Solar System PDF

## SOLAR SYSTEM ### Solar System - Venus - Mercury - Neptune - Saturn - Uranus - Mars - Earth - Jupiter ### Milky Way Galaxy - Nearest galaxy: Andromeda Galaxy - Study of Universe: Cosmology - Universe - Milky Way Galaxy - Solar System - 8 planets ### Origin of Universe - Theories given: -...

## SOLAR SYSTEM ### Solar System - Venus - Mercury - Neptune - Saturn - Uranus - Mars - Earth - Jupiter ### Milky Way Galaxy - Nearest galaxy: Andromeda Galaxy - Study of Universe: Cosmology - Universe - Milky Way Galaxy - Solar System - 8 planets ### Origin of Universe - Theories given: - Big Bang Theory ### Accelerated Expansion of the Universe - Infinitely hot and dense single point - Exploded - 13.7 billion years - Dark age - Dark energy accelerated expansion - Big Bang Inflation - Relic radiation (CMB) ### Formation of our Solar System - Nebular Theory, 1755: by Immanuel Kant - 1796: modified by Laplace - Nebula: A giant cloud of dust and gas - Nebular Hypothesis - Cloud - Molecular gas - Dust - Self-gravity contracts a gas cloud - Conservation of angular momentum pulls cloud into a disk - Disk begins to rotate - Central mass forms (proto-Sun) - Centrifugal force balances gravitational forces and a ring forms - Ring forms into a planet - H + H - →Formation of Sun (mostly made of ​H​2 and He) - (Nuclear Fusion) - ↓ - ​H​2 70% - Indian Institute of Astrophysics HQ: Bangalore ### Celestial Bodies - Two types: - Luminous: Self-glowing, eg: stars - Non-Luminous: Not self-glowing, but can reflect light from other sources. Eg: Moon, Asteroids, Meteor, Comets, Meteorites - 1. Asteroids: they are small, rocky objects that orbit the Sun - 2. Meteoroids/Meteors: enters Earth's atmosphere and burn up in Mesosphere (shooting stars) - 3. Comet: Small icy dirt balls that orbit the Sun, burn upon reaching Sun - 4. Stars - Stars - luminous bodies - Colour: Depends on temperature - Group of stars: Constellation - Largest: Hydra - Urja Major: Sapta Rishi - Brightest star in Orion Constellation: Rigel - Brightest star in night sky (Coverall): Sirius (Dog Star) - Closest star to Earth: Sun - Distance from Earth: 150 million km (1.5 x 10^6 km) - After Sun, it is Proxima Centuri - Light Year/Parsec: celestial distances - 1 LY: 9.46 x 10^12 km - 1 Parsec: 3.26 LY - India's first Solar Mission - ADITYA L1 mission ISRO, India - Sun - The only star in our solar system and powerhouse of solar system - Composed of Hydrogen (73%), Helium (25%) and other metals - Carries 99% mass of our solar system - Approx 109 times of Earth - Takes 8 minutes 30 seconds for light at speed of 3 lakh km/sec to reach Earth - Temperature at surface = 5800 K/ 5600 C - Temperature at centre = 15.7 million K - Outer layer: CORONA ### Sun's Structure - Inner zone - Radiative Zone - Convection Zone - Subsurface Flows - Photosphere - Chromosphere - Corona ### Asterism - Constellation - Astorism, pattern of stars - Big Dipper - Ursa Major - Great Bear - Saptarshi - Cassiopical, W shape ### Asterism pattern formed - Cygnus - Cross-shaped - Deneb - Albireo ### January Evenings - Betelgeuse - Bellatrix - Orion - Shedar - Hourglass - "Orion's Belt" - Orion Nebula (M42) - Saiph - Rigel - Brightest star ### The Hunter - Sirius - Rigel - Orion - Betelgeuse ### Moon - Earth's natural satellite - Non-Luminous - Radii: 1.74 x 10^6 m - Time of Moon's light, takes to reach Earth: 1.26 secs - Distance b/w Earth and Moon: 3,84,000 km - Gravity = Earth's gravity - 6 - Rotation = Revolution (same) - 60% of it - 27.3 days → Only one side of the Moon is visible (Near side) - Rotation = Revolution → 27 days - Rotation: object's spinning motion about its axis - Revolution: object's orbital motion around another object - All planets rotates from West to East (anti-clockwise) except Venus and Uranus (clockwise) - Chandrayaan 3 - Lander: Vikram - Rover: Pragyaan - Point: Shiv Shakti Point ### 8 Planets - Mercury - Venus - Earth - Mars - Jupiter - Saturn - Uranus - Neptune ### Two Categories - Terrestrial - Jovian ### Kuiper Belt - Terrestrial planets/Interior planets - Jovian Planets/Exterior Planets - Asteroid Belt: b/w Mars and Jupiter - Pandit Jasraj becomes the first Indian musician to have a minor planet named after him: Panditjasraj (300128) - Derived from his date of birth, 28 Jan 1930 ### Characteristics of terrestrial planets - Mercury - Venus - Earth - Mars - Made of rocky material - Very few moons - Surfaces are solid - Relatively small - Don't have rings - Revolves around planets ### Jovian Planets - Jupiter - Saturn - Uranus - Neptune - Halley's Comet: Appears every 76 years - First observed: 1986 - Next in 2061 ### Jovian Planets - Gas Giants - Predominantly Helium and Hydrogen - Jupiter - Saturn - Ice Giants - Contain rock, ice, and mixture of water methane, and ammonia - Uranus - Neptune ### 1st Planet: Mercury - Closest planet to Sun - Smallest planet in solar system - Diameter: 4900 km - Fastest planet, takes 88 days to complete revolution around Sun - Planet with no satellite - Planet with no water and gases like Nitrogen, Hydrogen, Oxygen, and Carbon Dioxide - Fastest revolution: 88 days ### 2nd Planet: Venus - Hottest planet in solar system: traps the gas easily, has thick clouds of H2SO4, and CO2 - Brightest planet in Solar System, also known as "Evening Star" and "Morning Star" - No satellite/Moon - Also known as "Earth's Twin" due to similar mass and size - Venus is also known as Lucifer (light bearer) - Rotates clockwise - Slowest rotation: 243 days ### 3rd Planet: Earth - Closest planet to Earth: Venus and Mercury - The only planet to give support to life - Also known as "Blue Planet": 70% water - It has one satellite: Moon - Densest in the entire solar system ### 4th Planet: Mars - Known as "Red Planet": rich in Iron oxide (red soil) - Second smallest planet in solar system - Two natural moons: Phobos and Deimos - Largest Volcano and tallest mountain of Mars: Olympus Mons ### 5th Planet: Jupiter - Largest planet with shortest rotation- 10 hours (9 hrs 56 mins) - Atmosphere filled with: Hydrogen, Helium, other gases - Third brightest after Moon and Venus - At present total moons: 95 moons at present - Largest satellites: lo, Europa, Ganymede (largest among all), Callisto Call discovered by Galileo) - Has unclear ring around it - It is known as "Winter planet" ### 6th Planet: Saturn - Second largest planet - Has bright and concentric rings made of tiny rocks, gas, dust, ice - It is the least dense planet - Has 146 moons at present (the maximum) - Largest satellite: Titan - 1655: Huygenes (discover Saturn's rings) - 1675: Cassini (discovered gap b/w rings) - Cassini divisions - Titan and Enceladus (satellites of Saturn) show possibilities of life on Saturn ### 7th Planet: Uranus - It is greenish in colour: "Green Planet" due to presence of Methane (CH4) - Discovered by William Herschel in 1781 - Known as "Ice Giant" - Atmosphere has: Hydrogen, Helium, Water, Ammonia, Methane - Rotates clockwise like Venus - Due to its tilt - Coldest planet - Its is tilted to 98° at its axis- Rolling/Lopsided Planet ### 8th Planet: Neptune - Farthest planet - Longest/Slowest revolution →165 days - It is also "Ice Giant" - Atmosphere composed of: Hydrogen, Helium - Neptune - 1 day = 16 hours - Bluish in colour due to Methane - Fourth largest planet and third most massive planet - Discovered by: Johann Galle and Urbain Le Verrier in 1846 (Conly planet found by Mathematical Predictions) - Has 14 satellites, famous moon: Triton - It is the windiest planet ### Pluto - No more a planet in 2006 by International Astronomical Union (IAU) - It is known as dwarf planet and 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 - Pluto's largest satellite: Charon - 1 revolution = 248 Earth years ### Increasing to Decreasing Order - Jupiter - Saturn - Uranus - Neptune - Earth - Venus - Mars - Mercury ### Largest dwarf planets - Pluto - Eris - 2007 OR10 - Haumea - Makemake - Three characteristics of dwarf planets are: - To be in orbit around the sun - Have a nearly spherical shape - Should not be able to clear their orbit of debris - Supernova: Explosion of star - Pulsar: A neutron star - Black hole: A place in space with immense gravity - Pluto: Largest and brightest dwarf planet - Eris: Second largest dwarf planet - Makemake: Third largest and it orbits in 310 yrs - Ceres: Dwarf planet present in asteroid belt - Haumea: Fastest rotating in Kuiper belt