Costellazione Giraffa, stelle principali e mitologia

OSR blog post

La Giraffa, chiamata in latino Camelopardalis è una costellazione debole dell'emisfero nord, posizionata tra l'Auriga e la Stella Polare, l'Orsa Maggiore e Cassiopea. Si tratta di un vero e proprio "buco nel cielo" data la sua posizione. Le dimensioni della costellazione sono molto estese, infatti la regione del cielo dove è situata corrisponde a circa 757 gradi quadrati. Per questo è considerata come una "costellazione circumpolare". Cosa significa questa definizione? Si tratta di costellazioni visibili tutto l'anno, solo posizionandosi intorno al Polo Nord Celeste.

Giraffe constellation, main stars and mythology

The constellation Giraffe contains only eight brighter stars, positioned in the fifth magnitude. For this reason it will be difficult to recognize while observing the sky. The constellation is counted among the eighty-eight modern constellations.

History has it that the constellation Giraffe was discovered by Kepler’s son-in-law, Jacob Bartsch , way back in 1624. It was he who composed a planisphere where various constellations were mentioned, including that of the Giraffe, together with the Dove of Noe, Rhombus, Unicorn, Moscow, Tiger, Rooster and Jordan. Others claim that its roots are to be found even further back in time and that its true discoverer was Patrus Plancius. However, let’s try to outline its main characteristics.

The main stars of the Giraffe

The main star of the Giraffe is Beta Camelopardalis . Considered as the brightest star, it stands out for its color and is called a yellow supergiant. This is a double star that has components of magnitudes 4.0 and 8.6. Its colors range from yellow to blue. Its location is located at a distance of about a thousand light years from Earth.

There are only four other stars visible to the naked eye that do not exceed magnitude class four. While for all those that belong to magnitude five and six, it is not possible to verify their position, except with appropriate technical means, such as professional telescopes.

A noteworthy asterism present in the constellation of Giraffe is Kemble Falls . Located in the southern part of the constellation, a few degrees north of the Perseus Double Cluster and in the open cluster of NGC 1502. This phenomenon was seen by Kemble in the 1980s. It was described as a real cascade of stars of different colors, easily viewable with small binoculars. These are stars oriented and aligned but not united with each other. In fact, perspective is capable of creating this very particular effect. In Kemble Falls, we find its main star HD 24479 with a magnitude of 4.95 with a characteristic blue color. All the other stars that follow you are at least twenty and their magnitude is between the eighth and seventh magnitude. These have a variety of colors ranging from red to white.

CS Camelopardalis is a supergiant instead, of a variable blue color whose magnitude is greater than the star described previously. In fact, it is a distance of over 4000 light years with magnitude 4.21. This is located on the outside of our spiral arm. While Alfa Camelopardalis is a blue super giant which is about 7000 light years away, located in the Perseus arm and has a magnitude of 4.26.

Eclipsing variable stars are also called eclipsing binaries. This definition is used to indicate the phenomenon of eclipse which makes the star variable. La Giraffa presents the star SV Camelopardalis in this category . It is a spectroscopic binary star capable of oscillating between the ninth and eighth magnitude.

Mythology: Canaan and Isaac

The constellation Giraffe is a recent discovery. It has its roots in 1600 and for this reason, it was not possible to attribute a history of Greek mythology since in addition to not remembering any ancient anecdote, its little visibility to the naked eye did not stimulate any type of comparison. It is said to take its name from a biblical episode featuring Rebecca and Isaac. It is said that in ancient times, Rebecca used a giraffe to reach Canaan and marry Isaac. Others say that it was not a giraffe but a camel that brought Rebecca to Canaan. Except that the constellation doesn’t resemble either animal, unless you have a vivid imagination.

Another curiosity about its history is that its origin cannot be attributed to the Western world but to the Eastern one. In fact, the Constellation of the Giraffe seems to have been discovered by Chinese astronomers long before the seventeenth century. These had created seven different asterisms, with unusual names such as: State Umbrella, Great Minister, Great Guard, Minor Guard, Unashamed Virtue, Four Official Supporters of the Throne.

How to observe the Giraffe constellation

Camelopardalis which in Italian translates to giraffe, can only be traced in its bright stars in opposition to the sun, towards the end of November. These will have to position themselves near the zenith following the south direction, at midnight. If you want to view the constellation in May however, you will need to know that it will be positioned low on the northern horizon.

This is a constellation that only experts can visualize easily, so by equipping ourselves with professional tools, it is possible to go even beyond the limit of observability, so as to be able to witness a fantastic show.