Draco is a constellation in the far northern sky. Its name is Latin for dragon. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and remains one of the 88 modern constellations today. The north pole of the ecliptic is in Draco. Draco is circumpolar, and can be seen all year from northern latitudes.
Sigma Draconis, also named Alsafi, is a 4.7-magnitude star located at a distance of 18.8 light-years from the Sun in the constellation of Draco.
Beta Draconis, a name Latinized from β Draconis, is a binary star system and the third-brightest star in the northern circumpolar constellation of Draco. The two components are designated Beta Draconis A and B respectively. With a combined apparent visual magnitude of 2.79, it is bright enough to be easily seen with the naked eye. Based upon parallax measurements from the Hipparcos astrometry satellite, it lies at a distance of about 380 light-years from the Sun. The system is drifting closer with a radial velocity of −21 km/s.
BY Draconis variables are variable stars of late spectral types, usually K or M, and typically belong to the main sequence. The name comes from the archetype for this category of variable star system, BY Draconis. They exhibit variations in their luminosity due to rotation of the star coupled with starspots, and other chromospheric activity. Resultant brightness fluctuations are generally less than 0.5 magnitudes. Light curves of BY Draconis variables are quasiperiodic. The period is close to the star's mean rotational rate. The light curve is irregular over the duration of the period and it changes slightly in shape from one period to the next. For the star BY Draconis the shape of the light curve over a period remained similar for a month.
Epsilon Draconis, Latinized from ε Draconis, is a fourth-magnitude star in the constellation Draco. This star along with Delta Draconis (Altais), Pi Draconis and Rho Draconis forms an asterism known as Al Tāis, meaning "the Goat".
Iota Draconis, also named Edasich, is a star in the northern circumpolar constellation of Draco. A visually unremarkable star of apparent magnitude 3.3, in 2002 it was discovered to have a planet orbiting it. From parallax measurements, this star is located at a distance of about 101.2 light-years from the Sun.
Psi¹ Draconis, also designated 31 Draconis, is a triple star system in the northern constellation of Draco. The system is fairly close, and is located about 75 light-years from the Sun, based on its parallax.
Hyalurga is a genus of tiger moths in the family Erebidae. The genus was erected by Jacob Hübner in 1819.
Virbia is a genus of tiger moths in the family Erebidae. The genus was erected by Francis Walker in 1854.
Euspira is a genus of medium-sized sea snails, marine gastropod molluscs in the subfamily Polinicinae of the family Naticidae, the moon snails.
Ephialtias is a genus of moths of the family Notodontidae. It consists of the following species:
Ephialtias choba is a moth of the family Notodontidae first described by Herbert Druce in 1899. It is found in the lower Amazon of Brazil.
Josia gigantea is a moth of the family Notodontidae first described by Herbert Druce in 1885. It is found from southern Mexico to Colombia.
Lyces is a genus of moths of the family Notodontidae erected by Francis Walker in 1854. It consists of the following species:
Nebulosa is a genus of moths of the family Notodontidae. It consists of the following species:
Dioptis is a genus of moths of the family Notodontidae. It consists of the following species:
Erbessa is a genus of moths of the family Notodontidae. It consists of the following species:
Polypoetes is a genus of moths of the family Notodontidae. It consists of the following species:
Theta Draconis, a name Latinized from θ Draconis, is a binary star system in the northern circumpolar constellation of Draco. It is faintly visible to the naked eye at night with an apparent visual magnitude of 4.12. Parallax measurements place it at an estimated distance of 68.6 light-years from the Sun, and it is drifting closer with a radial velocity of −8 km/s. It has a relatively high proper motion, traversing the celestial sphere at the rate of 0.464″ per year. O. J. Eggen included this star as a member of the NGC 1901 supercluster based on its space motion.
Omega Draconis, Latinized from ω Draconis and also known as 28 Draconis, is a binary star in the constellation of Draco. The system is fairly close, and is located about 76 light-years away, based on its parallax.
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