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8. Waning Crescent : The moon

appears to be partly, but less
than one-half illuminated
by direct sunlight.

But what about the moon

during day time, where does
it disappear? Why can’t we see
the moon and other bright tiny
objects? It happens because the
light of the sun is so bright that it

Waning Crescent does not allow us to see the less
brighter objects of the night sky.

other CeleStial BoDieS

4. aSTeroidS

Asteroids are smaller than any of the planets and only a few have
a diameter of over 30 km. They are also called planetoids or minor
planets. One asteroid called Ida has a tiny Moon of its own. This is
the smallest known satellite in the solar system while Ceres is the
largest one.

5. CoMeTS Asteroid

The celestial objects which revolve around the sun in long elliptical
orbits are called comets. When a comet reaches near the sun, it
starts glowing and develops a long tail that always streams away
from the sun.

The most famous comet is the Halley’s comet which was predicted
and studied by Edmund Halley. Halley’s comet appears after every
76 years.
Halley’s Comet

6. MeTeorS and MeTeoriTeS
Meteors are small pieces of rocks which revolve around the sun.
Sometimes you have seen shooting stars (bright streaks of light) in
the sky, actually they are meteors.

Meteors
Social Studies-6 9