Comet, Asteroids, Meteors, and Moons

Comets, Asteroids, Meteors and Moons

            A comet is a small, icy celestial body that orbits around the sun. It is made up of a nucleus. Nucleus is made of solid, frozen ice, gas and dust. A gaseous coma is made of water vapor, CO2, and other gases, and a long tail made of dust and other gases. The tail develops when the comet is near the Sun. Its long tail that always points away from the sun, because of the force of the solar wind. The tail can be up to 250 million km long. Comets are only visible when they're near the sun in their highly eccentric orbits.

            Asteroids are rocky and metallic objects that orbit the Sun but are too small to be considered planets. They are known as minor planets. Asteroids range in size from Ceres, which has a diameter of about 1000 km. Sixteen asteroids have a diameter of 240 km or greater. They have been found inside Earth's orbit to beyond Saturn's orbit. However, are contained within a main belt that exists between the orbits of Mars and Jupiter. Some have orbits that cross Earth's path and some have even hit the Earth in times past.

            The term meteor comes from the Greek meaning phenomenon in the sky. It is used to describe the streak of light produced as matter in the solar system falls into Earth's atmosphere. This typically occurs at heights of 80 to 110 kilometers which is 50 to 68 miles above Earth's surface.  A meteoroid is matter revolving around the sun or any object in space that is too small to be called an asteroid or a comet. Even smaller particles are called micrometeoroids, which includes any interstellar material that should happen to enter our solar system. A meteorite is a meteoroid that reaches the surface of the Earth without being completely vaporized.

            The Moon is the most noticeable object in the night sky. If you observe it for several days, you will no doubt notice that its appearance changes, most of the time. One possible explanation that comes to mind is that the dark part we see on the Moon is the shadow that the Earth casts on it. If this were true, the Moon should be in its new phase when it at its farther from the Sun. We know when this happens, because then the Moon rises at the same time as the Sun sets. Besides, if the Moon passes through the Earth's shadow every month, then when it is at the opposite side of its orbit it should get directly in between the Sun and the Earth, producing a solar eclipse much more often than it actually happens.

            All of these words, Comets, Asteroids, Meteors, and Moons all have different meanings in them. They might come from the same place but they still are all different in some way shape or form.