Untangling the Galaxy. II. Structure within 3kpc

The current paper builds on the sample from the previous work, extending it in distance from 1 to 3kpc and increasing the number of identified structures up to 8292. To aid in the analysis of the population properties, we developed a neural network called Auriga to robustly estimate the age, extinction, and distance of a stellar group based on the input photometry and parallaxes of the individual members.

We apply Auriga to derive the properties of not only the structures found in this paper, but also previously identified open clusters. Through this work, we examine the temporal structure of the spiral arms. Specifically, we find that the Sagittarius Arm has moved by >500pc in the last 100Myr and the Perseus Arm has been experiencing a relative lull in star formation activity over the last 25Myr.