![Light-curve-exoplanet](https://www.astronomy.com/wp-content/uploads/sites/2/2023/02/Light-curve-exoplanet.jpg)
The light curve of an exoplanet transiting its star (top) is different from that of a starspot traversing a star’s disk, so astronomers can tell the two signals apart. Astronomy: Roen Kelly
Thus we can distinguish a transit by the short duration of the dip. … so the dip of a transit is slightly “U-shaped.” The shape of the starspot dip has gentle sides and looks more “V-shaped.”