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How did Perseverance Slow Down?

News Source: Success! NASA's Perseverance rover has just landed on Mars Frequently Asked Questions - NASA Mars Touchdown! NASA's Perseverance rover lands on Mars to begin hunt for signs of ancient life

Touchdown! No, not that kind. We’re talking about the touchdown of Perseverance on Mars, which is one of the first steps of our third Mars rover’s mission. So how exactly did Perseverance make a perfect landing when every control we send from Earth is delayed by 11 minutes? That’s what we’re going to go over in this article. 

First of all, what did Perseverance need to accomplish to be successful? Well, it had to slow down from 12,100 mph to zero in the span of seven minutes, so that the rover wouldn’t completely explode upon reentry. If that wasn’t hard enough, Perseverance also had to find the landing spot that had been picked out ahead of time-- Jezero Crater. Not only that, but Perseverance had to land on its feet so that it could wheel around and use all the cool tools we gave it. 

So, let’s find out how that worked. 

The easiest way to slow down a spacecraft reentering the atmosphere is the atmosphere itself. Just the pressure of the air brought Perseverance speed from 12,000 to 1,000. A thousand miles an hour is still super fast, so the next trick in Perseverance book was a parachute. This parachute had something special on it, and I encourage you to google it and find out what. However, for the sake of time, we’ll focus on the mechanics. This parachute is 70.5 feet across, which is about the same length as a five-story building’s height. The parachute slowed Perseverance all the way down to 200 miles an hour, which is better, but still fast enough to make nearly 3 billion dollars worth of equipment go SPLAT on Mars. 

The final step in this slowing-down mission is called a sky crane, and no, it’s not a flying bird that gently lands Perseverance on Mars. The real sky crane, though, is almost as far-fetched. 

Basically, a sky crane is a jetpack that lowers the rover from a string onto the ground. It might sound crazy, but it worked! The sky crane lowers a tether cord attached to Perseverance as it stays in the air on its own power. This allows the rover to slowly reach the ground, without using rockets to slow its fall and kick up dust in the process. After its job is done, the sky crane goes out in an explosion, way up in the atmosphere. 

So that’s how Perseverance landed, the good, the bad, and the crazy. It just goes to show that if we put our minds to it, we can accomplish anything. Now, if you’re not tired of space yet, maybe lookup Perseverance’s robotic arm, which debuted pretty recently!

Picture Source: nationalgeographic.com