Geography Notes for SSC, Railway Exams

Geography Notes for SSC, Railway Exams

A Good News for all of you. From Today onwards we will provide you the series of SSC Exams Notes from where lots of questions were frequently asked. Today in this Article we will Provide you the details facts and Figures on The Universe and its Solar System. This is the First Part of Geography Notes. Based on Subjects we will cover each and every Topics day by day. Those who are following us can note down these important points. Each and every points which we mentioned is important for SSC CHSL, CGL 2018 or Upcoming Railway Exams. 

The Universe

• According to the Scientists, the outward expansion of the world is the result of a powerful, violent explosion (Big Bang) which occurred about 13.7 billion years ago. 
• The origin of the universe is explained by Big Bang Theory. The theory was formulated and proposed by Georges Lemaitre.
• There are about 100 Billion galaxies (10^11) galaxies in the universe.
• The Milky Way Galaxy is the home of the solar system including earth. Its shape is spiral.
• The Canis Major Dwarf Galaxy is the latest known galaxy (discovered in 2003).

The Solar System

Name of planets	Distance from Sun	Time Taken for One Revolution around Sun	Time Taken for One Revolution on its axis	No. of Satellites
Mercury	58 * 10^6 Km	88 days	58.6 days	None
Venus	108 * 10^6 Km	224.7 days	243 Days	None
Earth	150 * 10^6 Km	365.26 days	23.9 hours	1
Mars	228 * 10^6 Km	687 days	24.6 hours	2
Jupiter	778 * 10^6 Km	11.9 years	9.9 hours	63
Saturn	1427 * 10^6 Km	29.5 years	10 hours	21
Uranus	2870 * 10^6 Km	84 years	16.2 hours	15
Neptune	4504 * 10^6 Km	164.8 years	18.5 hours	8

Important Facts about Solar System

Jupiter	Largest Planet
Mercury	Smallest Planet
Venus	Brightest Planet
Mars	Red Planet
Earth	Blue Planet
Mercury	Nearest planet to Sun
Neptune	Farthest planet to Sun
Venus	Morning Star
Jupiter	Planet with Red Spot
Venus	Evening Star
Venus	Hottest Planet
Venus	Nearest Planet to Earth
Neptune	Coldest Planet
Venus	Slowest Rotation in Solar System
Mercury	Fastest Rotation in Solar System
Neptune	Slowest revolution in Solar System
Sirius (Dog Star)	Brightest Planet outside solar system
Jupiter	Fastest Rotation in Solar System
Smallest Satellite	Deirmos
Largest Satellite	Gamymede
Proxima Centuari	Closest Star  of Solar System

Important Facts about Sun

Total Life	10 Billion Years
Age	4.6 Billion Years
Time taken by the Sunlight to reach earth	8 min and 16.6 sec
Chemical composition	Hydrogen (71%), Helium (26.5 %) and other gases (2.5%)
Speed of light (in vacuum)	300000 Km
Rotation Speed	33 days (with respect to  Poles) 25.63 days (with respect to equator)
Diameter	1391980 Km
Temperature of the core	15000000 Degree K
Average Distance from earth	149598900 Km

Important Facts about Moon

Diameter	3476 Km
Mass	The mass of Earth * 0.0123
Average Distance from Earth	384365 Km
Surface Temperature	-233 to 123 Degree Celsius
Time taken by the moon light to reach the earth	1.3 Secs
Percentage of surface visible from earth	59%
Ratio of Diameter of moon to that of earth	1: 3.7
Revolution Speed	27days 7 hrs 43 min and 11.47 Sec
Rotation Speed	27days 7 hrs 43 min and 11.47 Sec

Important Facts about Earth

Age	4550 Million Years
Mass	5.976 * 10 ^ 24 Kg
Volume	1.083 * 10^24 L
Mean Density	5.518 Kg/L
Total Surface Area	510 Million Square Km
Total Land Area	29.2% of the total surface area
Total water area	70.8% of the total surface area
Average Density	5.52 (Corresponding to the density of water)
Polar Diameter	12714 Km
Equatorial Diameter	12756 Km
Equatorial Radius	6377 Km
Polar Radius	6371 Km (IUGG)
Equatorial Circumference	40076 Km
Polar Circumference	40024 Km
Mean Surface Temperature	14 Degree Celsius
Escape Velocity	11.2 Km/ Sec
Highest Land Point	Mount Everest (8848 m)
Lowest Land Point	Dead Sea (396 m)
Greatest Ocean Depth	Mariana Trench (11033 m)
Rotation Speed	23Hrs 56 Min and 40.91 Sec
Revolution Speed	365 days 5hrs and 45.51 Sec
Aphelion (Maximum Distance from Sun)	About 152 Million Km
Perihelion (Minimum Distance from Sun)	About 147 Million Km
Dates on which the day and night are equal	23rd September (Autumnal Equinox) and 21st March (Vernal Equinox)
Dates of longest days and shortest nights	22nd December (Winter Solstice) and 21st June (Summer Solstice)
Composition of Earth	Consists of 100 elements, Major 8 elements – Oxygen (46.5%), Silicon (27.72%), Aluminium (8.13%), Iron (5.01%), Calcium (3.63%), Sodium (2.85%), Potassium (2.62%) and Magnesium (2.09%)

Structure of Earth

The Crust –

• The outermost solid cover (shell) of the earth is known as the Earth’s Crust.
• The crust varies greatly in thickness and its composition is as small as 5 Km. In some mountain ranges, it extends up to 70 Km in depth.
• The crust of earth is made of 2 layers i.e. Sial and Sigma.

Mantle –

• It lies below the crust.
• The thickness of mantle is about 2900 Km.
• The line of separation between the mantle and crust is called as Mohoviricic Discontinuity.

Core –

• The core of earth lies beyond a depth of 2900 Km.
• The outer core is in molten form and is 2100 Km thick while the inner core is in plastic form and is 1370 Km thick.
• It is made up of iron and nickel and is responsible for Earth’s magnetism.
• The temperature in the Earth’s core lies from 2200 Degree Celsius to 2750 Degree Celsius.
• The Line of separation between the mantle and the core is known as Gutenberg-Wiechert Discontinuity.