I cannot get a consistent Sol to date conversion routine running. Sols up to about 40 seem to convert correctly but after that it seems to go completely wrong. Does anyone have any way to convert Sols like 284 or 1000 for example to a reliable date(s)? I realise that Sols are relative to the spacecraft landing date, so any conversion routine would have to take that into account.
I have got examples from texts and I do not know how they are worked out.
This for example from Wikipedia..... "Spirit, mission designation MER-A (Mars Exploration Rover - A), is the first of the two rovers of NASA's ongoing Mars Exploration Rover Mission. It landed successfully on Mars on 04:35 Ground UTC on January 4, 2004, three weeks before its twin Opportunity (MER-B) landed on the other side of the planet."
and this "On May 1, 2009 (5 years, 3 months, 27 Earth days after landing; 21.6 times the planned mission duration), Spirit became stuck in soft soil."
"On January 21, 2004 (Sol 18)," .... is based on Sol 0 being the landing day.
"The images were acquired on Spirit's sols 583 to 586 (Aug. 24 to 27, 2005),"