Quotes from Lars Lindberg Christensen

Time on Hubble is a precious commodity. Astronomers across the world regularly ask for much more time than is available. Keeping Hubble working 24/7 is no small task. Not a single second must be lost and all tasks — either observations or so-called 'housekeeping' tasks, such as repositioning of the telescope, or uploading new observing schedules — are meticulously planned.