Instead, the orbits of the classical planets have various (but small) inclinations with respect to the ecliptic.

During the new moon on December 2-3, 1899, a near-grand conjunction of the classical planets and several other binocular bodies occurred.

The 5 classical planets are associated with the Wu Xing:

That is, they have low-eccentricity and sometimes low-inclination orbits like the classical planets.

During a solar eclipse, an extremely rare grand conjunction of the classical planets occurred, for the first time since 1821.

The Navagraha (deities of the classical planets) are carved above the lintel.

In their initial proposal, the astronomers tried maintaining some sense of order by labeling the Big Eight as "classical planets."

In antiquity the classical planets were the non-fixed objects visible in the sky, known to various ancient cultures.

The seven classical planets are those easily seen with the naked eye, and were thus known to ancient astrologers.

The astrological descriptions attached to the seven classical planets have been preserved since ancient times.