Island sprang up near Tonga three years ago, giving researchers a glimpse of how flora and fauna colonise it.
Nasa scientists have landed for the first time on one of the world’s newest islands and discovered the three-year-old land mass is now covered in a sticky, mysterious mud, as well as vegetation and bird life.
The volcanic island sprang up in the ocean surrounding Tonga three years ago, one of only three new islands to emerge in the last 150 years that have survived more than a few months.
Dan Slayback of Nasa’s Goddard Space Flight Center was desperate to visit the remote location, because scientists still have scant knowledge about how and why new islands form. A team from Nasa visited in October – after previously studying the island using only satellite imagery – and Slayback detailed their findings in a Nasa blog post.
The island erupted from the rim of an underwater caldera in early 2015, and remains unnamed, but is sometimes referred to as Hunga Tonga-Hunga Ha‘apai – the names of its neighbouring, established islands.
Slayback and his team landed on what had looked like a black-sand beach on satellite but was actually made up of pea-sized gravel that made walking painful.
Vegetation was discovered beginning to take root – with the seeds likely deposited by birds flying overhead – and a barn owl has begun to make its home on the young island, as well as hundreds of nesting sooty terns.
A light-coloured, sticky, clay-like mud continues to “baffle” Slayback and his team, as to exactly what it is, what it is made of and where it is coming from.
“In the satellite images, you see this light-coloured material,” he said. “It’s mud, this light-coloured clay mud. It’s very sticky. So even though we’d seen it we didn’t really know what it was, and I’m still a little baffled of where it’s coming from. Because it’s not ash.”
Rock samples were collected for mineral analysis, and a high-precision GPS unit and aerial drone was deployed to estimate the island’s elevation and more closely survey the uninhabited new land.
“It really surprised me how valuable it was to be there in person for some of this,” Slayback said.
“It just really makes it obvious to you what is going on with the landscape,”
A high-resolution 3D map will now be made of the island, and Slayback and his team aim to return next year for further study.
Initial estimates suggest the island may survive up to 30 years, before succumbing to the pressures of the ocean.