The spiral arm of our Galaxy that is about 5000 l.y. closer to the centre of the Galaxy than the local Orion Arm, and roughly parallel to it. The Carina Arm may be an extension of this arm. According to recent studies of galactic structure, this is one of the two minor arms of our Galaxy, the other being the Norma Arm. As viewed from Earth, the galactic centre lies behind the Sagittarius Arm and the Scutum–Centaurus and Norma Arms beyond it, but is highly obscured at visible wavelengths by dust in the Galaxy's disk. The Sagittarius Arm can be traced behind the stars of our local arm from Serpens via Scutum to Scorpius, Sagittarius, Centaurus, and Carina. Among the objects it contains are the Eagle Nebula, the Trifid Nebula, the Lagoon Nebula, the Jewel Box cluster, and Eta Carinae.
Subjects: Astronomy and Astrophysics.