What is the letter writer intending to do/beginning to do? Is this a noble undertaking?

The letter writer, Captain Walton, is intending to sail to the North Pole, a "country of eternal light," in order to find "a passage near the pole to those countries, to reach which at present so many months are requisite"; in other words, he is hoping to find the Northwest Passage.  Such a passage would provide a shipping route that bypasses North America and connects the Atlantic and Pacific oceans.  Captain Walton is also interested in "ascertaining the secret of the magnet, which, if at all possible, can only be effected by an undertaking such as [his]."  
The captain has a great desire for adventure and glory.  He even says to his sister, Mrs. Saville, the intended recipient of his letters, "And now, dear Margaret, do I not deserve to accomplish some great purpose.  My life might have passed in ease and luxury; but I preferred glory to every enticement that wealth placed in my path."  Thus, I think this undertaking can be described as noble.  On one hand, Captain Walton has a clear desire to improve life for humanity, finding a new shipping route would greatly benefit his country: this seems noble.  On the other hand, he wishes to accomplish these things not only to assist humanity but also to bring himself personal glory: this seems less noble than a pure desire to help one's fellow human beings.