They will comb the waters and the floor of the Gulf of Mexico for clues.
They will visit areas where they found oil before and check out places it hasn't been detected.
It will be a busy 10 days for the 14 scientists aboard the R/V Weatherbird II, the research vessel from the University of South Florida that has been at the forefront of the investigation into the aftermath of the nation's largest environmental disaster.
The ship is scheduled to leave port at 6 p.m. on a mission to check areas that may have been impacted by the April 20 Deepwater Horizon oil rig explosion and sinking off the Louisiana coastline.
It will be the third such voyage for the Weatherbird.
The ship will visit the same areas where researchers in May found underwater plumes of degraded and invisible oil north-northeast of the BP well site, from which 172 million gallons of oil gushed. Scientists will also check out areas of the west Florida continental shelf where previously no signs of oil have been found.
David Hollander, chief scientist for the trip, said that researchers are anxious to see what the level of concentration the subsurface oil is at places where they found it back in May. They want to know if it has disappeared, thinned out or remained the same.
"If it stays there longer, that's bad news,'' Hollander said, stressing the importance of the fact-finding mission because USF is an independent body and not acting in the role of the government or a large corporation.
Officials will be looking for signs of oil, for evidence of dispersants, or the two paired together.
"This is a whole new game in deep-water blowouts,'' Hollander said. "We've never experienced this before.''
The trip, which costs about $250,000, is being paid for by the university's Office of Research and Innovation.
"It will be a very intense 10-day trip for the guys,'' said Bill Hogarth, dean of the College of Marine Science at USF in St. Petersburg.
Researchers will be taking water and sediment samples and also doing some work with fish and other marine life.
"We want to try to start that next phase and look at what impact it might have on the food chain and fisheries of the Gulf," Hogarth said.
That means, he said, scientists will be checking sources all along the food chain - the bacteria that eat the oil, the plankton that feed on the bacteria, the fish that feed on the plankton - to see what kind of impact the oil and the dispersants used to fight the spill might have.
The USF official said he was delighted that oil no longer was flowing from the ruptured rig a mile under the water's surface, and happy that federal officials maintain that much of the oil has disappeared.
"Just because you don't see it doesn't mean it's not having an impact,'' Hogarth said. "You expect surface oil to disappear. We're going to do what we do and report the science.''