Constellation
With only a single polar orbiting satellite, exactEarth can provide complete global coverage. As the satellite orbits north-south, the Earth turns east-west underneath the orbital plane. Within about 12 hours, the satellite will have observed every point on the planet. During that 12 hour period, the poles will have each been observed every 100 minutes.
Ideal Orbits
The exactEarth constellation is currently being deployed. Over time we anticipate launching many satellites, first to achieve and then to maintain a global revisit time of less than 90 minutes. In 2010, the exactEarth constellation includes three satellites with two more being readied for launch. With the launch of the fourth satellite, the constellation provides average revisit times better than 90 minutes for most of the Earth - at latitudes higher than about 40 degrees. This corresponds to over 10 observations per day anywhere on the planet - and even more at higher latitudes.