Our solar system continuously showers planets with asteroids and meteors. Each year, almost 50 thousand tonnes of asteroid and space debris hit the earth’s atmosphere where most of it burns up. Few of the pieces ever make direct contact with planets. And when they do, it is usually a catastrophic event, both for the planet and the asteroid.
Wait! What’s the difference between an asteroid and a meteor?
We are glad you asked! An asteroid is a large rock or piece of metal that orbits around the Sun. When pieces of asteroids break off, they are called meteorites. When these meteorites enter the earth’s atmosphere, they vapourize and form bright streaks of light, called meteors.
When have we seen them?
Recently, 3 asteroids crossed paths with Earth. Observatories from around the world focused their telescopes on these visitors. Fortunately, they were anywhere between 1 lakh 50 thousand kilometres to 30 lakh kilometres from our planet. That sounds like a lot, but on a universal scale, the distances between the Earth and these passing asteroids are enough to alarm astronomers.
Here’s a term: NEO. Any objects that are close to the earth are called Near Earth Objects (NEOs).
Asteroid 2019 SM8 was a mere 1 lakh 59 thousand kilometres from Earth, discovered only 2 days before the encounter. Asteroid 2019 SE8 and 2019 SD8 skimmed passed Earth at 11 lakh kilometres and 5 lakh kilometres respectively. They were no bigger than an SUV, yet direct contact could have been dangerous.
How do they start targeting planets?
Asteroids are nothing but wandering balls of dust and ice. Sometimes the Sun’s gravitational pull changes an asteroid’s course, hurtling it towards planets. In 1908, a building-sized asteroid caused an explosion equivalent to 1000 atomic bombs in Russia.
Shouldn’t we track NEOs? Yes we should! Asteroid collisions have had devastating effects on planet Earth. Throughout history, our planet has had many such events leading to complete annihilation of many biological species.
So what’s the problem? Near-Earth Objects are difficult to track because they move really fast, at a speed of 30 thousand kilometres per hour or more.
What can we do about this?
NASA’s Planetary Defence Coordination Office (PDCO) uses many ground and space-based telescopes to scan the skies. The idea is to detect any potentially hazardous object, track its movement and issue a warning. But this is not very precise. An impact only 2 days away doesn’t really give us any time to prepare! NASA’s Asteroids Initiative has asked for ideas and ways to defend the planet. As of now, early detection is the only way of knowing would hit us.
Can you think of some possible ways to prevent an asteroid impact? Share your thoughts in the comment section below.
Written by: Akash Dubey. Akash is a freelance writer and editor. In his free time, he enjoys reading, playing the guitar and taking long walks.