"Rare Planetary Alignment: When Have All 8 Planets Ever Aligned?"

The eight planets in the solar system have never truly aligned in a straight line in 3D space due to their tilted orbits. While they may appear to line up from Earth, this is more about visual appearance than physical alignment. The last time the eight planets were grouped within 30 degrees was Jan. 1, 1665, and the next time will be March 20, 2673. Planetary alignments have virtually no significant physical effects on Earth, and the gravitational force changes during an alignment are negligible.