A standard hour (also known simply as an hour or as a Standard Time Unit) was a temporal measurement unit used in many parts of the galaxy. An hour was equal to sixty minutes. On Coruscant, there were 24 hours in a day and 368 days per year. Immediately after the destruction of Alderaan, Han Solo—unaware of the devastation of the planet—calculated the estimated time of arrival of the Millennium Falcon's trip to Alderaan in terms of hours, reckoning that the ETA was about 0200 hours from the position of the Falcon at the time.