How many people are on this planet - Computers & Internet

Any professional astronomer or astro club.

Nibiru is a mythical planet, sometimes called planet X, based on the old idea that irregularities in the orbits of the outer known planets could only be explained by the existence of a further, large, undiscovered planet.

However this idea, which started in the 19th Century, lost credence when it was found that the supposed irregularities were simply due to miscalculation of the real mass of Neptune.

Then when small objects began to be discovered in the Kuiper Belt beyond Neptune, the idea of Planet X reappeared. One of these objects was Eris, a bit smaller than Pluto, and too small to be a Planet X.

Modern telescopes and techniques have now all but ruled out the idea that Planet X exists.

Edit:Update: Using the latest sensitive observations NASA has discussed the possible existence of a "super-earth" very very far out in an extreme orbit. They have not found it, but say that the orbits of objects beyond the Kuiper Belt seem to suggest its existence.

http://www.news.com.au/technology/science/space/nasa-admits-the-mysterious-planet-nine-is-real-but-says-deadly-nibiru-is-a-f raud/news-story/5037076a579e7e5c642396d307b6aeee

However the idea of a Planet X, or Nibiru, crashing into Earth, has again been dismissed.

according to current discovery (Neptune, Pluto & Uranus) are not planet but let me know according to indian astrology there are 9 planet but the planet which has been discovered as non planet by nasa is there anything writen anywhere that astrologers are talking about the planet among 9 planet is that the same planet which the nasa is talking about and also would like to make you aware that space craft known as puspak viman has been discovered where in india more that 5000 b.c that simply mean that we indian are more advance as per current technologies so definitely our ancient scientist who were called (Rissi) were aware of this discovery before and even though if they have describe about 9 planet that means 9 planet do exist and our current scientist and nasa had not yeat discovered it.

It's behind you

Bernard, check the links.
Planets beyond Neptune

Hypothetical Planet Overview Planets NASA Solar System Exploration

planet Google Search

The 5 planets visible to the eye have been known for all human history, and have therefore had many names in different cultures. Eventually except for Earth, the names of the planets came to be from Roman and Greek mythology, like much else we have inherited.

Then when Uranus was discovered this tradition was already established, although its discoverer Herschel wanted to call it planet George, after the King. What a cringe.

When Pluto was discovered there was a sort of unofficial poll or contest, with the result we know, because Pluto is the god of the underworld, cold and dark.

http://rome.mrdonn.org/romangods/planets.html

The way things are going this planet will survive until the sun goes nova or burns out. Whether humans survive that long or go the way of the dinosaurs is a different matter.

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.

That's only eight. Pluto, which used to be the ninth planet, was demoted from "planet" to "dwarf planet" a few years ago.

The biggest planet in our solar system is Jupiter. Jupiter is the fifth planet from the sun and the largest in the solar system.

Astronomers say they have discovered what appears to be an entirely new kind of planet, an extra-large gas giant unlike any known world in our solar system or beyond. The planet, dubbed HAT-P-1, is located some 450 light-years from Earth in the constellation Lacerta.
It is the largest planet ever discovered and boasts a radius nearly 1.4 times larger than Jupiter's.
HAT-P-1 is also the least dense of all known planets.

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