SCIENCE
EARTH SCIENCE
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
It is orbiting around a star
|
|
|
It has sufficient mass to assume hydrostatic equilibrium
|
|
|
It has no neighbourhood around its orbit
|
|
|
It has to be round or spherical enough to be called a planet
|
Detailed explanation-1: -It says a planet must do three things: It must orbit a star (in our cosmic neighborhood, the Sun). It must be big enough to have enough gravity to force it into a spherical shape. It must be big enough that its gravity cleared away any other objects of a similar size near its orbit around the Sun.
Detailed explanation-2: -The correct answer is ‘Distance’. The given passage talks about ‘Why Pluto is not a Planet’. As it is mentioned in the passage that ‘to be a planet, an object must be large enough to have cleared the path of its orbit of other debris orbiting the sun. ‘
Detailed explanation-3: -So, the three criteria of the IAU for a full-sized planet are: It is in orbit around the Sun. It has sufficient mass to assume hydrostatic equilibrium (a nearly round shape). It has “cleared the neighborhood” around its orbit.
Detailed explanation-4: -Discovered 80 years ago, Pluto was considered the last planet in the solar system until 2006. On that date, the International Astronomical Union defined new rules for classifying planets: the body must be spherical; revolve around the sun; and have free orbit, with no other objects in its path.