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• Duttada, an amateur scientist, can’t stay away from the keen eyed Dibya Chakshu ( his telescope) for long.
• Duttada's secret ambition was to discover a new Comet
• One night, Duttada detects a new comet.
• Thereafter it is named after the discoverer as the ‘’Comet Dutta’’.
• Indian Institute of Astrophysics conforms his findings.
• His wife Indrani Debi, wishes he hadn’t found the comet.
• A British scientist writes a paper based on Duttada’s discovery.
• A conference of international experts is convened to yield a clue to the cosmic puzzle.
• Duttada and the British defence Science Advisor have a meeting over the impending calamity.
• The problem was that the Comet Dutta was to collide with the earth.
• The experts calculated that the bulk of destructive nuclear power available on earth would be needed to achieve this mammoth task.
• The project ‘’LIGTH BRIGADE’’ was the name of the space mission to stop Comet Dutta from collision with the earth.
• Duttada returns home to a warm welcome and a ceremony.
• On November 18 Duttada receives a secret message, indicating the success of the mission and then he rushes to the sweet shop.
• On 15 December the Comet Dutta passes the earth at a distance of 80,000 km.
• Duttada believed in scientific logic but there are many people who believe in superstition.
• His wife believed in superstition and concluded the collision was avoided because of the ‘yagna’ perfomed by her grandson.
• An Indian astrophysicist• A proponent of steady state cosmology• He developed with Sir Fred Hoyle the conformal gravity theory,
commonly known as Hoyle–Narlikar theory
• Born: July 19, 1938, Kolhapur• Education: Banaras Hindu University,
University of Cambridge• Awards: Padma Bhushan, Padma
Vibhushan• In 1966 joined Institute of Theoretical
Astronomy in Cambridge University• In 1972 joined as professor of Theoretical
physics at the Tata institute of Fundamental Research, Mumbai
• In 1989 took charge as Founder-Director of Inter university centre for astronomy & astrophysics (IUCAA), Pune
• Comets are small icy bodies
• Travel past the Sun
• Give off gas and dust as they pass by
• Comets have a nucleus, coma and tail
• Nucleus (very small, about 10 km across) rock & ices (mostly H2O and CO2 [dry ice], some methane CH4 & ammonia NH3)
• Coma (103 to 105 km in diameter) is gaseous & is a cloud of evaporated ices and ions. As comet approaches Sun ices sublime, change from solid to gas, dust grains loosen and move away
• Tails (105 km to 1 AU long), always points away from the Sun. Solar wind (steady stream of solar particles) pushes gas away; dust continues to orbit Sun.
• Small bodies
• Believed to be left over from the beginning of the solar system billions of years ago
• 100,000 asteroids lie in the asteroid belt between Mars and Jupiter
• Largest asteroids have been given names
• Asteroids show up as streaks on photos
• Since they orbit the Sun, they are observed to move with respect to the stars
• Asteroids are typically cratered and irregularly shaped
• Composition of Asteriods are:
• Carbonaceous—containing carbon
• Rocky—mostly silicates
• Metallic—iron and nickel rich
• Asteroids show up as streaks on photos
• Meteors burn up in the atmosphere; meteorites don’t; impacts can and do happen
• Meteor Crater, Arizona
• 50,000 years old
• Projectile was 50 meter diameter, metallic asteroid
• Crater diameter is 1.2 km, 200 m deep
Irons Stony-Irons
Chondrites Carbonaceous Chondrite
Achondrite
• An iron meteorite 100 feet across and 70,000 tons slammed into the Earth at about 43,000mph in the Arizona desert near Flagstaff 40,000 years ago.
• Barringer Crater is 4,100 feet wide and 571 feet deep.
• Our Galaxy is a collection of
stellar and interstellar matter
– stars, gas, dust, neutron stars, gas, dust, neutron
stars, black holesstars, black holes – held
together by gravity.
• 1610 -Galileo discovered the
Milky Way is comprised of
many stars
• Our solar system is made up of:
• Sun
• Nine planets
• Their moons
• Asteroids
• Comets
• The inner four rocky planets at the center of the solar system are:
• Mercury
• Venus
• Earth
• Mars
• The outer planets composed of gas are :
• Jupiter
• Saturn
• Uranus
• Neptune
• Orbit height: 569 km• Launch date: April 24,
1990• Speed on orbit: 7.5
km/s• Power: 2,800 watts
• The Hubble Space Telescope is a space telescope that was carried into orbit by a Space Shuttle in 1990 and remains in operation
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