Date of discovery: February 2016
Location of discovery: Mars
Source NASA photo: http://mars.nasa.gov/mer/gallery/all/1/n/4269/1N507176992EFFCP40P1978L0M1.JPG
Found by: Streetcap1 of Youtube.
Reports of strange things in rover photos never seem to cease, but its always the public that reports them. Here Streetcap1 of Youtube caught an object not to far in the distance that is moving from right to left of the screen. The is a faded trail behind it...a distortion of sorts which tells us the direction it came from. It looks like the spacecraft in the distance is watching the Opportunity rover. Observing it.
Scott C. Waring