<Tr> <Td> pink </Td> <Td> Carina--Sagittarius Arm </Td> </Tr> <Tr> <Td_colspan="2"> There are at least two smaller arms or spurs, including: </Td> </Tr> <Tr> <Td> orange </Td> <Td> Orion--Cygnus Arm (which contains the Sun and Solar System) </Td> </Tr> <P> Two spiral arms, the Scutum--Centaurus arm and the Carina--Sagittarius arm, have tangent points inside the Sun's orbit about the center of the Milky Way . If these arms contain an overdensity of stars compared to the average density of stars in the Galactic disk, it would be detectable by counting the stars near the tangent point . Two surveys of near - infrared light, which is sensitive primarily to red giants and not affected by dust extinction, detected the predicted overabundance in the Scutum--Centaurus arm but not in the Carina--Sagittarius arm: the Scutum - Centaurus Arm contains approximately 30% more red giants than would be expected in the absence of a spiral arm . This observation suggests that the Milky Way possesses only two major stellar arms: the Perseus arm and the Scutum--Centaurus arm . The rest of the arms contain excess gas but not excess old stars . In December 2013, astronomers found that the distribution of young stars and star - forming regions matches the four - arm spiral description of the Milky Way . Thus, the Milky Way appears to have two spiral arms as traced by old stars and four spiral arms as traced by gas and young stars . The explanation for this apparent discrepancy is unclear . </P>

Where is our galaxy located in the milky way