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NASA flies spacecraft all over the solar system, and orbits the Earth.

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How do we communicate with them when they're so far away?

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Let's find out from an expert.

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Hi, I'm Jim Green, Chief Scientist at NASA and this is the Gravity Assist Podcast.

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In this season of Gravity Assist, we'll go behind the scenes at NASA and we'll hear from

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the scientists and engineers and others who make these amazing space missions happen.

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I'm here with Nacer Chahat, and he is the Senior Antenna and Microwave Engineer with

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NASA's Jet Propulsion Laboratory out in Pasadena, California.

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Well, you know, communication with our surface assets on Mars is kind of complicated.

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You know, when we landed Curiosity, I don't see it carrying a big truck with a big dish behind it.

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So how do we communicate back and forth with, with our surface assets, like Insight, like Perseverance, like Curiosity?

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Yes, so we have two concepts to do so.

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The first one is to communicate with the orbiter.

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So we have orbiters around Mars which we can they are dedicated for science, but for a

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critical event like that, we can use them to relay the data to Earth.

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And we also have on these landers and rover, high-gain antennas that allow us to communicate

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directly with Earth but a lower that rate.

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So it's really a trade off, when we should be using the orbiter or when we should be

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using the high-gain antenna.

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Most of the time, we end up using the orbiter because it allows us to transmit the science much faster.

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Well, you know, we're flying a helicopter on Mars for the first time.

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And we call that Ingenuity.

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Did you get involved in that?

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And what's your role?

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My contribution was with the telecommunication subsystem, to ensure that the rover can send

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commands to the helicopter, and the helicopter can send images or telemetry back to the rover.

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So, I worked on the antenna design and also worked on the system engineering.

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Wow, that sounds really difficult because this is a very small vehicle.

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What's that antenna look like?

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I don't remember seeing it.

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Does it stick out?

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Or is it part of it goes up to the top or, where's it at?

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Yeah, so on the top of the helicopter, there is a solar panel, which allows us to recharge our battery.

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And we decided to locate the antenna on this surface, because this is what provided the

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largest area to use as a reflective surface.

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So this is the simplest type of antenna that you can ever use.

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This is called a monopole.

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So monopole is basically a single wire.

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This type of monopole antenna are being used when you need to communicate omnidirectionally.

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Meaning, we need to communicate this with the same capabilities in any direction.

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It's very small - it's about five to six centimeter

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So it sounds like though the Ingenuity communication is only with, with Perseverance, and then

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it's up to Perseverance to package that data and then send it up to an orbiter which then

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relays it back to Earth.

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That's exactly it.

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Altimeter data confirms that Ingenuity has performed its first flight of a powered aircraft on another planet!

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When I saw the first flight, I couldn't help but think of all of those hours working really

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hard to solve technical problems.

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This achievement is absolutely historical and I am happy I got to contribute.