This was a feast and a treat for my inner science nerd. Scientists from earth have sent an enormously expensive probe to gather unique data from near the pole of a tremendously high gravity planet. They have high hopes that this data will help them solve a number of thorny scientific problems and provide the next great leap forward in technological advancement. Unfortunately, the probe has malfunctioned, and although they know it completed the data gather, and can see that its there, and intact, its not coming back. No one can go repair it or collect the data from it because humans can only survive at the equator of this planet. When they travel into the higher latitudes the gravity is too much for them and anyone who tried to travel to the pole would implode before he got there.
Fortunately, the higher latitudes are inhabited. By intelligent foot and a half long lobster/caterpiller creatures who are adapted to the high gravity and perfectly capable of retrieving the probe. If they can be persuaded to travel the thousands of miles over unknown territory through hurricanes and floods and encounter previously undiscovered beasts and civilizations. Luckily the Earthers manage to find a flotilla of traders with a strong sense of adventure who are willing to take on the mad task.
The rest of the book is the joint exploration and trade mission of the lobster creatures, with much advice and kibbitzing from the scientist liason assigned to work with them via radio. A lot of very geeky fun can be had reading the attempts of the two species to understand one another and strategize as the creatures travel along the route to the probe. I found the creatures to be charming, and the ways both parties had to work through mutual incomprehension due to the very different physical laws of their two worlds was often very funny in a geeky sort of a way. I also loved the goodwill with which these very different creatures tried to work together and understand each other.
This is a very specific kind of book however. If you are not a person who likes trying to understand how a radio works, or why light bends or how having methane seas would affect buoyancy, this may not be for you. For me, it was great fun.