The story of Opportunity, the Mars rover was all over the online world last week and in particular its poetic last words: 'my battery is low and its getting dark.' So its a bit of a disappointment to discover that this didn't actually happen! The quote was a (well intentioned) attempt by a journalist to distil what NASA engineers had told him down to its essence.
No Matter. The story still made us all aware of the exploration of Mars for a few days and in that time many of us will have learned more than we knew before about that planet and how difficult interplanetary explorations are always going to be.
We learned how difficult predictions can be when you're dealing literally with an alien environment. The rover was meant to last 3 months, after which it was assumed that dust would have covered its solar panels. There was also a risk that it could become stuck on the rocky and sandy landscape before that. In the end it was the twin perils of landscape and dust that did for both, so NASA wasn't far wrong. Spirit became stuck on the surface in 2009 but it wasn't until 2018 that Opportunity was caught in a huge dust-storm from which it couldn't seemingly recover.
We also learned about what the rovers discovered. Immediately after landing, opportunity spotted a rock just a few metres away. Analysis quickly revealed that the rock could only have ended up there if carried by water, and therefore established that not only was there once water on Mars but that it flowed in some quantity.
So its a pity that the poetic story of the final transmission isn't true. But there is still poetry in the ending: Opportunity, after 15 years and having travelled an off-earth record 45 km, came to rest in Perseverance Valley, and NASA signed off by playing Billie Holiday singing:
I'll find you in the morning sun And when the night is new I'll be looking at the moon But I'll be seeing you
And, as another example of how physics and poetry are not mutually exclusive.....
