Search results
Results from the WOW.Com Content Network
Pluto has roughly one-sixth the mass of the Moon, and one-third its volume. Pluto has a moderately eccentric and inclined orbit, ranging from 30 to 49 astronomical units (4.5 to 7.3 billion kilometres; 2.8 to 4.6 billion miles) from the Sun. Light from the Sun takes 5.5 hours to reach Pluto at its orbital distance of 39.5 AU (5.91 billion km; 3 ...
Only one of them – Pluto – has been observed in enough detail to verify that its current shape fits what would be expected from hydrostatic equilibrium. [53] Ceres is close to equilibrium, but some gravitational anomalies remain unexplained. [54] Eris is generally assumed to be a dwarf planet because it is more massive than Pluto.
Pluto is so small and so remote from the Sun and the Earth that it was not discovered until 1930. [3] It was classified as a planet at the time and remained as such for 76 years until 2006, when the International Astronomical Union reclassified it as a dwarf planet, as it belongs to a belt of many similar small objects. [4]
Pluto was considered a planet up until 2006, when researchers at the International Astronomical Union voted to "demote" it to dwarf planet.
The search for these led to the discovery of Pluto in February 1930, which was too small to explain the discrepancies. Revised estimates of Neptune's mass from the Voyager 2 flyby in 1989 showed that the problem was spurious. [9] Pluto was easiest to find because it has the highest apparent magnitude of all known
For 76 years, Pluto was considered out solar system's ninth planet. So what caused it to lose its planetary status? Find out on this episode of "Space, Down to Earth"!
For the small outer irregular moons of Uranus, such as Sycorax, which were not discovered by the Voyager 2 flyby, even different NASA web pages, such as the National Space Science Data Center [6] and JPL Solar System Dynamics, [5] give somewhat contradictory size and albedo estimates depending on which research paper is being cited.
It is about half the diameter and an eighth the mass of Pluto, a dwarf planet that resides in a frigid region of the outer Solar System called the Kuiper Belt, beyond the most distant planet Neptune.