Lynn Carter

but by pulling this ground penetrating radar across the surface, you can see all of this buried stratigraphy that you wouldn't be able to see unless you went there and dug a hole.

And also this is useful because you can see the stratigraphy over a long or large area, as opposed to if you dug a hole, you would probably only see a small part, or you would have to excavate a ton of material.

And so radar is very useful for that.

And again, this is used a lot for archeology or for

even things like concrete analysis in society.

So it's a pretty common technique that people use when they want to understand things that are under the surface and understand what that stratigraphy was and how things evolved through time.

So those are the two different examples of radars.

And at Mars, so far,

We haven't sent one of these on a mission, but we've sent some of these.

So this talk is going to focus on this type of example, not this.

Although this would be very cool on Mars, and hopefully someday we'll get there.

So right now, there's two radars in orbit around Mars.

So one of them is the Mars radar on the Mars Express spacecraft.

So this instrument is on a European, this is a European Space Agency mission, and it has a really long wavelength, so about 60 plus meters.

And the other one that I'm going to spend most of the time talking about is Charade.

And that's on Mars Reconnaissance Orbiter.

And like I said, that's the same spacecraft that the HiRISE camera is on.

And the frequency of this radar is 20 megahertz.

So that corresponds to about 15 meters.

So these are really long wavelengths.