Pluto at the moment, although it is not a full planet, however, bears the proud title of "dwarf". It has several satellites, including Charon (investigated in 1978), Hydra and Nikta (discovered in 2005), Kerber (2011) and Styx (2012). Who opened this facility and what caused the change in its status?

History of the discovery and name of Pluto

A French mathematician who studied celestial mechanics, Urbain Leverrier, conducted a study of the orbit of Uranus. He revealed certain unrest there, which led to the idea that it was some unknown nearby planet that was their cause. In 1894, the American businessman, astronomer and mathematician Percival Lowell founded the observatory at his own expense. He also initiated the project, which was engaged in the search for the ninth planet. For a long time, the search was unsuccessful - many photographs were taken with numerous celestial bodies, but no one saw the desired planet there.

Pluto was discovered in 1930 on February 18 by the American astronomer Clyde Tombo. Being hired by the observatory, Clyde took photographs and suddenly noticed a moving object in the pictures (a simple animation was made from several photographs), and it was Pluto. The Lowell Observatory on March 13 of the same year made a statement on the discovery of a new planet.

Interesting fact: A spacecraft called New Horizons was launched in 2006 and its mission is to study Pluto. On board is part of the ashes of Clyde Tombo - the man who discovered this celestial body.

Why is Pluto so called?

Of course, after such a grand event in the world of astronomy, as the discovery of a new planet, a new problem arose - what is the name to give it? Such a right was granted to the discoverer. Not to Clyde Tombo himself, but to the place where he worked - Lowell Observatory. Lowell's long-dead wife, Constance, suggested several names. The first name of the planet is Percival, in honor of her husband, then Zeus, and afterwards its own name. However, the scientific community ignored her suggestions.

The current name "Pluto" was coined by Venice Burnie, an ordinary Oxford schoolgirl. The fact is that Pluto is a god from ancient Roman mythology and it was he who ruled the underworld. What could be better for the gloomy, cold and dark world of the planet?

The girl voiced her version to her grandfather, who then worked in the library of Oxford University. He passed on the offer to Professor Turner, who had sent a message to his colleagues in the United States. In total, 3 names were proposed for the planet: “Minerva”, “Kronos” and “Pluto”. The first 2 names were rejected, and officially the planet began to bear the name Pluto 1930 on May 1.

Pluto status now

Initially, in 1930, Pluto was recognized as the planet - the 9th from the Sun, but relatively recently it has lost its status. Scientists began to doubt that Pluto is commensurate with the parameters of the Earth. As a result of research, he was identified as a dwarf planet. On this occasion, a whole debate was held several times. The final decision was made in 2006.Scientists have identified several criteria for determining the status of the planet:

• A cosmic body must orbit around the Sun, and also be a satellite of one of the stars, and not of any planet.
• The object must have such a mass that will allow it to gain the shape of a sphere under the influence of gravity.
• The dimensions of the body should be so large that there are no larger objects within its orbit. An exception can only be its satellites or objects under the influence of gravity.

Thus, after checking all these factors, scientists found that Pluto cannot be called a planet because of the third criterion. Since it is located in the Kuiper belt, its mass was compared with nearby objects. It turned out that Pluto occupies only 7% of the mass of the remaining cosmic bodies.

Other dwarf planets

Since the first two criteria coincided, it was decided to define Pluto in the category of dwarf planets, and also classify them as plutoids. Now this is a type of dwarf planets that also must meet certain criteria. In particular, spherical bodies with a small mass are considered plutoids. They should revolve around the sun. In this case, the orbit should have a larger radius than the orbit of Neptune. In addition to Pluto, today are considered plutoids: Eris, Makemake and Haumea.

Interesting fact: on Pluto, one day corresponds to six Earth days, and one full rotation around the Sun (by Earth's standards a year) takes as long as 248 years.

Officially, Pluto was added to the list of minor planets under the number 134340 (September 7, 2006).It is interesting that if scientists from the very beginning correctly characterized this object, then in the catalog it would have occupied a place in the first thousands. The only difference between an ordinary planet and a dwarf planet now is only in the size of the objects. In other parameters, they coincide.

Immediately after the discovery of Pluto, the union of astronomy carried it to the planets, since before that other bodies in the Kuiper belt had not been studied. But further space research cast doubt on Pluto's status. During the lengthy debate of 2006, he was transferred to a new category of dwarf planets. The decision was made after the results of Pluto’s assessment according to several criteria. Since the mass does not allow it to displace other cosmic bodies beyond the boundaries of the orbit and makes up only 7% of the mass of the remaining objects of the belt, it cannot be a planet.