Both Landsat 7 and Landsat 8 satellite orbit the Earth at an altitude of 705 kilometers (438 miles) in a 185-kilometer (115-mile) swath, moving from north to south over the sunlit side of the Earth in a sun synchronous orbit, following the World Reference System (WRS-2). Each satellite makes a complete orbit every 99 minutes, completes about 14 full orbits each day, and crosses every point on Earth once every 16 days.
The satellites’ orbits are offset to allow 8-day repeat coverage of any Landsat scene area on the globe. Between the two satellites, more than 1,000 scenes are added to the USGS archive each day.
The satellites traveling on the descending (daytime) node from north to south cross the equator at 10:00 a.m. +/- 15 minutes (Landsat 7) and 10:11 a.m. +/- 15 minutes (Landsat 8) mean local time on each pass to provide maximum illumination with minimum water vapor (haze and cloud build-up).
The Landsat 8 and Landsat 7 satellites each acquire data in accordance with their respective Long Term Acquisition Plan (LTAP). Each LTAP directs the acquisition of Landsat scenes, using parameters such as seasonality, land definition, historical cloud cover, gain settings, and sun angle.
Visit the Landsat Acquistions web page for acquisition schedules, calendars and additional information.