The planetoidsalso known as asteroids, minor bodies either minor planetoidsare pieces of rock and metal that orbit the Sun in the asteroid belt between Mars and Jupiter, as well as elsewhere in the solar system.
Currently, more than 800,000 planetoids in our solar system, and more are discovered every day thanks to advances in technology. Although most are small and pose no danger to Earth, some of the largest ones can be potentially dangerous in the event of an impact.
Among the most famous planetoids are Ceresthe largest in the asteroid belt, Vestaone of the brightest, and Eroswhich was visited by the NEAR Shoemaker spacecraft in 2001.
Many planetoids have also been designated as potentially dangerous objects due to its size and its trajectory close to Earth. Scientists continue to study these objects and look for ways to protect our planet from a possible collision.
How many planets and planetoids are there in the solar system?
The solar system It is made up of a wide variety of celestial objects, such as planets, asteroids, comets and other celestial bodies. However, over time, the number of planets has been the subject of intense debate among scientists.
Traditionally, there were nine planets in the solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. However, in 2006, the International Astronomical Union decided to reclassify Pluto as a planetoid or dwarf planet, which reduced the number of planets in the solar system to eight. In turn, another celestial object known as Eris, discovered in 2005, was also considered a planetoid and not a ninth planet.
ThereforeCurrently, according to the definition of the International Astronomical Union, there are eight planets in the solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. It should be noted that these planets are large celestial bodies that orbit the Sun and have cleared their orbit of other objects. On the other hand, there are also numerous planetoids in the solar system, which are objects smaller than planets and that have not met the criteria to be considered as such.
In summaryAlthough the number of planets in the solar system has been the subject of controversy, there are currently considered to be eight planets and several planetoids. Importantly, these celestial bodies are fundamental to understanding how our solar system formed and evolved.
What planet is considered a planetoid?
A planetoid It is a type of celestial body found in our solar system and, although it has planetary characteristics, it is not considered a complete planet.
In particular, the planet that is considered a planetoid is Pluto. Previously, Pluto was considered the ninth planet in our solar system, but in 2006 the definition of a planet was redefined and Pluto was demoted to planetoid status.
The planets They are defined as celestial bodies that have enough mass that their own gravity makes them spherical, that orbit the sun, and that have cleared the vicinity of their orbit from other bodies. Pluto meets the first two conditions, but not the third, since it shares its orbit with other bodies such as so-called «trans-Neptunian objects.»
Although Pluto is a planetoid By definition, it remains a fascinating and important object in our solar system. It was discovered in 1930 and there is still much to learn about it. For example, it is believed that beneath its ice-covered surface is an underground ocean of liquid water.
What other name do planetoids receive?
The planetoids, also called minor bodies of the solar system, are objects that orbit the Sun, but they are neither planets nor comets. Its name may vary depending on the place in the world or its size.
In English, they are commonly known as asteroidsalthough this term also refers specifically to planetoids found primarily in the asteroid belt between Mars and Jupiter.
For their part, the smallest planetoids, with diameters of less than 1 kilometer, are called meteoroidswhile those that measure more than 1 kilometer and have a triaxial classification are called spherical planetoids.
Today, it is estimated that there are millions of planetoids in the solar system, many of which have not yet been discovered. While these objects may be small and seemingly insignificant compared to the planets in our solar system, they have great scientific value and can provide valuable information about the formation and evolution of the universe.
What are the 6 dwarf planets?
The dwarf planets They are celestial bodies that orbit around the Sun and whose size is smaller than that of a planet. According to the definition established in 2006 by the International Astronomical Union (UAI), there are 6 dwarf planets in our solar system.
The first of them is Pluto, discovered in 1930 by Clyde Tombaugh and considered until 2006 as the ninth planet in the solar system. It is located in the Kuiper belt, an area of the solar system beyond Neptune.
Another of the dwarf planets is Ceres, the largest object in the asteroid belt between Mars and Jupiter. It was discovered in 1801 by Giuseppe Piazzi and has a mass that represents one third of the total mass of the asteroid belt.
The third dwarf planet is Haumea, named after the Hawaiian goddess of fertility. This dwarf planet is characterized by having an ellipsoidal shape due to its rapid rotation, of only 3.9 hours. It was discovered in 2004 by a team of Spanish astronomers led by José Luis Ortiz Moreno.
Another of the dwarf planets is Makemake, discovered in 2005 by a team led by Michael Brown in California. It is located in the Kuiper belt and its size is similar to that of Pluto.
Eris It is another of the dwarf planets in the solar system discovered in 2005. It is the most distant known object in the solar system, and its size is larger than that of Pluto. It was precisely its discovery that led the IAU to reconsider the definition of a planet.
Finally, makemake It is one of the largest and brightest dwarf planets in the Kuiper belt. It was discovered in 2005 by a team led by Michael Brown and is the third most luminous object in the Kuiper belt after Pluto and Varuna.