On the other hand, the majority of comets are in the farthest reaches of our Solar System: either 1. Some scientists think asteroids formed much closer to the Sun, where it was too warm for any ices to remain solid, while comets formed farther from the Sun and were therefore able to retain ice. However, other scientists think that the comets that are now in the Kuiper Belt and Oort cloud actually formed in the inner Solar System, but were then flung out from the gravitation effects of the giant planets Jupiter and Saturn.
When comets approach the Sun, some of their ices melt. When the ices in comets begin to melt and other materials vaporize from the heat from the Sun, this forms a glowing halo that extends outward from the comet as it sails through space. The ice and compounds like methane and ammonia develop a fuzzy, cloud-like shell called a coma. Tails always points away from the Sun. This seems to happen when the asteroid has been hit or pummeled by other asteroids and dust or gas is ejected from their surfaces, creating a sporadic tail effect.
Another difference between asteroids and comets is in their orbital patterns. Asteroids tend to have shorter, more circular orbits. Comets tend to have very extended and elongated orbits, which often exceed 50, AU from the Sun. For millennia, the sight of a comet elicited fear and awe. Ancient astronomers believed comets foretold the death of princes and the outcomes of wars. Modern astronomers know comets are the ice-clad leftovers from the material that formed our solar system billions of years ago.
Astronomer Fred Whipple was the first to describe comets as dirty snowballs, or icy conglomerates of frozen gases and dust. The snowball makes up the central nucleus of a comet, which is often less than a few miles across, according to NASA. When a comet nears the sun, the nucleus warms up and the ice begins to sublimate from solid to gas.
This produces an atmosphere surrounding the comet that can grow to thousands of miles in diameter, called a coma. Radiation pressure from the sun blows away the dust particles in the coma to produce a long, bright dust tail.
A second tail is formed when high-energy solar particles ionize the gas, creating a separate ion tail. The difference between the composition of asteroids and comets is likely due to how and where they were born, wrote Britt Scharringhausen , a professor of astronomy at Beloit College in Wisconsin.
At the center of the nebula, the sun was being born through gravitational collapse. The study of meteors is called meteoritics , and a person who studies meteors is called a meteoriticist. The title of meteorologist was already taken by those who study weather and weather patterns. This might seem strange, but it makes more sense when you realize that the word meteor was once used to refer to any atmospheric phenomenon—like hail or a hurricane. Meteorologists know quite easily the difference between weather and climate.
Do you? Learn more about them here. Meteorites tend to be bigger than the meteors that burn up before making it to the surface.
This makes sense, because the bigger ones have more to get burned away on their way to the surface, while the smaller ones disintegrate into nothing. A meteorite might look like a fireball as it crashes toward Earth, but it eventually cools. The -ite ending is often used in the names of rocks and minerals, such as anthracite. Meteorite impacts can be pretty violent.
The large Chicxulub crater in Mexico is thought to be from the meteorite strike that caused the extinction of many dinosaurs. The biggest impact crater on Earth is the Vredefort crater in South Africa—it was originally miles across. In more casual use, meteorite is also sometimes used as a synonym for meteoroid —a rock traveling through space. Technically speaking, though, the space rocks that reach the ground are typically called meteorites.
Meteoroids , meteors , and meteorites are really names for space rocks at different stages. The ones floating around in space are meteoroids. A meteor shower is what happens when a lot of meteors enter the atmosphere during a relatively short period of time. Many people enjoy meteor showers because they allow you to see many meteors at once. Asteroids typically consist of rocks or metals. In disaster movies, the big space rock that might destroy the entire planet is usually an asteroid.
The collection acts as a meteorite library for scientists. By studying different types of meteorites, scientists can learn more about asteroids, planets and other parts of our solar system. Because asteroids formed in the early days of our solar system nearly 4. Asteroid or Meteor: What's the Difference? The Short Answer:.
More about asteroids, meteors, and comets! What Is an Asteroid? What Is a Meteor Shower?
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