The Orbital Properties, Internal Motions, and Origins of the 120-Myr-old Pisces-Eridanus Stellar Stream

Gaia DR2 has recently revealed the nearby 120 Myr old Pisces-Eridanus (Psc-Eri) stellar stream orbiting the Milky Way. Studying stellar streams similar to Psc-Eri can help us understand the evolution of the Galaxy and the nature of star formation. In this work, we use Gaia astrometric data to perform orbit integration of the stream members throughout its formation (t=-100Myr to t=500Myr) using the python package galpy. We also created 3-dimensional quiver plots of its structure at multiple time periods to understand the internal kinematics of the system and determine its morphology at birth. The preliminary results of its structure at birth address the current debate of whether the stream formed as a spherical or cylindrical cluster.