Por que o Rebel Blockade Runner estava tão perto de Tatooine?

Esta não é uma coincidência de todo.

A Princesa Leia estava viajando para Tatooine para encontrar Obi-Wan Kenobi e pedir a ele que ajudasse a Aliança Rebelde. Quando sua nave é interceptada, ela tem que improvisar, então ela envia R2-D2 para a superfície do planeta com uma mensagem para Obi-Wan:

General Kenobi. Years ago, you served my father in the Clone Wars. Now he begs you to help him in his struggle against the Empire. I regret that I am unable to present my father's request to you in person, but my ship has fallen under attack and I'm afraid my mission to bring you to Alderaan has failed.

Isto é endereçado diretamente na nova novela de Star Wars (canon). Simplificando, a missão de Leia tinha duas partes. Em primeiro lugar, para coletar os planos para a Estrela da Morte e, em segundo lugar, para coletar Obi-Wan Kenobi de seu esconderijo em Tatooine.

Admitting she failed made the words taste bitter in her mouth. Though she and the crew of the Tantive IV had downloaded the information and made the jump to Tatooine, she wouldn’t be able to complete the second part of the mission. Her father had requested that she seek out an old friend, one General Kenobi, because, in his own words, “a war demanded warriors” to fight. A legendary Jedi Knight, Kenobi had gone into secret exile on the remote desert planet to avoid the deadly purge that had wiped out his order.

_{^{A New Hope: The Princess, the Scoundrel, and the Farm Boy}}

Isso obviamente explicaria sua proximidade com o planeta.