To understand the form of the Local arm between the Sagittarius and Perseus arms, the stellar density of a specific population of stars with about 1 Gyr of age between 90° ≤ l ≤ 270° have been mapped using the Gaia DR2. The “spur” interpretation may be incorrect. The Local arm is reasonably referred the fifth feature in the Milky Way. These results reveal that the Local Arm is larger than previously thought, and both its pitch angle and star formation rate are comparable to those of the Galaxy’s major spiral arms. The segment has the length of ~20,000 ly and the width of ~3,000 ly with the pitch angle from 10.1° ± 2.7° to 11.6° ± 1.8°. The accuracy locations of interstellar masers in HMSFRs (high-mass star-forming regions) have been shown that the Local arm appears to be an orphan segment of an arm between the Sagittarius and Perseus arms that wraps around less than a quarter of the Milky Way. Measurement accuracy was better than ☑0% and even 3%, the best parallax measurement in the BeSSeL project ( Bar and Spiral Structure Legacy Survey). Recently, the parallax and proper motion of more than 30 methanol (6.7-GHz) and water (22-GHz) masers in high-mass star-forming regions within a few kiloparsecs of the Sun were measured. Within the arm, the Solar System is close to its inner rim, in a relative cavity in the arm's Interstellar Medium known as the Local Bubble, about halfway along the arm's length, approximately 8,000 parsecs (26,000 light-years) from the Galactic Center. Long thought to be a minor structure, namely a 'spur' between the two arms mentioned, evidence was presented in mid 2013 that the Orion Arm might be a branch of the Perseus Arm, or possibly an independent arm segment. The arm is between the Carina–Sagittarius Arm (the local portions of which are toward the Galactic Center) and the Perseus Arm (the local portion of which is the main outer-most arm and one of two major arms of the galaxy).

Betelgeuse, Rigel, the three stars of Orion's Belt, the Orion Nebula) are within it as shown on the interactive map below. Some of the brightest stars and most famous celestial objects of the constellation (e.g. The arm is named for the Orion Constellation, which is one of the most prominent constellations of Northern Hemisphere winter (Southern Hemisphere summer).

Section 8 arm of orion