Short answers, pulled from the story.
Martin Behaim is best known for producing the Erdapfel, the world's oldest known globe, in 1492. He oversaw its construction in Nuremberg, where it was financed by the city council. The globe is now held by the German National Museum in Nuremberg and is also called the Nuremberg Terrestrial Globe.
Martin Behaim was born in Nuremberg on the 6th of October 1459. He was the oldest son of Martin Behaim the elder and Agnes Schopper. His father was a merchant involved in long-distance European trade and was elected a senator of Nuremberg in 1461.
Behaim moved to Lisbon in 1484 and found favor at the court of King John II, serving as an adviser on navigation and astronomy. John II knighted him on the 18th of February 1485. Historians have found no evidence that Behaim made significant scientific contributions to Portuguese navigation, as the relevant methods and instruments were already in use.
No. Historian Johann Christoph Wagenseil made that claim in 1682, but no documentary evidence supports it. There is no record that Behaim ever sailed on a westward voyage of discovery, and neither Behaim nor Columbus ever referred to having met each other.
The Erdapfel contains more than 2,000 place names, 100 pictorial illustrations, 48 banners, 15 coats of arms, and more than 50 long legends. Its geography draws primarily from the second-century geographer Ptolemy, supplemented by Marco Polo, John Mandeville, and the Portuguese explorer Diogo Gomes. Many notations describe fabulous monsters, trade routes, and famous travelers.
Martin Behaim died on the 29th of July 1507 in the hospice of Saint Bartholomew in Lisbon, while visiting the city on business. He was 47 years old.