Kelly McSweeney

Aug 16th 2019

Volcanic Landforms Reveal Clues About Planetary Origins


The South Pacific is home to new islands that seemingly appear out of nothing. Volcanoes erupt below the ocean’s surface, spewing hot lava that eventually cools down and hardens, becoming an island.

As volcanic activity creates new land formations across the globe, scientists study these brand-new islands to learn how our planet was formed, as well as other planets and moons in the solar system.

Land Appearing Out of Nowhere

Most of the South Pacific’s volcanic landforms wash away in a couple months, but a new island that formed in 2015 in the island nation of Tonga is lasting long enough for scientists to investigate.

According to, the island, unofficially called Hunga Tonga-Hunga Ha’apai, formed when an undersea volcano erupted in December 2014 through January 2015. Scientists kept an eye on the island before it even formed and used satellite imagery to watch it slowly rise out of the ocean.

The newborn island comprises dramatic cliffs, a crater lake and new plant life. The land provides a peek into our planet’s past, demonstrating in real time what it’s like when new land develops. NASA scientists suggest that the island could be our best replica of ancient Mars.

Jim Garvin, chief scientist at the Goddard Space Flight Center explained, “We have an eruption on Earth with an accelerated erosion because it’s in a marine environment, but on Mars, that environment may have been very ephemeral. By looking at these things in more detail, we can start to put time constraints on … the persistence of water, [which] is a holy grail on Mars.”

According to the National Park Service (NPS), the Hawaiʻi Volcanoes National Park displays the results of at least 70 million years of volcanism, migration and evolution, and active volcanoes are still adding to the island of Hawaiʻi. These changes can cause drama on Earth, where we’re used to divvying up land. When volcanic eruptions create new land, who owns it? Vice reports Hawai’i is continuously expanding, with lava flows not only covering existing land but also spilling into the ocean creating new masses called lava extensions. This ever-changing landscape has caused disputes over ownership, but new land belongs to the state.

How Scientists Study Volcanic Landforms

Iceland’s volcanoes hold hints about the chemical reactions that occur when lava interacts with ice, as scientists suspect it does on Jupiter’s moon Europa. In an attempt to determine how planets and moons evolved, planetary scientists from NASA’s Goddard Space Flight Center are studying the lava fields of Iceland’s glacier-covered volcanoes, according to

They’re measuring temperatures, drilling through ice and using a technique called Raman spectroscopy to analyze the chemistry of the ice. The information they gather will help them understand Earth and beyond.

There are volcanoes throughout the solar system. For example, the moon’s dark patches indicate inactive volcanoes, and there are remnants of volcanoes on Mercury, Venus and Mars.

“You can use Earth science to study volcanoes on this planet and then apply that knowledge to the Moon, Mars and other bodies,” Patrick L. Whelley, a Goddard planetary geologist told “Plus, we don’t have the luxury of watching volcanic eruptions up close anywhere besides Earth.”

Iceland is a good substitute for Mars because they are both covered in a volcanic rock called basalt. According to, Iceland grew from continual volcanic eruptions in the last 15 to 20 million years.

Geological Discoveries Beyond Earth

Today’s geological discoveries hint at our solar system’s geological past. By figuring out the best techniques for analyzing volcanic landforms in the South Pacific islands and Iceland, scientists are also helping to develop methods that could be deployed on future space missions to dig into the origins of planets and moons throughout our solar system.