After six years of struggling around over Mars' surface, Spirit probably has succumbed in the cold Martian winter and went without getting enough power in its solar panels.
originally Spirit and its twin Opportunity were deemed to work for three months and whatever would come next was a nice little extra. That nice little extra started about six whole years ago.
While "Oppy" happily trotted along on Mars from crater to crater, Spirit had a troublesome odyssey. A constant shortage of power due to dusty solar panels and just not enough sunlight to absorb, Spirit became cripple. First the right, and then the left front wheel too, were ground to a halt by sand and dirt it became a stationary research platform. Unfortunately, Spirit needed more power to survive the winter and went in to hibernation. No response has been heard since then.
Now the brave little rover is given up on.
One of the coming projects will be a rendition of Spirit, as it is now, at its "base", called Troy.
Now I am not an animist kind of person but this little comic grabs me by the throat every time.
Farewell, Spirit. You did a very good job.
Soon I'll try and make a diorama of it.