This artist's concept of NASA's Mars Reconnaissance Orbiter features the spacecraft's main bus facing down, toward the red planet.

The large silver circular feature above the spacecraft bus is the high-gain antenna, the spacecraft's main means of communicating with Earth.

The long, thin pole behind the bus is the antenna for the Shallow Subsurface Radar instrument (SHARAD). Seeking liquid or frozen water, this instrument will probe the subsurface using radar waves at frequencies of 15 to 25 megahertz, "seeing" in the first few hundred feet (up to 1 kilometer) of Mars' crust.

The large instrument covered in black thermal blanketing in the center is the High Resolution Imaging Science Experiment camera (HiRISE). It will provide the highest-resolution images ever taken from Mars orbit.

The Electra telecommunications package is the gold-colored instrument directly left of the high-resolution camera. It will act as a communications relay and navigation aid for Mars spacecraft.

To the right of the high-resolution camera is the Context Imager (CTX).