What are the characteristics of 8 planets?

Answer 1

In our solar system, there are 8 major planets and 5 dwarf planets, for a total of 13 planets.

Including dwarf planets, there are also minor planets. As of 2017, the orbits of 734,274 minor planets were archived at the Minor Planet Center, 496,815 of which had received permanent numbers.

There are however many more exoplanets or planets outside the solar system - almost 2,000 have been identified to date, and statistically speaking there may be as many as 200 billion planets in our galaxy.

As to why there are the current number in our own system - this can be attributed to configuration of matter in the proto-nebula of gas and dust from which the planets (and Sun) formed, where conditions happened to be favorable to the formation of the planets as they collected mass through gravitational effects.

Note that leading theory indicates the solar system layout may have been very different - for example, a spectacular collision may have stripped Mercury of a significant amount of its mass; Venus may have rotated differently; Uranus and Neptune possibly occupied orbits much closer to the Sun.

Some planets may have been flung into space out of our solar system; it's even possible at one or more times that the Sun temporarily captured a rogue planet formed outside the solar system.

So, the short answer for why the current count of planets is that, the current configuration happens to be fairly stable.

Answer 2

Mercury: very thin almost no atmosphere, a lot of craters due to the thin atmosphere, 0.387 astronomical units away

Venus: very thick atmosphere, hottest planet, has an intense greenhouse effect, sulfur rain and lakes are on the surface

earth: only planet known with life, only planet known with liquid water oceans, only planet known with advanced technology

mars: very thin atmosphere again, dust storms on the surface, the only planet with working craft on them Venus had one for about 12 minutes before it melted due to the heat, all other planets were gassy and the pressures crushed them

Jupiter: largest planet [terrestrial and Jovian], cloud bands that move with the planet, voyager 1 and 2 visited this planet first

Saturn: not the only planet with rings but has the most noticeable, has a moon that formed between a ring Cassini probe ventured here

Uranus: it has rings as well, has an elliptical orbit, only planet who's axis is 90 degrees

Neptune: also has a storm like Jupiter's big red spot, the atmosphere is mostly composed of hydrogen, helium, methane, and ammonia causing the planet to be blue, has faint rings

Answer 3

Actually, they are the 8 major planets in the solar system. They are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Please note that there are many more minor planets in our solar system, and possibly billions of other planets in the universe. ^-^

Answer 4

Beyond the boundaries of our own solar system, there are countless additional planets. The Kepler Space Telescope has discovered over 500 so far, and the theory & design of the Kepler Telescope indicates that we are unlikely to observe the majority of them, because they do not occult the star. So discovering as many planets as we have indicates that planets must be as common as, well, "dirt".

Answer 5

There are eight planets and several 'dwarfs' in our own solar system.

Outside of our solar system, evidence of over 700 planets has been found

(as of mid 2013), and the conjecture is building that there may be planets

orbiting MOST stars.

Answer 6

We know from observing the sky with a telescope.

As of 2017, it depends on whether you count major planets only, or all planets.

The 8 major known planets in order from the Sun are:

1. Mercury
   
2. Venus
   
3. Earth
   
4. Mars
   
5. Jupiter
   
6. Saturn
   
7. Uranus
   
8. Neptune
   

If you list ALL 13 known planets in order, including dwarf planets, they are:

1. Mercury
   
2. Venus
   
3. Earth
   
4. Mars
   
5. Ceres
   
6. Jupiter
   
7. Saturn
   
8. Uranus
   
9. Neptune
   
10. Pluto
    
11. Haumea
    
12. Makemake
    
13. Eris
    

Dwarf planets also fall under the category of minor planets, of which there are thousands in our solar system. As of 2017, the orbits of 734,274 minor planets were archived at the Minor Planet Center, 496,815 of which had received permanent numbers. The largest minor planet that is not considered to be a dwarf planet is Sedna.

Answer 7

Because gravity in a solar system seeks equality. Should there have been a ninth planet it would have been exercised to the next solar system.

Answer 8

Definitely. Eight of them are in our solar system, and hundreds more have been identified in orbits around other stars.

Answer 9

Definitely. Eight of them are in our solar system, and hundreds more

have been identified in orbits around other stars.