三角座星系
Star formation is taking place at a rate that is strongly correlated with the local gas density, and the rate per unit area is higher than in the neighboring Andromeda Galaxy. (The rate of star formation is about 3.4 Gyr−1 pc−2 in the Triangulum Galaxy, compared to 0.74 in Andromeda.) The total integrated rate of star formation in the Triangulum Galaxy is about . It is uncertain whether this net rate is currently decreasing or remaining constant.