The code below shows a single point on the graph of a function, which is supposed to be located at y=0:

x = np.linspace(-3, +3, 100)
y = np.exp(-x**2) * (2 + np.sin(2*x) + np.sin(5*x))

fig, ax = plt.subplots(figsize=(8, 4))

ax.plot(x, y, linestyle='-', linewidth=2.0, color="black")
ax.scatter(x = 0.90, y = 0, color = "blue")

plt.plot()

What would be the simplest way to put the blue point really on the x-axis? (and not slightly above as it is shown on the plot).
Thanks for any hints on how to proceed.