The Oort cloud is a vast cloud of cometary matter somewhere beyond Pluto (from that distance, the sun would look like a bright star) named after Dutch astronomer Jan Oort, who, along with Estonian astronomer Ernst Öpik, helped conceptualize a comet reservoir, existing beyond all of our current data gathering technologies.
This is Richard Preston writing in the October 26, 1987 issue of the New Yorker:
