Draco, the Dragon, is an ancient and sprawling constellation that winds its way through the northern night sky. Its name is derived from the Latin term for “huge serpent,” a form recognized by astronomers for millennia and included in Ptolemy’s original catalog of constellations in the 2nd century. Draco is a circumpolar constellation for most observers in the Northern Hemisphere, meaning it never dips below the horizon. One of its stars, Thuban, is historically significant because it served as the North Star around 2600 B.C., when the ancient Egyptians were constructing the pyramids.
Optimal Viewing Conditions
To find Draco, selecting the best viewing circumstances increases the chance of success, as many of its stars are not exceptionally bright. A truly dark sky is important, requiring observers to get away from the light pollution of cities and towns. The faintness of the stars forming the Dragon’s body means they can easily be washed out by artificial light or a bright moon.
While the constellation is always present in the northern sky, its highest and most prominent position occurs during the summer months. For mid-northern latitudes, the Dragon is best viewed in the evening around July. At this time, it sits highest overhead, offering the clearest view through less of the Earth’s atmosphere. Checking local weather forecasts for a night with clear skies and low humidity provides the most favorable conditions for spotting the constellation’s full shape.
Navigating the Northern Sky Using Guide Stars
The most reliable way to locate Draco is by using the Big Dipper, which is part of the constellation Ursa Major. Locate the Big Dipper’s bowl, then focus on the two stars forming the outer edge, called the “pointer stars,” Dubhe and Merak. Drawing an imaginary line through these two stars and extending it northward leads directly to Polaris, the North Star.
Polaris marks the end of the handle of the Little Dipper (Ursa Minor). Draco’s long, winding body snakes between the Big Dipper and the Little Dipper, wrapping around the North Star. You can trace the Dragon’s tail starting near the Big Dipper and following its curve away from the Little Dipper’s bowl. The tail begins with the star Thuban, positioned almost directly between the two Dippers.
Following the curve of the tail will lead toward the constellation Lyra and the figure of Hercules. This long chain of stars represents the body and tail of the Dragon, extending in a broad arc. The path continues until you reach a distinct star grouping that forms the Dragon’s Head, situated near the border of Hercules. This star-hopping technique provides a clear path from the most recognizable pattern in the northern sky to the Dragon’s figure.
Identifying Draco’s Distinct Shape and Main Stars
Once you have followed the serpentine body between the two Dippers, the final step is to confirm your finding by identifying the Dragon’s head. This head is its most distinct feature, formed by a group of four stars arranged in a noticeable trapezoid or quadrangle shape. This compact grouping is located just north of the constellation Hercules and near the bright star Vega in Lyra.
The two most prominent stars in this trapezoid are Eltanin and Rastaban. Eltanin (Gamma Draconis) is the brightest star in the constellation, shining with an orange tint as an orange giant located about 148 light-years away. Rastaban (Beta Draconis) is a slightly fainter yellow giant star whose traditional name means “head of the serpent.” These two stars often form the eyes of the Dragon in visual representations. Their relative brightness and distinct formation make the Dragon’s Head the easiest part of the constellation to pinpoint after navigating the winding path of its dimmer tail stars.