Despite the common public perception of the patch existing as giant islands of floating garbage, its low density (4 particles per cubic metre (3.1/cu yd)) prevents detection by satellite imagery, or even by casual boaters or divers in the area. This is because the patch is a widely dispersed area consisting primarily of suspended “fingernail-sized or smaller”—often microscopic—particles in the upper water column known as microplastics.[4] Researchers from The Ocean Cleanup project claimed that the patch covers 1.6 million square kilometres (620,000 square miles)[5] consisting of 45,000–129,000 metric tons (50,000–142,000 short tons) of plastic as of 2018.
NOAA stated:
While “Great Pacific Garbage Patch” is a term often used by the media, it does not paint an accurate picture of the marine debris problem in the North Pacific Ocean. The name “Pacific Garbage Patch” has led many to believe that this area is a large and continuous patch of easily visible marine debris items such as bottles and other litter – akin to a literal island of trash that should be visible with satellite or aerial photographs. This is not the case.