Mosaicking the earth every day

Feb. 22, 2017 from 3:30 to 4:20 p.m. — Physics/Astronomy Auditorium, room A102

Kelsey Jordahl

Leads Mosaics team at Planet Labs

Watch a recording of this seminar on YouTube.


Planet Labs currently operates about 60 Earth observation satellites imaging 50 million square kilometers of land area per day. We plan on tripling those figures in coming months, fulfilling our Mission 1 to image the surface of the Earth every day. Global mosaics are created from these images at regular intervals (quarterly, monthly, and weekly) by selecting the best quality scenes (e.g. cloud- and haze-free), color balancing, and seamlessly compositing millions of scenes to create continuous maps of the Earth for each time slice. As our data rate increases, we plan on scaling up the cadence of our mosaics, including a building a continuously updated “dynamic” mosaic of the most recent cloud-free images of the Earth. Daily data at 5 meter spatial resolution will open up new analysis techniques previously limited by the temporal or spatial resolution of existing instruments.


Kelsey Jordahl leads the Mosaics team at Planet Labs. He previously worked as a Scientific Software Developer at Enthought, working with clients in finance, energy, government and academia and teaching python to scientists and engineers. Prior to that he taught physics at Marymount Manhattan College and did research in marine geophysics. He holds a Ph.D. from the MIT-Woods Hole Oceanographic Institution Joint Program in Oceanography and a B.S. in Physics from Eckerd College. He lives in Spokane, Washington.