CAN ANYONE BECOME A GEO-PROFILER?

Sentinel-1a alone sends 8,000 gigabits of data back to Earth every day. What makes the satellite unique: In theory it allows anyone to play the role of environmental researcher or search the seas for unusual objects from the comfort of one’s home. That’s because: “The data are completely free to access and can be downloaded from the Internet,” says Sentinel developer Michael Rast (http:// scihub.esa.int). Sentinel can even help expose illicit fishing vessels and polluters, as Volker Liebig, the ESA director of Earth Observation, reveals: “Using radar, the satellite can see very clearly when a ship emits oil residues into the sea or when an oil spill has taken place.” Sentinel’s predecessor, Envisat, had also been used in the hunt for ocean polluters. The advantage Sentinel has over Google Earth: It records every point on the planet every five days, “in contrast with Google, where the data can be up to two years old,” says Liebig.