Download Section 1 - The Solar System

Published by
Pearson Education India
Authored by
Edgar Thorpe & Showick Thorpe
2. THE SOLAR SYSTEM [Section 2]
Topics Covered
2
Origin
2.1
Age
2.2
Characteristics
Slide Numbers
[2 ]
[3]
[4-22]
Question 1: First scientific system regarding the origin of
solar system was put forward by whom?
Answer: Marquis de Laplace (France) in 1796.
Extra Fact Punch
He propounded a theory: the sun is spinning rapidly as it contracted after its birth, threw off from its
centre, rings of the gaseous material, each of which condensed into a separate planet.
Question 2: We know that the Solar system formed
4,600 million years ago. By which method was the age of
solar system confirmed?
Answer: Radioactive decay.
Extra Fact Punch
By measuring such decay in meteorites, scientists learned that the Sun and the planets formed 4600
million years ago. This was confirmed by the study of moon rocks.
Question 6: Objects found further than the most distant
planet in our solar system, Pluto are?
Answer: Varuna(2000), Ixion(2001), Quaoar(2002), and Sedna(2003).
Extra Fact Punch
The nearest star is about 9,000 times farther away than most distant planet in our solar system.
Question 8: Pluto is considered as dwarf planet and was
discovered by?
Answer: Clyde Tombaugh in 1930.
Extra Fact Punch
It is now classified as a dwarf planet along with Ceres and Eris.
Question 9: Arrange different layers of Sun moving from
the innermost to the outermost layer.
Answer: Corona, Chromosphere, Photosphere.
Extra Fact Punch
Glowing surface is called the photosphere. Above the photosphere is the chromosphere, and beyond
this layer is the corona which is visible during eclipses.
Question 12: Is it possible to view Sun’s layer during total
solar eclipse? If yes name the different layers.
Answer: The Chromosphere and corona.
Extra Fact Punch
The chromosphere appears as a pinkish-violet layer with occasional prominence.
Question 14:_____ are dark irregular shaped regions with
diameters extending to tens of thousands of miles.
Answer: Sunspots.
.
Extra Fact Punch
The astronomers believe that sunspots occur when lines of magnetic forces
break through the sun’s surface.
Question 19: Sunspots group have an average life of
_____.
Answer: From 2 to 3 weeks.
Extra Fact Punch
But some sunspots group have lasted for more than a year. The record duration of the sunspot is 8
years.
Question 24: When did the Viking-1 and Viking-2
spacecrafts land on mars to study the existence of life on
the Planet?
Answer: Viking-1, landed on mars in July 1979 and Vikings-2 in September1979.
Extra Fact Punch
The experiments revealed no traces of life.
Question 26: ______is the largest satellite in our solar
system.
Answer: Ganymede.
Extra Fact Punch
Ganymede is a prominent satellite of Jupiter along with Europa and Callisto.
Question 27: ____is the biggest satellite of the
planet with ring system?
Answer: Titan.
.
Extra Fact Punch
Saturn is outer planet visible to naked eye. Ring system is made up of a variety of separate particles
which move independently in circular orbits.
Question 28: Uranus is the first planet discovered
through Telescope. Who discovered it?
Answer: William Herchel in 1781.
Extra Fact Punch
The most prominent satellite of Uranus are Miranda, Ariel, Umbriel and Titanis.
Question 29: Neptune was discovered by?
Answer: J.G Galle of Berlin in 1846.
Extra Fact Punch
Major satellites are Triton and Nereid.
Question 31: Moon takes ____days, _____hours,____
minutes and _____ seconds to complete one revolution
of the earth?
Answer: 27 days 7 hours 43 minutes and 11.47 seconds.
Extra Fact Punch
It takes 1.3 seconds for moonlight to reach the earth, whereas sunlight takes about 8
minutes and 16.6 seconds to reach the Earth.
Question 32: Neil Armstrong and Edwin Aldrin first
stepped on the surface of moon on July 21,1969? True
or False. If true then name the spacecraft?
Answer: Apollo 11.
Extra Fact Punch
A total of 12 Americans walked on the surface of the Moon during Apollo programme.
Question 33: Asteroids are also known as _______.
Answer: Planetoids.
Extra Fact Punch
The first ten minor planets include: Ceres, Pallas, June, Vesta, Astraea, Heba. There are
about 50,000 known asteroids in our solar system.
Question 35: The word ‘Comet’ is derived from Greek
letter ‘Kometes’ what does ‘Kometes’ mean?
Answer: Kometes means ‘hair –like’.
Extra Fact Punch
There are about 1,00,000 comets in our solar system.
Question 36: Halley’s comet is named after Edmund
Halley. When did it last appear?
Answer: It last appeared in 1896.
Extra Fact Punch
Halley stated that the comets were seen in 1531,1607 and 1682 ad it may reappear after 76 years.
Question 37: When is Comet ‘Smith-Tuttle’ likely to
collide with the earth?
Answer: On August17, 2116.
Extra Fact Punch
Smith Tuttle was first sighted in 1862. it travels at a speed of 60 km/sec.
Question 38: When and by whom was comet
‘Shoemaker Levy-9’ discovered?
Answer: it was discovered on March 24,1993.
By Scientists
(a) Carolyn
(b) Eugene Shoemaker
(c) David Levy.
Extra Fact Punch
Comet was around 6 miles long and weighted about 500 billion tonnes.
Question 39: ‘Aurora Borealis’ is also known as?
Answer: Northern lights.
Extra Fact Punch
The luminous occurrences in high altitudes of both hemispheres are called ‘Aurora Borealis’ or
‘northern lights’ in the northern hemisphere, and ‘Aurora Australis’ in the southern hemisphere.