The MER team hasn't officially stated what they believe the vein may be composed of but they definitely sound intrigued.
"These are different than anything from anything we've ever seen with either rover, a completely new thing on Mars, never seen anywhere," Squyres said. "And we're pretty charged up about it."
In the meantime the rest of us will have to wait for further information.
Opportunity is now facing its fifth Martian winter and the MER team must soon plan driving maneuvers to place it at a prime location to weather the long months of frigid temperatures and reduced sunlight. Most importantly it will need to find a north-facing slope that will position it at a ten- to fifteen-degree angle, to take best advantage of the available sunlight on its already dusty solar panels. While this potential discovery is undoubtedly exciting, Opportunity's ultimate survival must take precedence.
Once the six-month-long Martian winter is over, Opportunity can resume exploration of the area around Cape York, an area that has already proven itself to hold promises of many never-before-seen features.
"All the rocks we're seeing here are completely different than Opportunity has ever seen and different significantly than the rocks Spirit saw as well," said Bruce Banerdt, MER project scientist at JPL. "So we're already picking up new geology and new rocks and new petrology that no one's ever encountered yet on the Martian surface. It's all great stuff. There is a lot of activity going on and the science team is really jazzed right now."
Find out more in the Mars Exploration Rover 2011 Update on The Planetary Society blog, and keep up with Opportunity's progress on Stu Atkinson's blog The Road to Endeavour.
Image credits: NASA/JPL-Caltech. Edited by Stu Atkinson.