Our image web pages all have this great map feature (click the image to the right for an example). (It’s been there for a while, so you may have noticed it already.) If you scroll down to the bottom, below the Observation Toolbox, you’ll see a mini context map from Google maps for the specific image whose page you’re viewing. It’s so useful to be able to see the HiRISE footprints placed on a broader view of Mars, showing the surrounding geology. Plus, you can pan and zoom around in the map. Way cool.

There are 3 different maps available: Elevation, Visible, and Infrared. I’m not 100% certain which maps they’re using, but these are my guesses from comparing maps in JMARS, one of the tools we use for targeting. (JMARS is publicly available, by the way, and we recommend using it! Especially since it’s got an awesome HiRISE stamp layer now… but that’s another post!)

	Elevation = Colorized MOLA (Mars Orbiter Laser Altimeter) – I find this the most useful map to orient myself on the planet when I zoom pretty far out. The map isn’t very high resolution, but large global-scale features are easily identifiable.
	Visible = MOC (Mars Orbital Camera) wide-angle map. In this example, the visible map is clouded over by bright haze. That’s actually typical for this region – because it has such a low elevation, clouds form there during most of the year.
	Infrared = THEMIS (THermal EMission Imaging System) daytime IR – these maps are high-resolution, so they’re good for close-in context. They’re harder to interpret, though, because most people aren’t used to looking at infrared (IR) images. IR observations measure the temperature of the surface, not albedo (brightness/darkness) like a regular visible-light image. You do see shapes in daytime IR, like you would see in a visible image; shapes are detected because shadows are darker (and thus cooler) than sunlit areas. In addition, though, you can also get an idea of the type of material in an IR image. For example, dusty areas will be brighter in daytime IR images because they heat up faster during the day. Rocky areas will be darker, because it takes them longer to warm up from the cold night. (This article has a good explanation of this, using White Rock as an example.)

Using these maps, I was able to figure out that the “enigmatic terrain” in the above picture (PSP_009548_1420) is in the western part of Hellas Basin, which is a large, deep depression in the southern hemisphere of Mars. I could also tell it’s part of a larger isolated patch of this type of stuff, which seems to run concentrically along the inside of the basin rim. In this case I could have figured some of that out from the caption and the coordinates, but this is more fun.