• About Asteroids
  • Asteroids in the News

    Asteroids are material left over from the formation of the solar system. One theory suggests that they are the remains of a planet that was destroyed in a massive collision long ago. More likely, asteroids are material that never coalesced into a planet. In fact, if the estimated total mass of all the asteroids was gathered into a single object, the object would be less than 1,500 kilometers (932 miles) across - less than half the diameter of the Moon.

    Thousands of asteroids have been identified from Earth. It is estimated that 100,000 are bright enough to eventually be photographed through Earth based telescopes.

    Much of our understanding about asteroids comes from examining pieces of space debris that fall to the surface of Earth. Asteroids that are on a collision course with Earth are called meteoroids. When a meteoroid strikes our atmosphere at high velocity, friction causes this chunk of space matter to incinerate in a streak of light known as a meteor. If the meteoroid does not burn up completely, what's left strikes Earth's surface and is called a meteorite. One of the best places to look for meteorites is the ice cap of Antarctica.

    Of all the meteorites examined, 92.8 percent are composed of silicate (stone), and 5.7 percent are composed of iron and nickel; the rest are a mixture of the three materials. Stony meteorites are the hardest to identify since they look very much like terrestrial rocks.

    Since asteroids are material from the very early solar system, scientists are interested in their composition. Spacecraft that have flown through the asteroid belt have found that the belt is really quite empty and that asteroids are separated by very large distances.

    The impact of a large asteroid can be truly catastrophic. For example some believe that the object that smashed into the Yukatan Peninsula 65 million years ago was the event that wiped out the dinosaurs. The Gulf of Mexico may mark the crater that it left behind. The asteroid that would have hit there would have been between 10-20 miles across. The hole in created was about 20 miles deep. It was converted instantly in white hot vapor as was its target and its surrounded areas.

    A large asteroid hitting the earth would create debis that would crash down in neighboring areas. It would throw dust into the earth's atmosphere circling the globe, dimming the sunlight, ruining agriculture year round, probably ending civilization as we know it.

    At this point in time NORAD has a limited number of people monitoring the skies for asteroids. An asteroid would come in quickly. Asteroids must be tracked.

    Space Guard is an international network of telescopes where people work together to track asteroids and divert them from hitting the earth. Blowing up an asteroid is not the answer as large pieces still would impact on the earth and do lots of damage anyway.

    The Earth is continually encountering interplanetary debris of various sizes. Although the rarity increases with size, we know there are asteroids big enough to cause a catastrophe if they collided with the Earth. Because of the perturbing influence of the major planets, the asteroid orbits tend to "wander", and the calculation of whether (or when) a particular object might impact the Earth may require extremely accurate knowledge of the orbit, such as can be provided by radar observations.

    The solar system has a large number of rocky and metallic objects that are in orbit around the Sun but are too small to be considered full-fledged planets. These objects are known as asteroids or minor planets. Most, but not all, are found in a band or belt between the orbits of Mars and Jupiter. Some have orbits that cross Earth's path, and there is evidence that Earth has been hit by asteroids in the past. One of the least eroded, best preserved examples is the Barringer Meteor Crater near Winslow, Arizona.



    Ida, like Gaspra, is an S-type asteroid, meaning that it is a reddish object composed of a mixture of the minerals pyroxene, olivine, and iron. Approximately one-sixth of all known asteroids fall within the S-type category. Gaspra and Ida like other S-class asteroids are the parent bodies of some types of basaltic meteorites. The Galileo sent back pictures of main-belt asteroids (Gaspra and Ida) during the mission's cruise to Jupiter.


    There are 32 Hilda asteroids. CLICK HERE

    These are stable asteroids with no sign of chaotic behavior.

    EROS - ASTEROID #433

    An asteroid named Eros is rocketing through space. It has come within 14 million miles of earth. This asteroid is not due to smash into the earth, though there are about 1,700 out there that astronomers say could hit the earth causing a global disaster. Many Dooms Day theories state that the earth will be hit by an asteroid by the end of the 20th century causing global distruction.


    There is a large asteroid belt orbiting between Mars and Jupiter, with the possibility that a planet once existed there. Main-belt asteroids, those which orbit between Mars and Jupiter, are thought to be the source of meteorites and other near-Earth objects. Studies of main-belt asteroids provide unique opportunities to enhance understanding of the geophysical, geological, and geochemical processes that led to the formation of the solar system. The Ceres Asteroid is the largest in the asteroid belt.