What is a T-Tauri star?
a) a collapsing cloud of gas about to become a protostar
b) a dying star
c) a cool main sequence star
d) a star releasing a planetary nebula
e) a protostar about to become a star
Answer: E) a protostar about to become a star
t-tauri stars often show jets of gas emitted in two direction - "bi-polar flow" suggesting they are not yet stable