Definition of a planet | Wikipedia audio article
Channel: wikipedia tts
Date: 2019-06-02

This is an audio version of the Wikipedia Article:
https://en.wikipedia.org/wiki/Definition_of_planet


00:02:39 1 History
00:02:48 1.1 Planets in antiquity
00:07:34 1.2 Planets in the Middle Ages
00:09:10 1.3 Earth
00:10:59 1.4 Modern planets
00:13:39 1.5 Satellites
00:16:00 1.6 Minor planets
00:19:39 1.7 Pluto
00:23:34 2 IAU definition
00:27:02 3 Acceptance of the IAU definition
00:27:47 4 Ongoing controversies
00:30:40 4.1 Clearing the neighbourhood
00:31:35 4.2 Hydrostatic equilibrium
00:35:06 4.3 Double planets and moons
00:37:45 4.4 Extrasolar planets and brown dwarfs
00:41:22 4.4.1 Planetary-mass stellar objects
00:48:47 4.5 Semantics
00:51:07 5 See also
00:53:33 6 Notes



Listening is a more natural way of learning, when compared to reading. Written language only began at around 3200 BC, but spoken language has existed long ago.

Learning by listening is a great way to:
- increases imagination and understanding
- improves your listening skills
- improves your own spoken accent
- learn while on the move
- reduce eye strain

Now learn the vast amount of general knowledge available on Wikipedia through audio (audio article). You could even learn subconsciously by playing the audio while you are sleeping! If you are planning to listen a lot, you could try using a bone conduction headphone, or a standard speaker instead of an earphone.

Listen on Google Assistant through Extra Audio:
https://assistant.google.com/services/invoke/uid/0000001a130b3f91
Other Wikipedia audio articles at:
https://www.youtube.com/results?search_query=wikipedia+tts
Upload your own Wikipedia articles through:
https://github.com/nodef/wikipedia-tts
Speaking Rate: 0.7955475807260138
Voice name: en-US-Wavenet-E


"I cannot teach anybody anything, I can only make them think."
- Socrates


SUMMARY
=======
The definition of planet, since the word was coined by the ancient Greeks, has included within its scope a wide range of celestial bodies. Greek astronomers employed the term asteres planetai (ἀστέρες πλανῆται), "wandering stars", for star-like objects which apparently moved over the sky. Over the millennia, the term has included a variety of different objects, from the Sun and the Moon to satellites and asteroids.
By the end of the 19th century the word planet, though it had yet to be defined, had become a working term applied only to a small set of objects in the Solar System. After 1992, however, astronomers began to discover many additional objects beyond the orbit of Neptune, as well as hundreds of objects orbiting other stars. These discoveries not only increased the number of potential planets, but also expanded their variety and peculiarity. Some were nearly large enough to be stars, while others were smaller than Earth's moon. These discoveries challenged long-perceived notions of what a planet could be.
The issue of a clear definition for planet came to a head in January 2005 with the discovery of the trans-Neptunian object Eris, a body more massive than the smallest then-accepted planet, Pluto. In its August 2006 response, the International Astronomical Union (IAU), recognised by astronomers as the world body responsible for resolving issues of nomenclature, released its decision on the matter during a meeting in Prague. This definition, which applies only to the Solar System, states that a planet is a body that orbits the Sun, is massive enough for its own gravity to make it round, and has "cleared its neighbourhood" of smaller objects around its orbit. Under this new definition, Pluto and the other trans-Neptunian objects do not qualify as planets. The IAU's decision has not resolved all controversies, and while many scientists have accepted the definition, some in the astronomical community have rejected it outright. In particular, some favor a strictly geophysical definition of a planet.