Theory:

Inner or Terrestrial Planets:
Mercury
Venus
Smallest and closest planet to the SunSecond planet from the Sun
Airless and waterlessplanet.Earth’s Twin (almost the same size as the Earth)
No atmosphereNo atmosphere
Experiences extremes of temperatureLongest rotation period (\(243\) days)
No satellitesNo satellites
Mercury can be viewed in the morning and evening with naked eye.Visible in the mornings and the evenings. Also called as the Morning Star and the Evening Star.
Rotates from West to East.It rotates in the opposite direction to all other planets except Uranus, i.e. East to West.
 After the Moon, it is the brightest natural object in the night sky.
Named after the Roman deity ‘Mercury’, the Messenger to the Gods.Named after the Roman Goddess of love and beauty.
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  • Mercury is only about as wide as the Atlantic Ocean.
  • Venus has yellowish clouds made of sulphur and sulphuric acid cover the entire planet causing light to reflect off the surface.
Inner or Terrestrial Planets:
Earth
Mars
Third Planet from Sun and fifth largest planet.Fourth planet from the Sun and second smallest planet in the solar system.
Only planet known to support life. It also has polar ice.
Atmosphere mainly made of: Nitrogen (\(78\)%) and Oxygen (\(21\)%)Thin atmosphere
Rotation period: \(23\)hours, \(56\)minutes
 
Satellite: MoonSatellites: Phobos and Deimos
Also known as Blue planet’ or ‘Watery planet’ because three-fourth of the Earth is covered by water.Appears red, due to the presence ofiron oxide on its surface
Often described as The Red Planet.
Rotates from West to East
Rotates from West to East
The only planet in the solar system which is not named after any Greek or Roman deity.Named after the Roman God of war.
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Other important facts about Earth
Polar diameter: \(12,714\)  km
Equatorial diameter: \(12,756\)  km
The Earth revolves around the Sun at a speed of about \(30\)  kmper second.
Important!
The distance between the Sun and the Earth is about \(150\) million kilometres (or \(1\)\(Astronomical\)\(Unit\)).  
Note: The below image is from the textbook - to be restructured
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Planets in Order of Size
Jupiter (Largest)> Saturn > Uranus > Neptune > Earth > Venus > Mars > Mercury (Smallest)