The next planetary alignment will not occur until the year 2854. According to astronomers, such alignment typically occurs every 1500 years, with the last phenomenon appearing in 561 B.C.
Speaking of planetary alignment, the term should not be taken to mean that the planets will line up perfectly. That is an occurrence that can never happen due to the unique orbits of the planets. Scientists typically refer to alignment as being the instance where the orbits of the heavenly orbs are all within 30 degrees of each other. When there is a perfect alignment, usually only two or three planets make it to the party.