Fifth planet (hypothetical) Fifth planet (hypothetical) In the history of astronomy, a handful of Solar System bodies have been counted as the fifth planet from the Sun. Under the present definition of a planet, Jupiter is counted as the fifth. There are three main ideas regarding hypothetical planets between Mars and Jupiter. During the early 19th century, as asteroids were discovered, they were considered planets. Jupiter became the sixth planet with the discovery of Ceres in 1801. Soon, three more asteroids, Pallas (1802), Juno (1804), and Vesta (1807) were discovered. They were counted as separate planets, despite the fact that they shared an
Sixth Party System Sixth Party System Experts have debated whether national politics in the United States of America is in the era of a Sixth Party System, or whether the Fifth Party System continues in some form to the present. Opinions also differ on when a Sixth Party System may have begun, with suggested dates ranging from the 1960s to the 1990s. Maisel and Brewer (2011) argue that the consensus among specialists is that the Sixth System is underway based on American electoral politics since the 1960s: The perceived Sixth Party System is characterized by an electoral shift from the electoral coalitions of