Sorry, it's completely OT, but learning more about the Earth and the
   Space is always beautiful!  <3

   ======

   "Earth Observation from Space: the Optical View"

   Discover how optical Earth observation data is gathered and used in
   this free online course from the European Space Agency (ESA).

   Free Online Course – starts 12 Sep

   [1]https://www.futurelearn.com/courses/optical-earth-observation

   sea sea
   --
   "I disapprove of what you say, but I will defend to the death your
   right to say it."

References

   1. https://www.futurelearn.com/courses/optical-earth-observation