(Photo sent by Rick D.)

Lots of questions about why the R/V Thomas G. Thompson has been off west-facing West Seattle all day. It’s a 274-foot research vessel belonging to the Office of Naval Research and operated by the University of Washington; we’ve reported on it a few times before, including this note in 2010. We contacted the UW Oceanography department to ask about today’s mission; according to the reply from Su Tipple, it’s “on a 12-hour day cruise to video-document the most active methane seeps in the vent field off Alki Point, as well as taking methane and other water measurements.” We’ve reported on the methane research before, after another UW research vessel, R/V Rachel Carson, was seen in local waters, studying the bubbles as part of research that could eventually assist in earthquake prediction (detailed here in 2020; published in a study earlier this year, also summarized here). The plumes of methane bubbles are most prolific off Alki Point – rising more than 650 feet to the surface – and Kingston, according to researchers, but the methane’s source remains a mystery.