A bright,extended object appears in the sky one evening,visible to the naked eye.Over the next several weeks,it moves across the sky,becoming brighter as it approaches the Sun and then fainter again as it moves away.After six weeks,it fades away.This is most likely a(n):
A) supernova.
B) Earth-crossing asteroid.
C) Trojan asteroid.
D) comet.

Question

A bright,extended object appears in the sky one evening,visible to the naked eye.Over the next several weeks,it moves across the sky,becoming brighter as it approaches the Sun and then fainter again as it moves away.After six weeks,it fades away.This is most likely a(n):
A) supernova.
B) Earth-crossing asteroid.
C) Trojan asteroid.
D) comet.

Quizplus · Accepted Answer

The object's brightness and movement across the sky indicate that it is most likely a comet. Comets are icy bodies that come into the inner solar system from the outer solar system and can appear as bright, extended objects. They become brighter as they approach the sun and then fade away as they move away from it. The fact that it fades away after six weeks suggests that it has moved away from the sun and is no longer visible. Supernovae and Earth-crossing asteroids would not exhibit the same type of movement and fading, while Trojan asteroids are typically locked in stable orbits around Jupiter and do not move across the sky in the same way.

A Bright,extended Object Appears in the Sky One Evening,visible to the Naked