Ghost or Angel on Mars!
Top photo: the first picture and magnification. I circled in red the location of the "Thing" white.
Click on link below to enlarge top photo - http://www.ufodigest.com/sites/default/files/field/image/Opportunity-SOL-123-1-LARGE-jpg.jpg#overlay-context=article/ghost-or-angel-mars
Above, the second picture and magnification. The "Thing" is slightly turned white, and high environmental slightly higher.
Above, the "Thing" is still turned white, and has taken a lower position.
Many more photos and anomalies at Christian's website: http://ovniparanormal.over-blog.com/