No expert, but I'm thinking if you 'know bugger all about photography' you'd be far better off sticking with your phone rather than fannying about with multiple camera settings you have no hope of mastering between now and then, thereby missing much of the experience of seeing that thing you've come all that way to see. Phone upgrade to one with a high spec camera would seem to me to be a far better option.
I'd go a bridge camera, my favourite would be the Canon SX70. Does not fit the pocket though. https://www.google.com/search?q=bes...IHcJMBW0Q9QEwAHoECAcQAw#imgrc=rHN8EoO8J1t1hM: