Geography 1 Flashcards
Who is called the “father of geography”?
Eratosthenes
Who was the first to measure the circumference of Earth?
Eratosthenes
- also calculated tilt of Earth’s axis
Who created the first map of the world?
Anaximander
Who made the first map of India?
Ainville
Who first presented India on the world map?
Ptolemy
What is the study of soils in their natural environment called?
Pedology
What is the study of the organisms and their relationship with their environment?
Biogeography
Which is the galaxy closest to us?
Andromeda
Who first proposed that the Sun was the centre of the universe?
Copernicus
Who first proposed that the Sun was the centre of the solar system (not universe)?
Kepler
Who first demonstrated the existence of galaxies beyond the Milky Way?
Edwin Hubble
What are the two missions launched by NASA to study the radiation in the universe?
Cosmic Background Explorer (COBE)
Wilkinson Microwave Anisotropy Probe (WMAP)
What are the two missions launched by NASA to study the origins of the solar wind and how it affects Earth?
Polarimeter to Unify the Corona and Heliosphere (PUNCH) mission
Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites (TRACERS)
What is a star that is bigger than the Sun but not more than twice as big?
Neutron star / Pulsar
Which is the brightest star outside our solar system?
Sirius (Dog Star)
Which star is closest to our solar system?
Proxima Centauri [4.2 light years away]
- then Alpha Centauri [4.3 light years away]
- then Bernard’s Star [5.9 light years away]
What is the Chandrashekhar limit?
1.44 times the mass of the sun
- after which the star will either explode (pulsar) or collapse (black hole)
- predicted by Dr. Chandrashekhar
What is an astronomical unit?
Average distance between Sun and Earth
[60,000 AUs = 1 light year]
What is a parsec?
Distance from the earth to a star that has a parallax of 1 arc second
Size of solar system
10^5 AUs
The electrically charged gases in the Solar System is called _____.
Plasma
What are small solar system bodies?
Components of solar system other than planets, dwarf plants and their satellites
Which is the most widely accepted theory of planetary formation?
Nebular Hypothesis
- by Laplace
- Maintains that 4.6 billion years ago, the Solar System formed from the gravitational collapse of a giant molecular cloud which was light years across.
- Several stars, including the Sun, formed within the collapsing cloud
What causes the energy provided by the Sun?
Nuclear Fusion
- conversion of H to He
What is the surface of the Sun visible to us called?
Photosphere
What is above the photosphere?
Chromosphere
What is the galactic/cosmic year?
The time required for the Sun to orbit once around the center of the Milky Way Galaxy
- 224 million years
What are the dark features in the optical spectrum of the Sun called?
Fraunhofer lines
Which layer of the sun is observable during an eclipse?
Corona
How much time does it take for the Sun’s light to reach Earth?
8 min 16 sec
These hot ionised gases pose a threat to satellite communication.
Solar flares
What are the streams of photons emitted by the Sun as spiral streams called?
Solar winds
What are the solar winds that get trapped by the Earth’s magnetic field called?
Aurora
- Aurora Borealis [North Hem]
- Aurora Australis [South Hem]
What are the bright spots on the Sun called?
Plages
Which spots on the sun affect global climate?
Sunspots
What is another name for gaseous planets?
Jovian
Biggest satellite in the solar system
Ganymede
Green planet in the solar system
Uranus
Brightest planet in the solar system
Venus
Densest plant
Earth
Hottest planet
Venus
Fastest rotation planet
Jupiter
Slowest rotating planet
Venus
Smallest satellite
Phobos
- belongs to Mars
Morning and Evening star
Venus
Only satellite with an atmosphere like Earth
Titan
Which planet has the most satellites in our solar system?
Jupiter [67 moons]
- then Saturn [62 moons]
What are the 4 largest moons on Jupiter called?
Galilean moons
- Io, Europa, Ganymede, and Callisto
Which planet has the Great Black Spot?
Neptune
- almost the size of Earth
The study of the moon is called _____.
Selenology
The moon is also called a _____ planet.
Fossil planet
What elements are majorly found on the Moon?
Silicon, magnesium, iron
What is the Oort cloud?
Source of origin of most comets
- Long-period comets (take > 200 years to complete an orbit around the Sun) come from Oort Cloud.
- Short-period comets (take < 200 years to complete an orbit around the Sun) come from the Kuiper Belt.
What are the three eras that Earth’s geological history is divided into?
Palaeozoic, Mesozoic, Cenozoic
Most element found on Earth
Iron [35%]
How old is the Earth?
4.54 billion years
The Earth rotates in which direction?
West to East
The point in the orbit of the moon or a satellite at which it is furthest from the Earth is called _____.
Apogee
The point in the orbit of the moon or a satellite at which it is nearest to the Earth is called ______.
Perigee
The point in the orbit of a planet is nearest to the sun is called ______.
Perihelion
The point in the orbit of a planet is farthest from the sun is called ______.
Aphelion
Degree of Earth’s incline
66.5
When are the two equinoxes?
21 March [vernal] & 23 Sept [autumnal]
When the Sun is right above the Tropic of Cancer it is called _______.
Summer solstice
When the Sun is right above the Tropic of Capricorn it is called _______.
Winter solstice
Longest day in Northern Hemisphere
21st June
- also the shortest day in Southern Hemisphere
Shortest day in Northern Hemisphere
22nd December
- also the longest day in the Southern Hemisphere
Equal day and night in both hemispheres
21st March & 23rd Sept
How did they decide the Prime Meridian?
The line that passes through the Royal Astronomical Observatory in Greenwich [in 1884]
What is opposite to the Prime Meridian?
International Date Line
How many longitudinal zones is earth divided into?
24
- each 1 hour apart
Which country has the most amount of time zones?
Russia [11]
Where is the Earth in a lunar eclipse?
Between moon and Sun
- on a full moon day
What is the sequence in a solar eclipse?
Sun-moon-Earth
- shadow of moon falls on earth
- on a new moon day
______ is the thinnest layer on Earth with the least density.
Crust
____ and ____ together form the Earth’s crust.
Sial [Si and Al] & Sima [Si and Ma]
- silicon, aluminium and magnesium make up the rocks
Which layer consists of minerals in a semi-solid state?
Mantle
The upper part of the mantle is called ______.
Asthenosphere
The transitional separating the mantle from the core is called ______.
Gutenberg Discontinuity
- Earth’s density and velocity of ‘P’ waves increases
The inner core is in solid/liquid/semi-solid state.
Solid
- or crystalline
The outer part of the core is in solid/liquid/semi-solid state.
Liquid
The core is also known as ____.
Nife [Ni+Fe]
- nickel and iron abundance
Where is the Lehmann discontinuity?
Between Earth’s inner and outer core
Which discontinuity lies between the upper and lower crust?
Conroad
Which discontinuity lies between the crust and mantle?
Mohorovicic
Which discontinuity lies between the upper and lower mantle?
Repetti
Who proposed the continental drift theory?
Alfred Wegener [1915]
According to the continental drift theory, 250 million years ago there was one big continent called Pangea, surrounded by one big ocean called _____.
Panthalassa
The continental rift cut Pangea from East to West, creating _____ in the North and ____ in the South.
Laurasia, Gondwalaland
What was the sea called between Laurasia & Gondwalaland?
Tethys
Who proposed the sea floor spreading theory?
Harry Hess
Name an example of a transform fault boundary.
San Andreas fault
Mid oceanic ridges are formed by _____ plate boundaries.
Divergent
Examples of exogenetic forces
Weathering and erosion
- factors affecting surface of the earth from outside
Examples of indogenetic forces
Volcanoes, earthquakes, landslides
Examples of diastropic forces
Mountains, plateaus, plains, lakes, faults
- aka constructive forces
- include vertical and horizontal movements
- operate slowly; effects visible in million years
_____ is the strictly vertical movement of a continent forming gentle arches and structural basins.
Epirogenic movement/force
- falls under diastropic forces
_____ processes involve mountain building through severe folding and affect long and narrow belts of the earth’s crust.
Orogenic
- aka tangential forces
- moving in opposite direction: tensional/divergent force; create faulting & cracking
- moves together: compressional/convergent force; create folding & warping
