Earth remote sensing (ERS) is earth surface condition data reception by use of distance sensors having no contact with Earth surface. These sensors can be installed on spacecrafts, airplanes and other vehicles.

ERS methods can include passive, utilizing objects' reflected natural and secondary thermal radiation caused by solar radiation, and active, utilizing objects' radiation inducted by directed artificial source. Measured electromagnetic waves range from a fraction of a micrometer (visible light) to meters (radio frequencies). Objects identification and classification possibility is based on objects of different kinds – rock formations, soil, water, vegetation – reflecting and absorbing various wavebands of electromagnetic radiation differently.

ERS spacecrafts are used to examine natural resources and solving meteorological problems. They primarily carry optical and radiolocation equipment. The latter provides an advantage of being able to monitor Earth surface during any time of the day and without regard to atmospheric conditions.

Russian Space Systems is the Russian ERS systems operator and Federal ERS data repository operator:

• Space imagery and data reception from Russian ERS spacecrafts;
• Space imagery processing and cartographic production.