What is the Solar System?

 

The Solar System is the Sun and everything gravitationally bound to it — eight planets, dwarf planets, moons, asteroids, comets, and distant icy reservoirs — formed about 4.568 billion years ago and located in the Milky Way’s Orion–Cygnus arm. (If you’re in Dhaka today, these objects are the same; their visibility from Earth depends on date and time.) NASA Solar System Exploration Wikipedia

What the Solar System is

• Definition: The Solar System is our star (the Sun) plus all objects bound to it by gravity: the eight planets, dwarf planets (e.g., Pluto, Ceres), moons, millions of asteroids and meteoroids, and countless comets. 
• Age: About 4.568 billion years old. 
• Location: Situated in the Orion–Cygnus (Local) arm of the Milky Way galaxy. Wikipedia

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Main components (short, bold facts)

• The Sun: A G2V main‑sequence star that contains >99% of the Solar System’s mass.
• Planets: Eight major planets in order from the Sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune. 
• Dwarf planets: Examples include Pluto and Ceres; smaller bodies that orbit the Sun but do not clear their orbital zones.  
• Asteroid Belt: Rocky debris between Mars and Jupiter. 
• Kuiper Belt and Oort Cloud: Kuiper Belt is a disk of icy bodies beyond Neptune (includes Pluto); the Oort Cloud is a distant spherical reservoir of comets. 

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Quick comparison table of the eight planets

Planet	Type	Mean distance (AU)	Diameter (km)	Notable feature
Mercury	Rocky	0.39 AU	4,880 km	Closest to Sun; extreme temperatures
Venus	Rocky	0.72 AU	12,104 km	Thick CO₂ atmosphere; runaway greenhouse
Earth	Rocky	1.00 AU	12,742 km	Only known life; liquid water
Mars	Rocky	1.52 AU	6,779 km	Red color; largest volcanoes
Jupiter	Gas giant	5.20 AU	139,820 km	Largest planet; Great Red Spot
Saturn	Gas giant	9.58 AU	116,460 km	Prominent ring system
Uranus	Ice giant	19.2 AU	50,724 km	Tilted axis; methane-rich atmosphere
Neptune	Ice giant	30.1 AU	49,244 km	Strong winds; distant blue world

(Distances and diameters are rounded averages; planet ordering and types are standard astronomical classifications.) Britannica Wikipedia

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Why this matters (practical context for Dhaka)

• Space science and satellites: Understanding the Solar System underpins satellite orbits, space missions, and astronomy outreach programs available in Bangladesh. 
• Observation tip: From Dhaka, bright planets (Mercury, Venus, Mars, Jupiter, Saturn) are visible at different times of year; check a local sky chart or planetarium schedule for tonight’s visibility.