NASA extends the Mars helicopter mission, testing it for actual mission ops

Droning on and on is usually boring, but in this case it's actually pretty exciting: NASA is extending the mission for the Mars Ingenuity helicopter drone! And it's entering a new phase, too, going from technology demonstration to operations demonstration, meaning it's not just seeing if the new technology works on Mars at all, but actually showing that it can be used to aid in the exploration of the planet.

This new mission phase starts with Flight number six, which should take place in a couple of weeks. On Friday Ingenuity flew for the fourth time off the surface of Mars, climbing to an altitude of 5 meters and then sliding south for over 130 meters before returning to its spot near the Perseverance rover. It was in the air for about 117 seconds.

Here's a cool video showing its shadow as it traveled over the ground during its previous, third flight:

The blades don't seem to move due to the way the images were taken; the shutter is synched to the blade movement. The bright spot around the shadow is due to the opposition effect: The lack of shadows from rocks and other irregularities on the surface makes it look brighter, plus some dusty surfaces tend to reflect more light straight back in the direction the light came from, making it look brighter around the shadow.

A fifth flight is planned in the next few days, where Ingenuity will take a one-way trip to a new landing site it visited on flight four. For a few days after that Perseverance will travel south to join up with it again.

The Perseverance rover took this image of the helicopter Ingenuity (arrowed) as it flew south 133 meters away and returned on its fourth flight, which took place Friday morning, April 30, 2021. Credit: NASA/JPL-Caltech

Assuming that flight goes well — and all four have gone flawlessly so far — the new operations phase will begin. The flights are still being planned, but the idea is for it to fly over spots the rover will travel to get stereo images so that digital elevation maps can be made, and look at spots nearby the rover can't reach to get a better overview of the area. These images won't be critical for the rover operations, but they'll be a nice bonus to the science Perseverance will do while it's there. It may land near the rover, or travel on to where the rover's headed to check ahead and then await Perseverance's arrival.

It's hard to overstate what an amazing success this is. Flying on Mars is hard. The gravity is only about 1/3^rd that on Earth, making it easier, but the air is far thinner, only 0.6% the pressure at Earth sea level, equivalent to being three times higher than Mt. Everest on Earth! To get the needed lift the helicopter is lightweight (about 1.8 kilograms, so 4 pounds on Earth, and about 1.5 pounds on Mars), the blades are over a meter long, and they spin at over 2500 RPM (40+ times per second) to get off the ground.

Schematic of the Mars drone copter Ingenuity. Credit: NASA/JPL-Caltech

The drone is also almost entirely autonomous (NASA put up a great article written by the Ingenuity Chief Pilot on how this all works). It's given a series of commands sent from Earth, but these are not in real-time since Mars is 300 million km from Earth right now, and even radio signals traveling at the speed of light take almost 17 minutes to get there (plus another 17 to get back). So it takes off, flies around, comes back, and lands all by itself, as well as taking images, communicating with the rover, checking its own battery levels, and more.

What's dead simple on Earth is fantastically complicated on Mars. The folks at NASA/JPL just make it look easy. It ain't.

Ingenuity took this shot of the rover Perseverance (upper left, inset zoom below) as it flew for the third time on Mars on April 25, 2021. At bottom is a diagram showing the location of rover tracks and the site where the rover landed on Mars on February 18, 2021. Credit: NASA/JPL-Caltech

The first flight was on April 19, and was a simple up-and-down, and each successive flight has been longer and more complex. Now, with mission operations starting, it'll be even more so. The flights will be more spaced out, happening every week or two, and they'll be scheduled to avoid interfering with Perseverance's own operations. The Ingenuity team on Earth will reassess the drone's status after a month or so, and this phase will be completed no later than August.

It's too early to speculate about what will happen after that; NASA could extend the mission again (which has happened several times to rovers on Mars; they tend to work well outside the limits of their warranties) or it could decide to shut it down in favor of the rover's mission. We'll see. I think it's clear what everyone hopes for.