Question

what is difference between in
( A ) planets and Asteroids,
( B ) planets and dwarf planets.

And how Pluto was got demoted to dwarf planet in 2006 by International Astronomical Union ?​

Answer 1

Question :

• Difference between Planets and Asteroids.

Answer :

Planets :

• Large objects are planets.

• Planets are confirmed to a eclipsed plane.

• They move on a Order.

• Planets can have Rocky, Solid, Icy, gaseous substances etc.

Asteroids :

• Small bodies are Asteroids.

• They move on a free space.

• Mostly they are made up of c-type (chondrites).

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Planets :

• Large objects are planets.

• Planets are confirmed to a eclipsed plane.

• They move on a Order.

• Planets can have Rocky, Solid, Icy, gaseous substances etc.

Dwarf Planets :

• Dwarf planets do not have a particular region for own.

• Its not an Satellite.

• It will stay in a Sun's direct orbit.

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Pluto was considered as a dwarf planet since 2006, Because it does not obey the three conditions which was given by IAU which describes a full planet.

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Answer 2

⭐⭐ Answer ⭐⭐

( A ) Planets

• A planet has a definite atmosphere on its surface.
• A planet is a celestial body orbiting around it's own star. ( home star ) , for example, For The earth its home star is - The Sun.
• It is a stellar remnant that is massive enough to be rounded by it's own gravity , but not enough for nuclear fusion in it's core to supply itself as a source of light.
• Has sufficient mass to assume the hydrostatic equilibrium ( nearly a round shape )
• Has cleared the neighbourhood around its orbit. for example: around 4.5 billion years ago , when our earth was young, a planet similar like mars named as 'Theia' crashed into the earth, but here barely earth survives from the massive collision. And our earth perfectly created its orbit.
• Planet's orbit must be in ecliptic plane covering by an celestial sphere. ( which we get equinox, winter solstice and summer solstice , this theory contributes to planets like Earth, Mars, Venus and Mercury, which means only inner planets of the solar system , but outer planets also have ecliptic plane but not exactly like the inner planets ).
• Planets contains at least moons. ( As mercury and Venus has no moons because it's too close from the sun , As sun has powerful gravitational forces it will captured the moons from these planets. )
• Planets have all differentiative layers which can distinguish each on it.

Asteroids

• Asteroids are minor planets, especially of inner solar system are comprised this in form of belt .Larger Asteroids are called planetoids.
• Asteroids has all properties like planets excepts some of the criteria , they are :

1. They don't have a definite atmosphere.

2. They don't have any ecliptic plane . 3. They don't have an Orbit , because they will affect by gravity of any Astronomical object. They will change orbits if they will find itself a strong object whose gravitational attraction is more than other one.

4. They don't have any moon. But some planetoids can have a small grain shape of object called meteoroids.

5. They don't have cleared any neighbourhood object.

• What asteroid is most likely to hit earth: with a mean diameter of approximately 7kms . Apollo asteroid (53319) 1999 JM8 is likely the largest known potentially hazardous object, despite it's fainter absolute magnitude of 15.2 ,The last asteroid that hit to earth was Chixculub asteroid, with a diameter of 13.75 kms.
• Asteroids are not massive like planets , unlike planets , their cores are not formed in early solar system which they don't generates any magnetic field around them.

There is one similarities between planets and Asteroids. That they both made up of planetesimals, which is known as an ancestors of proto-planets. several of rocky particles collided which makes bombardment ,that produced heat energy which caused a contact force of planetesimals, there were all form together to give birth a planets. ( contact force initiates to bring heat energy ).

( B ) As, dwarf planets has all it's characteristic except one : They has not cleared its smaller bodies from it's orbit. As the largest known dwarf planet is Pluto, and it's largest known is Charon , as Pluto is the ninth most planet of the solar system. Charon is called as Pluto 1, because of high-mass ratio, their barycenter is outside of the radius of pluto, and the Pluto-Charon system has been referred to as a double dwarf planet.

For these , Pluto was demoted to status of planet as a "Dwarf Planet" . Each known dwarf planet is smaller than the Earth's moon. Pluto is named for the ' roman god of the underworld ' .