When people talk about arriving at such locations in such tiny timescales, people often don't realize that you need to slow down otherwise you'll just zip right past your destination. If your estimation is correct then, it'll take twice that to arrive there. As too much deceleration will turn everyone into a goop of flesh on the windshield of the spacecraft. If you have any questions about the possibilities of space travel or any hypothetical situations (what if the deathstar replaced the moon etc) I may make a post on it of what would happen with mathematics included on a separate PDF.