Sam was gazing through a telescope and noticed a bright spot moving fast through the sky. On closer examination, he observed the spot was followed by stream of dust as it neared the sun. What did Same most likely observe?
A. An asteroid
B. A moon
C. A comet
D. A meteor
C. A comet
C. A comet
Comets are known for their bright tails and appearance of dust or gas as they get closer to the sun.
To determine what Sam most likely observed, we need to understand the characteristics of the different celestial objects mentioned: asteroid, moon, comet, and meteor.
Asteroids are rocky objects that orbit the sun, typically found in the asteroid belt between Mars and Jupiter. They do not have a visible tail of dust or gas when they travel through space.
Moons are natural satellites that orbit planets. They do not move independently through the sky but are instead seen in orbit around their respective planets.
Comets are icy bodies that also orbit the sun but tend to have highly elliptical orbits that take them far from the sun and then bring them back closer. As comets approach the sun, they heat up, and the heat causes the ice to vaporize, producing a visible tail of gas and dust that streams behind them.
Meteors, on the other hand, are smaller rocky or metallic objects that enter the Earth's atmosphere and burn up, producing a streak of light commonly known as a shooting star.
Based on the provided information, the bright spot moving fast through the sky and the stream of dust observed near the sun suggest that Sam most likely observed a comet (option C). The tail of dust or gas is a distinct characteristic of comets when they approach the sun and the heat causes sublimation of their icy materials.