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According to one of the answers to a question concerning Opportunity, the rover has a top speed of 180 meters per hour (no reference).
Based on daily performances however a reasonable speed estimate is 100 meters a day.

According to this article, the rover needs about 100 watts to drive, but it doesn't mention the speed that is reached with that 100 watts.

Are there any references about the driving power of the rovers motors ?

The solar power supplies varies between 300 to 900 watt-hours per day.

The crash site of the Schiaparelli lander is about 54 km away from where Opportunity was at the time, so should it not be possible to reach that site within a year, or are there other factors to take into account ?

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No, certainly not within a year. Maybe, if its incredible luck holds out, in 17 years. Opportunity would need longer than it has already been there to make such a journey, based on the traverse to date.

Schiaperelli impacted at 6.21° West longitude (353.79° East longitude -- there are unfortunately two Mars longitude conventions), and 2.07° South. Opportunity is currently at about 5.35°W and 2.34°S. So today they are about 53.4 km from each other.

Opportunity's total traverse to date over the last 14 years and three months has been 45 km. So it would take about 17 years to get there. If it could go in exactly a straight line there, which it surely cannot. Opportunity could not sustain 100 meters per sol every sol, due to energy, seasons, terrain, and operations down time. Not to mention a bum steering motor. If I crank up my optimism to extra large, I could imagine a pedal to the metal sustained rate of 20 meters per sol, and a traverse inefficiency of 30%. Then it would take about ten years.

I feel compelled to point out that Opportunity was designed and qualified for a three-month lifetime, and a grand total of one kilometer of traverse. It is way, way, way beyond the warranty.

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  • $\begingroup$ Yes, that's worth mentioning ! But over the last 14 years a lot of time went in staying somewhere to examine. In april 2017 it still drove 132 m. in a single sol and tank steering is used whereever possible. $\endgroup$
    – Cornelis
    Apr 21, 2018 at 17:46
  • $\begingroup$ I included the assumption of no science investigations in my optimistic estimate of 20 meters per sol. It also spent a lot of the last 14 years trying to get from point A to point B. When just trying to go as far as possible, with all the energy you need and if your drivers didn't go home for the weekend, an average traverse is 30 meters. $\endgroup$
    – Mark Adler
    Apr 21, 2018 at 17:48
  • $\begingroup$ Are you willing to go to 40 meters, regarding the Meridiana plain is much easier to traverse than the rim of Endeavour ? :) $\endgroup$
    – Cornelis
    Apr 21, 2018 at 18:01
  • $\begingroup$ Nope. 30 meters was a good day. There were 100 meter days, but they were the exception. $\endgroup$
    – Mark Adler
    Apr 21, 2018 at 22:18
  • $\begingroup$ Aren't they keeping it in the crater to keep its solar panels pointed optimally as well? $\endgroup$
    – GdD
    Apr 22, 2018 at 8:20

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