They may be changed because they may find evidence of some thing that will change their perspective on things.
Explanation:
Constellation: The complete sky has been divided in 88 different areas, in a way we have divided Earth in countries, not necessarily having same shapes and size. These 88 areas are known as constellations. These contains a lot of stars. When we join the brightest stars together we can imagine a shape out of them which is called as Asterism. Most of the people are unaware of this difference. Some of the famous constellations are Orion, Taurus, Gemini, Hydra, Ursa Major etc.
When an astronomer says that there is a comet is in the Orion, he means that a comet is in the boundaries of Orion constellation.
The normal force acts to counter the gravitational force, that is the upward direction.
When an object is acted on by an unbalanced force, then that object will accelerate.
The statements that correctly compare the gravitational force with the electrical force are the following:
-The gravitational force can be attractive.
-The electrical force can be repulsive.
-The electrical force can be attractive.
-Any two objects experience a gravitational force between them.
