As BP's oil gushed into the Gulf of Mexico week after week last summer, we got accustomed to wildly different estimates for how quickly the oil was leaking and how much entered the gulf. Now, 10 months after the mess began, government and independent scientists have wildly different estimates for how much of the oil remains. Oceanographer Samantha Joye, speaking at the American Association for the Advancement of Science annual conference in Washington this weekend, revealed the findings of her trips to the Gulf to study the seafloor. In December she dove to areas around the site of BP's well blowout, finding—and photographing—layers of gunky hydrocarbons. The oil was up to inches thick in places.