Asteroids are stony asteroids with unusual shapes that circle our Sun. They resemble stars when seen via a telescope from Earth, which is how they earned their name. The asteroid is a celestial body.
The majority of asteroids are around 300 km (186 miles) in diameter. Ceres is the biggest asteroid known to us, with a diameter of 940 km (584 miles) (Chaisson and McMillan, 2005).
The majority of asteroids are found in the asteroid belt, which is positioned between the orbits of Mars and Jupiter. Because of Jupiter’s tremendous gravitational pull, scientists think these asteroids are rocks that were never able to merge and create a planet.
The Galileo spacecraft captured this NASA photograph of Asteroid Ida (S-type) and its moon Dactyl. Ida has a diameter of 56 kilometers (35 miles), whereas Dactyl has a diameter of just 1.5 kilometers (1 mile). Ida is thought to be at least a billion years old, according to scientists. Astronomers were unaware that asteroids could have their own satellites until the discovery of Ida’s moon Dactyl.
Types of Asteroids
The composition and reflectivity of asteroids are used to classify them. C-type asteroids are the most frequent. C-type asteroids are black, non-reflective asteroids with high carbon content.
S-type asteroids are the second most frequent. These asteroids have a high silicate content and reflect much more light than C-type asteroids.
M-type asteroids, which are rich in nickel and iron, are the least frequent. These asteroids reflect a lot of light.
Will An Asteroid Hit Earth In My Lifetime?
Most of us have seen movies about an asteroid colliding with Earth, but could it actually happen?
The majority of asteroids circle Mars and Jupiter. Some asteroids, however, do penetrate the vacuity of Earth’s orbit. These are known as Near Earth Objects (NEOs) or Earth-Crossing Asteroids (ECAs).
These NEOs are known as Apollo or Aten asteroids. Aten asteroids have orbits that cross with Earth’s orbit, while Apollo asteroids have orbits that are inside Earth’s orbit (Moche, 2004). Over 2,600 of these Near Earth Objects have been found by astronomers (Chaisson and McMillan, 2005), with 624 of them classed as potentially dangerous asteroids (Maran, 2005).
There is evidence that asteroids once crashed with Earth. In truth, most scientists think that an asteroid collision with Earth was responsible for the dinosaurs’ demise. Asteroid collisions are also thought to be the origin of a few big impact craters on Earth.
Astronomers now monitor the sky for asteroids that might collide with Earth so that we can prepare or move the asteroid into a new orbit so that it doesn’t collide with us. This is just another reason why the space program is critical. With the high-tech telescopes at astronomers’ disposal, we’d know if an asteroid was heading toward Earth in plenty of time to do anything about it.
In fact, NASA’s Jet Propulsion Laboratory has a new site where you can find information on the location of near-Earth Asteroids: NASA Asteroid Watch.
There have been asteroids that have gone quite near to Earth in the recent two decades, with at least one asteroid coming within 105,000 km (65,244 miles) of Earth (Chaisson and McMillan, 2005).
The majority of these Near-Earth asteroids are quite tiny (1 km or less than 1 mile in diameter), yet even an asteroid this small might have catastrophic consequences if it struck Earth.
- Chaisson, E. and McMillan, S. (2005). Astronomy Today. Pearson Prentice Hall: Upper Saddle River, NJ.
- Maran, S. P. (2005). Astronomy for Dummies. Wiley: Indianapolis, IN.
- Moche, D. L. (2004). Astronomy. Wiley: Hoboken, NJ.
🌏 🌏 Here Are Some Popular Items for the Galaxy Lovers. Click the Images to See the Current Prices on Amazon!! 🌏 🌏