What is T Tauri star, bipolar outflow?

A T Tauri star is a young star of less than about two solar masses that has shed its envelope and become visible but has not yet reached the main sequence: it shines by contraction, varies in brightness, and is usually surrounded by a disc from which it still accretes. A bipolar outflow is a pair of fast jets or winds of gas ejected by a young star in opposite directions along the rotation axis of its disc.