Page 113 - SST Class 06

Do you think that if you were on the moon’s surface
you could speak to anyone as easily as you do on the
earth or see a picture in the same colours as on the
earth?
During day time, the temperature on the Moon
reaches 108°C and at night it falls to (–150°C).
These conditions make normal life impossible on
the Moon. We can only live there if we put up
special shelters for ourselves, with heating and an

The Earth as Seen from the Moon artificial atmosphere.
The Moon’s surface consists of hills, craters and
The Moon takes about 27 days to make one
basins. The largest crater is known as Bailly
revolution around the Earth. It takes the same
(‘field’ of ruin). It covers an area of about 67,300
number of days to complete one rotation around
square kilometre. The footprints left by the
its axis. Due to this, only one face of the Moon is
astronauts on the Moon will not erode since there
visible from the Earth and we get to see different
is no wind or water on the Moon. Only a meteor-
shapes of the Moon on different days of the
ite hit will erase them. Nothing can grow on the
month.
Moon because there is no air, soil or water.
The Moon is the sixth largest satellite in space.
Phases of the Moon
The largest satellites are Jupiter’s moons –
Ganymede and Callisto, Saturn’s Titan and When the Moon appears like a circular disc, it is
Neptune’s Triton. called the full Moon. The full Moon day is called
‘poornima’ in Hindi. When no Moon is visible in
The first spacecraft from the Earth to send black
the sky, it is called the new Moon. When the
pictures of the far side of the Moon was Luna 3
Moon appears like a sickle, it is called the cres-
in October, 1959. The American Astronaut Neil
cent Moon. Sometimes, the Moon appears like a
Armstrong became the first man to step on the
semicircle. The full Moon appears once in a
Moon on 20th July, 1969.
month.
So far, 12 persons have visited the Moon. The
The Moon has no water or air. The climate of the
last man was Eugene Cernan who visited the
Moon is very harsh and is not suitable for life.
Moon in December, 1972. The astronauts have
There are lots of hills and craters on the surface
brought back to the Earth 380 kg of the Moon
rocks and soil. These most expensive rocks of all
time were distributed to laboratories around the
world for scientific study. A mirror left on the
Moon’s surface helped scientists measure the
distance to the Earth (3,76,275 km), to an exact
degree of accuracy. Scientists have also mea-
sured the Moon’s mass and found that the
Earth’s mass is 81 times greater than that of the
Moon. Here is no air, water or atmosphere on
the Moon. Phases of the Moon

Social Science-6 113