Why Don’t We See the Curiosity Rover’s Arm When it Takes a Selfie?

This self-portrait of NASA’s Curiosity Mars rover shows the vehicle at the “Big Sky” site, where its drill collected the mission’s fifth taste of Mount Sharp, at lower left corner. The scene combines images taken by the Mars Hand Lens Imager (MAHLI) camera on Sol 1126 (Oct. 6, 2015). Credit: NASA/JPL-Caltech/MSSS

Every time the Curiosity rover takes a ‘selfie’ on Mars, we get the same questions: “How was this picture taken?” “Why isn’t the rover’s arm or the camera visible in this picture?” “In all of Curiosity’s selfies, the camera mast is never visible… why?” And (sigh) “What is NASA hiding???”

The answer is simple and quite logical. Look any selfie image you’ve taken. Does your hand show up in the picture?

No, because it is behind the camera.

The same is true with the rover’s arm. It is behind the camera, so it isn’t part of the picture. In your own selfies, if you’ve done a good job of positioning things, your arm doesn’t appear in the photo either. For exmaple, take a look at this selfie taken last night by Astronomy Cast co-host Pamela Gay of her co-host (and Universe Today publisher) Fraser Cain, along with their fellow speakers at the Next Frontiers Symposium at Ohio State University.

OSU pre-talk selfie w @fcain @PaulMattSutter, Ty Owen, & astronaut Ron Sega pic.twitter.com/tUCM74ptOm

— Pamela L. Gay (@starstryder) October 14, 2015

Just think of the rover’s arm as the ultimate interplanetary selfie stick. The best selfies are where the stick doesn’t show up in the image and it appears you had your own photographer. That’s what happens with the Curiosity rover self-portraits.

Additionally, while the rover selfies look like they are just one single image taken by the wide-angle camera on the rover, it is —> Read More