Why do we always need to wait for ‘launch windows’ to get a rocket to space?

Earlier this week, the Artemis I Moon mission was dropped out again; and now the moon mission will have to wait for a new launch window. Just 40 minutes before the Space Launch System rocket was set to take off from Kennedy Space Centre in Florida on September 3, a leaking fuel line caused engineers to scrub the launch. So now the question arises what is a launch window, and why can’t a rocket go up at any time? And what does it mean to “scrub” it?

from IndiaTV World: Google News Feed https://ift.tt/0QbFAHX