Final answer:
The T Tauri phase of a protostar is characterized by strong spectral emission lines and is marked by ejected material that can lead to the creation of Herbig-Haro objects.
Step-by-step explanation:
The T Tauri phase of a protostar is characterized by strong spectral emission lines. The T Tauri stars are young stars in their early development and are observed in the infrared region of the spectrum. They display outflows and jets, which include material such as protons and electrons ejected at high speeds, and these processes contribute to the T Tauri wind. The high-energy interaction of these jets with the surrounding interstellar material can lead to the formation of Herbig-Haro (H-H) objects, which are observable as bright patches in space, often in the regions of star formation like the Orion or Taurus constellations. These objects signify where the jet material is colliding with the interstellar medium, causing it to glow due to the energy of the impact.