Naomi McKinnon knew something was up, but she wasn’t sure what. She went below deck for a minute and then rejoined her two crewmates on watch.
Then it hit her. Horizon to horizon, stern to bow, the sea shone around her as her 52-foot ketch passed south of the Indonesian island of Java on a moonless night.
“What the hell?” she remembered thinking.
What Ms McKinnon and her six crew members encountered in August 2019 was a surge of luminous seawater so bright and gargantuan that a satellite orbiting hundreds of kilometers overhead could see its glimmer. Last summer, a team of scientists reported the satellite performance that opened a window on one of the planet’s most puzzling features. The bioluminescent seas appear to be formed when trillions of tiny bacteria light up together.
Now, a researcher who authored this paper, Steven D. Miller, a satellite expert at Colorado State University, recorded how Ms. McKinnon and her crewmates used their own observations, cameras, and buckets of seawater to verify the satellite results — albeit unknowingly.
Late last year, after Ms. McKinnon was consulted by Dr. Miller’s research, she reluctantly volunteered. “I thought, ‘Maybe he doesn’t want to know,'” she recalls. “But his response was, ‘Wow! You’re the first person to confirm that!’ He was so excited. I was really glad I signed up.”
dr Miller reported Monday in the Proceedings of the National Academy of Sciences of the sailboat’s confirmation of the spacecraft’s observations.
There are two general types of bioluminescence at the sea surface. The usual one occurs when turbulent waves or other movements stimulate microorganisms to glow. Many nighttime beachgoers have seen the blue-green glow in breaking waves.
The other type – the species observed by the boat crew – is poorly known and appears to exist free of mechanical stimulation. Its rarity makes the joint observations from both the satellite and the ship an important hit for marine research.
dr Johan Lemmens, a retired doctor from Southend-on-Sea, England, was circumnavigating the world in the two-masted sailboat he owns and pilots when the sighting took place. He said he had never seen anything like it.
“Normal bioluminescence is when the waves light up or there’s a trail of light behind you,” said Dr. lemmens “You see that two or three times a year. That was different. The sea was lit, but the waves were black. That made it really scary. There was the idea that the light came from a deeper level.”
The crew lowered a bucket into the water and pulled out a sample containing several points of light that glowed steadily until the water was stirred; then suddenly the dots went dark. This reaction, according to the new paper, contradicts “normal” bioluminescence.
Ms McKinnon said she first noticed the glow around 9pm local time and that it intensified throughout the night and lasted until dawn. The satellite observations showed that the bright spot south of Java, Indonesia’s most populous island, persisted for at least 45 nights and grew larger than the combined areas of Vermont, New Hampshire, Massachusetts, Rhode Island and Connecticut.
Ms McKinnon studied biochemistry in college and was a research assistant in a laboratory at the University of Sydney in Australia before learning about circumnavigation at a sailing forum and joining the seafarers at the age of 24. In her laboratory, she studied deadly sea toxins, including those from box jellyfish, whose toxins not only attack the skin but also the heart and nervous system.
dr Lemmens, who grew up in the Netherlands, said the circumnavigation was a celebration of his retirement. His ketch Ganesha, named after a Hindu god of beginnings, carried a crew of seven.
Ms McKinnon said she did some internet research after her sighting off Java in port but didn’t learn much. She later joined the medical school at the Australian National University and was conducting another search last fall when Dr. Read Miller’s satellite paper.
“I still had that question in my head,” she recalls. “What was it?”
Steven HD Haddock, a bioluminescence expert at the Monterey Bay Aquarium Research Institute in California and co-author of the satellite paper with Dr. Miller said it was a wonderful coincidence that “reporting of the original science reached seafarers who reached out to us,” allowing the team independent confirmation of the rare phenomenon.
said dr Miller
Ms. McKinnon and crew’s observations offer glimpses of a great mystery – how tiny organisms can affect entire oceans.
“It’s a big coupled system,” said Dr. Miller on ocean currents and the atmosphere. “It’s important for us to understand how this fundamental level of the biosphere relates to this.”