During the last few days of 2014, a violent plume of smoke rose up over 9 kilometers (30,000 feet) into the skies above the South Pacific. In the following weeks, satellites noticed that the underwater volcanic eruption had actually spawned a new island in between two older islands in the Kingdom of Tonga. The island has been nicknamed by locals Hunga Tonga-Hunga Ha'apai.
Recently scientists from Sea Education Association and NASA stepped foot on the baby island and were happy to see the black volcanic land mass is already home to a thriving ecosystem, complete with pink flowering vegetation, nesting sooty tern birds, and barn owls.
“We were all like giddy school children,” Dr Dan Slayback, a researcher at NASA, told the NASA Earth Expedition blog about arriving on the island.
While the island’s biological curiosities are certainly an attraction, the team primarily made the visit for the geology. Most new islands born from volcanic eruptions only last a few months before falling back into the sea, so researchers initially expected the same for Hunga Tonga. However, they’re now pretty certain the island is here to stay, making it one of only three new islands in the last 150 years that have survived longer than a few months.
Dan and his team collected a number of rock samples for mineral analysis to get a better understanding of its geology and how it might be affected by future erosion from the bold Pacific waves. It's also hoped this unusual otherworldly place could provide an unprecedented look at how geological forces begin to shape new land masses, perhaps even providing clues about the geological history of Mars.
“Most of it is this black gravel, I won’t call it sand – pea-sized gravel – and we’re mostly wearing sandals so it’s pretty painful because it gets under your foot," he said. "[But] Immediately I kind of noticed it wasn’t quite as flat as it seems from the satellite.”
Ever since its birth, satellite imaging has been used to track the size and ever-shifting shape of the island, however, nothing beats being there for real. Their on-the-ground presence revealed the extent of the island's erosion, deep gullies have already been carved out by rainfall.
“It really surprised me how valuable it was to be there in person for some of this. It just really makes it obvious to you what is going on with the landscape,” Dan said.
“The island is eroding by rainfall much more quickly than I’d imagined. We were focused on the erosion on the south coast where the waves are crashing down – which is going on. It’s just that the whole island is going down, too."
The data collected on this brief visit will be used to more accurately create a 3D rendering of the island, to try and understand what processes are allowing it to remain above the waves, unlike so many others.
Hunga Tonga-Hunga Ha’apai captured in time-lapse photography from space for the first time, between Jan 2015 and Sept 2017, with added three dimensions to reveal how the landscape has responded to the forces of the Pacific. NASA Scientific Visualization Studio