Geography: Members of the solar system

Geography: Members of the solar system

The solar system is made up of the Sun, eight planets, satellites, and other celestial bodies.
1.Sun

• The only star in our solar system and powerhouse of the solar system.
•  Composed of Hydrogen (73%), Helium (25%) gases and other metals. Sun carries almost 99% mass of our solar system.
• Approximately 15 crore Kilometres further away from Earth. It takes around 8 minutes 30 seconds for light at the speed of 3 lakh Km/sec to reach the earth.
• Temperature at surface= 5800 K or 5600 degree Celsius.
• Temperature at the centre= 15.7 million K

2. Mercury

• Closest planet to the Sun and very hot planet.
• Smallest planet in the solar system with a diameter of 4900 Km.
• Fastest Planet with speed of 172500 Km per hour to complete revolution around Sun in 88 days.
• The planet with no water and gases like Nitrogen, Hydrogen, Oxygen and Carbon Dioxide.
• It has no satellite of its own.
• It takes 1408 hours to complete a rotation.

3. Venus

• Hottest planet in the solar system with the surface temperature of 478 degree
  Celsius.
• Also known as “Earth’s Twin”. It is because of the similarity in size and mass
  between Venus and Earth.
• One of the two planets in the solar system which rotate around the axis in a
  Clockwise direction.
• Brightest Star in the Solar system. It can be seen in the morning and evening with
  open eyes. So, known as “Evening Star” and “Morning Star”.
• Venus has no moon or satellite of its own.
• It rotates from east to west while the Earth rotates from west to east.
• It takes 5,832 hours to complete a rotation.

4.Earth

• Also known as “Blue Planet” because of the presence of water on it.
• It has one natural satellite named “Moon”.
• The Earth is the only planet in the solar system on which life is known to exist.
• The axis of rotation of the Earth is 23.5 degrees relative to the orbital plane – the
  plane of Earth’s orbit around the sun. The tilt is responsible for the change of
  seasons on the Earth.
• The Earth has only one moon.
• The Earth takes 24 hours to complete a rotation.

5. Mars

• Known as “Red Planet” because of Iron-rich red soil.
• Second smallest planet in the solar system after Mercury.
• Has two natural moons “Phobos” and “Deimos”.
• Has a thin atmosphere and surface with valleys, craters, deserts, and ice caps etc.
• “Olympus Mons” – Largest volcano and the tallest mountain in the solar system
  lies on Mars.
• Mars has two small natural satellites.
• It takes 25 hours to complete a rotation

6. Jupiter

• Largest planet of the solar system with the shortest rotation
• Has an atmosphere filled with Hydrogen, Helium and other gases
• The third brightest object in the night sky after the Moon and Venus
• Great Red Spot, a giant storm in the solar system exists on this planet.
• Has at least 63 moons, including 4 large Galilean Moons “Io, Europa, Ganymede, and Calisto” which were discovered by Galileo. “Ganymede” is the largest among them.
• It has an unclear ring around it.
• It takes only 10 hours to complete a rotation.

 

7. Saturn

• Second largest planet in the solar system and a gas giant.
• Has bright and concentric rings around it which are made up of tiny rocks and pieces
  of Ice.
• Saturn can float on water because it has less density than water.
• Has at least 62 moons and Titan been the largest among them.
• The Saturn is yellowish in colour.
• It has an icy ring around it.
• It takes 11 hours to complete a rotation (second-shortest day in the solar system).

 

8. Uranus

• Has the third- largest planetary radius and fourth largest planetary mass in the Solar
  system.
• Greenish in colour.
• Discovered by William Herschel in 1781.
• Known as “Ice Giant”. The atmosphere of Uranus is composed of Hydrogen and Helium primarily, but it also contains more water, ammonia etc.
• Has coldest planetary atmosphere in the solar system.
• Rotates clockwise on its axis like Venus but unlike other planets
• Has at least 27 moons. Famous moons- Miranda, Ariel and Umbriel
• Uranus also rotates from east to west (like Venus).
• It has a highly tilted rotational axis.
• It takes 17 hours to complete a rotation.

9. Neptune

• It is also “Ice Giant”. Atmosphere primarily composed of Hydrogen and Helium.
• Bluish in colour because of Methane.
• Fourth largest planet and the third most- massive planet in the solar system
• Discovered by Johann Galle and Urbain Le Verrier in 1846. The only planet in the solar system found by Mathematical Predictions.
• Has known 14 satellites. Famous moon – Triton.
• It is the eighth and most distant planet in our solar system.
• The Neptune is dark, cold and has a presence of supersonic winds.
• It takes 16 hours to complete a rotation.

10. Pluto

• As per the new definition of Planets determined by International Astronomical Union (IAU), Pluto has been omitted from the list of planets in 2006.
• Pluto is considered as a dwarf planet (size between planets and asteroids) now and it is a member of Kuiper Belt.
• Kuiper Belt is a spherical boundary outside the orbit of Neptune containing a number
  of asteroids, rocks, and comets.

11. Planets

• There are eight planets in our solar system.
• In order of their distance from the sun, they are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune

12. Inner Planets

• These planets are very close to the sun.
• They are made up of rocks.
• Inner Planets are: MERCURY, VENUS, EARTH, MARS

 

13. Outer Planets

• Very far from the sun are huge planets made up of gases and liquids
• Outer planets are: JUPITER, SATURN, URANUS, NEPTUNE

 

14. Asteroids

• Asteroids are numerous tiny bodies that also move around the Sun apart from the stars, planets, and satellites.
• They are found between the orbits of Mars and Jupiter.

 

15. Meteoroids

• Meteoroids are small pieces of rocks that move around the sun

16. Constellations

• Different groups of stars form various patterns and they are called constellations. Saptarshi is an example of constellations.
• In ancient times, with the help of stars, directions were determined during night time. The North Star (Pole Star) indicates the north direction and it remains in the same position in the sky.
• Celestial bodies that do not have their own heat and light and lit by the light of the
  stars are called planets