How does the Curiosity rover take pictures of itself without showing the selfie stick?


Many of us have seen pictures sent from Mars by the Curiosity rover. And many immediately noticed that in the photos, which are photographs of oneself, one cannot see any «selfie stick» or other instrument holding the camera. As if someone else is photographing the rover.

This gave rise to many stupid speculations, to the extent that there is supposedly no rover on Mars, and all this is being photographed somewhere in the desert in Nevada and color filters are applied to make it look like Mars.

These speculations, of course, are completely groundless, but let’s figure out how it turns out that the camera seems to be hanging in the air.

Curiosity takes a selfie using the Mars Hand Lens Imager (MAHLI) located on the end of his robotic arm. The viewing angle of this camera is only 33 degrees and its main purpose is microscopic photography of Martian soil and rock. From a full arm’s length, this camera cannot completely capture the entire Curiosity rover, so in order to have the entire rover in the photo, you have to take several photos from different angles, and then glue them together.

In addition, the robotic arm is designed in such a way that when shooting, most of the arm is always out of the camera’s field of view. Those small parts of the robotic arm that do get into the frame are cut out when gluing, otherwise they would simply spoil the image by appearing in large numbers in random places in the picture.

On average, it takes about 70-75 photos to get one selfie. It takes a rover about 1 hour to make that many photos.