Final answer:
The Magellan and Columbus expeditions aimed to establish a direct route to Asia for trade, compelled by competition and the desire to spread Christianity. While Columbus unintentionally discovered the New World, Magellan's voyage confirmed the existence of a massive separate landmass and the immensity of the Pacific Ocean.
Step-by-step explanation:
The objective of the Magellan and Columbus expeditions was primarily to seek a direct trade route to Asia. These explorations were driven by the need for new trading routes after the fall of Constantinople to the Ottoman Empire in 1453, which put the lucrative spice trade under the control of Muslim powers. The Spanish monarchs, Isabella and Ferdinand, were motivated to finance these voyages not only to compete with Portugal, but also to expand Catholicism and gain a commercial advantage. Columbus set sail with hopes of charting a westward route to India to establish trade and spread Christianity, while Magellan was commissioned to find an oceanic passage. They both aimed to circumnavigate the globe to reach Asia, which had become a pressing objective for European monarchs looking for new wealth.
However, while seeking a direct route to Asia for trade, Columbus stumbled upon the New World, radically changing the course of history. This unintentional discovery led to the colonization of the Americas. Magellan's voyage also demonstrated the vastness of the Pacific Ocean, proving that Columbus's calculations were incorrect and establishing that there was indeed a massive landmass separate from Asia.