Draco - Downloadable article
The celestial dragon guards a treasure of galaxies and double stars.
March 3, 2009
|This downloadable article is from an Astronomy magazine 45-article series called "Celestial Portraits." The collection highlights all 88 constellations in the sky and explains how to observe each constellation's deep-sky targets. The articles feature star charts, stunning pictures, and constellation mythology. We've put together 11 digital packages. Each one contains four Celestial Portraits articles for you to purchase and download.|
"Draco" is one of four articles included in Celestial Portraits Package 3.
It is difficult to observe the constellation Draco the Dragon in one season. The tail end of Draco slithers between the Big Dipper and Little Dipper, which are frequent spring observing targets. Draco's midsection reaches an area north of Cepheus that is overhead on autumn evenings. This winding constellation finally tops off above the summer constellations of Hercules and Cygnus. All told, Draco's string of stars wraps halfway around the North Celestial Pole.
The most recognizable asterism in Draco is a four-star trapezoid north of the Keystone of Hercules that defines the head of the dragon. Draco's brightest star is Eltanin (Gamma [γ] Draconis), an orange, spectral type K star of 2nd magnitude, 150 light-years distant, which burns as brightly as 180 suns. Another star in the constellation brighter than 3rd magnitude is Rastaban (Beta [β] Draconis), which also composes part of the dragon's head. The Alpha (α) designation of Draco goes to Thuban, a rather unimposing star that can be found between the bowl of the Little Dipper and the handle of the Big Dipper. Thuban's notoriety lies in its distinction as a former pole star; 4,800 years ago, the wobble of Earth's axis put Thuban within 10' of the North Celestial Pole. To read the complete article, purchase and download Celestial Portraits Package 3.
|Deep-sky objects in Draco|
NGC 3147, NGC 3735, NGC 4125, NGC 4236, NGC 4319, NGC 4589, M102, NGC 5905, NGC 5907, NGC 5985, NGC 6015, Mu Draconis, UGC 10822, Nu Draconis, NGC 6503, NGC 6543 (Cat's Eye Nebula), Chi Draconis, NGC 6742