Astro Bob: Make your own asteroid and hurl it at Earth

Duluth impact — This illustration, created with Asteroid Launcher, shows what would happen if a mile-wide, iron-nickel asteroid struck Duluth, Minnesota, traveling at 40,000 miles an hour at an approach angle of 45 degrees. The strike would carve a crater 17 miles (27 km) across and 2,610 feet (795 meters) deep. Buildings within 201 miles would collapse and an estimated 1.8 million people would die from the fireball alone. Fortunately, such collisions are extremely rare, occurring about every 2.6 million years.

By Bob King

January 10, 2023 at 1:28 PM

DULUTH — I grew up next to a neighbor with a gravel driveway. My friends and I used to sit in fold-out lawn chairs under the car port on warm afternoons and talk and throw stones. It was a great way to pass the time. Sometimes we'd toss the rocks at each other. You know. Boys.

There's a certain pleasure in picking up and throwing a rock. We all feel it. Who hasn't seen a child pitch a pebble into a lake and delight to the splash and plop? Now that we're adults we can throw bigger rocks. And with help from the internet, we can launch miles-wide asteroids at the Earth as though we were gods.

Duluth crater — As the fireball cools, a large crater appears where Duluth and neighboring Superior, Wisconsin, once stood. For metric users, the simulator has a metric-use link.

I recently came across a new interactive asteroid simulator that not only provides the primeval pleasure of rock-tossing but vividly demonstrates the real consequences of an asteroid impact. Created by Neal Agarwal , the Asteroid Launcher at neal.fun/asteroid-launcher lets the user pick the location of impact along with the the asteroid's size and type — stony, iron, carbonaceous and even a precious-metal-rich "gold" variety. By the way, the more metallic the body, the greater the devastation. Comets are included,too.

Asteroid Earth — This artist view shows an asteroid passing near the Earth. Although most of the larger, most threatening asteroids have been discovered, there are still plenty of smaller ones out there that could potentially impact the planet in the future.

You can also adjust the impact speed (an average asteroid impact velocity is 40,000 mph / 64,000 kph) and entry angle. After pressing the launch button, a brilliant fireball flashes before your eyes then shrinks and dims to reveal the crater left behind. The consequences are summarized in a column of frankly terrifying data that includes death toll, wind speed, earthquake magnitude, distance at which clothes catch on fire, frequency of your impact choice and more.

The interactive map lets you choose any location you like by clicking and dragging your mouse. You can even simulate particular events such as the Chelyabinsk, Russia asteroid explosion that occurred just shy of 10 years ago. Select a stony asteroid 66 feet (20 meters) across, a speed of 43,000 miles per hour (69,000 kph) and an incoming angle of 18 degrees.

Chelyabinsk meteorites — This is a tiny sample of the numerous stony meteorites that fell after the Chelybinsk meteor air burst on Feb. 15, 2013.

Thankfully, that asteroid was small enough to blow pieces in an air burst some 20 miles (30 km) above the ground. Had it been larger or its angle steeper, it would have caused far more devastation. I wanted to simulate the Chicxulub impact that led to the demise of the dinosaurs 66 million years ago, but the size limit is 1 mile (1.5 km), and that asteroid was 6.2 miles (10 km) across. To size up its might I had to use the Impact: Earth! site described at the end of this post.

Agarwal created the tool using information from scientific papers including this risk assessment and a NASA publication that modeled population vulnerability by asteroid impact. He hopes that people come to better appreciate the need to deflect troublesome asteroids before they become serious liabilities. Reading the cold, hard facts about the simulated Duluth impact woke me right up — like a stone lobbed my way on that driveway long ago.

You might also want to check out these other impact simulators:
Impact: Earth! https://impact.ese.ic.ac.uk/ImpactEarth/
Killer Asteroids killerasteroids.org/interactives/wiihmt/index.html
Down2Earth http://simulator.down2earth.eu/planet.html?lang=pt-BR (Defaults to Portuguese. Change language by clicking in upper right corner)