Telescope is a device for "seeing faraway things as though
nearby". Galileo invented the telescope, in the early 1600s,
he even discovered four of Jupiter's moons. We can see some planets without a
The planet Mars is the fourth planet from the sun and is
called as "the Red Planet," can be seen at
night from the Earth without a telescope. Another planet Jupiter that is the
largest among the nine planets can also be seen without a telescope. From Earth it
looks like a star.
Telescopes are constructed with giant mirrors or lenses so that they can collect more light than the human eye can see on its own. How a telescope collects and concentrates light?
The convex lens or the concave mirror present in the
telescope collects light. The bigger the convex lens or the concave mirror, the
more light it can collect. The more light it collects, the fainter the objects
it allows us to see. The human eye has a convex lens, which can only collect a
small amount of light because the lens is small. Telescopes allow us to see more
because their mirrors and lenses can collect more light than the human eye can
collect on its own.
Therefore, astronomers use several light-gathering tools to
probe the universe from our planetary neighbors to the deepest regions of space