Though often get graphical representations of what an exoplanet that has been discovered might look like, in reality they are statistical wobbles.
And
a new study finds that of the some 5,000 planets detected outside our solar system, three are likely not planets, but stars. The new analysis of the data finds that Kepler-854b, Kepler-840b, and Kepler-699b are probably between two and four times the size of Jupiter. So they are likely small stars instead.