Components of the Solar System, Planets and Their Major Moons

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Our solar system consists of the sun, eight planets, dwarf planets (Pluto, Ceres, Eris), satellites & countless minor planets, asteroids, meteors, comets, etc.

Nicolaus Copernicus was the first to develop a mathematically predictive heliocentric solar system — an astronomical model in which the Earth and planets revolve around the Sun.
Most large objects in orbit around the Sun lie near the plane of Earth’s orbit, known as the ecliptic. The planets are very close to the ecliptic, whereas comets and Kuiper belt objects (like Pluto) are frequently at greater angles to it.
The orbits of the planets around the sun are nearly circular, but many comets, asteroids, and Kuiper belt objects follow highly elliptical orbits.

The idea of a spherical Earth was floated by Pythagoras around 500 BC & later validated by Aristotle in 340 BC.
Ptolemy placed the Earth at the centre of his geocentric model of the solar system. Nicolaus Copernicus refuted the geocentric model with his heliocentric model.
Strabo is best known for his work Geographica (“Geography”), which presented a descriptive history of people and places from different regions of the world know during his lifetime.

Kepler’s Laws of Planetary Motion

The orbit of a planet is an ellipse with the Sun at one of the two foci.
A line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time.
The square of the orbital period of a planet is proportional to the cube of the semi-major axis of its orbit.

Planet	Surface Temp in ֯C	Period of Rotation	Period of Revolution	Distance in AU	Diameter (km)		Size Rank	Moons	Density (gm/cm³)	Specific gravity (m/s²)
1. Mercury	+427	58 days	87 days	0.4	4,878	0.38	8	0	5.4	3.7	0.38
2. Venus	+480	243 days	224 days	0.7	12,104	0.95	6	0	5.2	8.9	0.9
3. Earth	+22	23:56 hrs	365 days	1	12,756	1.00	5	1	5.5	9.8	1
4. Mars	-23	1.025 days	687 days	1.5	6,787	0.53	7	2	3.9	3.7	0.38
5. Jupiter	-150	9.9 hrs	11.9 years	5.2	1,40,000	11.19	1	79	1.3	24.9	2.53
6. Saturn	-180	10.7 hrs	29 years	9.6	1,16,000	9.46	2	82	0.7	10.4	1.06
7. Uranus	-214	17 hrs	84 years	19.2	51,000	4.11	3	27	1.3	8.8	0.9
8. Neptune	-220	16 hrs	164 years	30.0	48,000	3.88	4	14	1.6	11.1	1.13
Pluto (dwarf)	-223	6.39 days	248 years	39.5	2,377	0.18	9	5	1.9	0.6	0.06
Some of the values given in the table are rounded off.