decreases by over one degree of magnitude for about ten hours on a cycle time of just under three days. This star is also known as the Demon Star, because the ancients perceived its variability as an ominous sign. Also notable in this constellation is theNGC869NGC884 Double Cluster (NGC 869 and NGC 884), which are naked eye objects under very dark skies. Perseus is home to two Messier objects, M34 and M76, and to the Perseids meteor shower. This meteor shower, one of the most consistently prominent meteor showers each year, lasts from mid-July to late August, peaking between the 9th and 10th of August.
http://en.wikipedia.org/wiki/Perseus_(constellation)

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

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

Eridanus (The river)

Eridanus was the ancient Greek name for today’s Po River. This constellation was one of the 48 constellations cataloged by the 2nd century astronomer Ptolemy that remain among the 88 modern constellations. This southern constellation has the distinction of being sixth largest of the modern constellations, and is best seen at its highest nightfall ascension in January. The river begins near Orion’s left foot and flows southward from there. At our 40-degree north location, the southern, or lower half of the constellation remains hidden below the horizon. At the southern end of Eridanus is the magnitude 0.5 star Achernar whose traditional name means “the river’s end.”

Of particular interest in this constellation is the Eridanus Supervoid. Numerous galaxies can be seen in deep exposure photographs in almost every direction when looking outward into the Universe beyond the foreground Milky Way stars, but the sky in the direction of Eridanus is almost entirely void of distant galaxies.
http://en.wikipedia.org/wiki/Eridanus_(constellation)

597px-Eridanus_IAU.svg
IAU Eridanus chart, IAU and Sky & Telescope magazine (Roger Sinnott and Rick Fienberg), June 5, 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