Once in a while the planets are arranged such that they are spread across the sky as they look in this graphic. However over time, several days, this arrangement changes as the planets continue moving along their orbits.
The planets are not lined up in a straight line outward from the Sun but rather are arranged along the ecliptic. The ecliptic is the Earth’s orbital path around the Sun and the respective orbit of each planet is inclined from the ecliptic. And this is one of those times when it is easy to visualize the ecliptic. Click here to read a previous posting about the ecliptic and planet inclination.
This animated graphic is showing the terrestrial planets as they move along their respective orbits for this month. They are not ‘lined up’ as they appear to be in the above horizon picture.