Nishinoshima
© JAPAN COAST GUARD
Image of Nishinoshima taken by the Japan Coast Guard on June 29.
A volcanic island in the Pacific Ocean appears to be experiencing a "vigorous growth spurt," with images from space showing it expanding in size since the middle of June.

The island, Nishinoshima, is located about 600 miles south of Tokyo, Japan. While it first emerged from the sea in the 1970s, it started growing in 2013 following an eruption of an underwater volcano. Initially, another volcanic island was formed around 1,600 feet from Nishinoshima, but in 2014 satellite images showed the two had joined together to form one landmass.

Scientists thought the second island would disintegrate with time. However, the island continued to grow and in the last month, more volcanic eruptions have led it to increase in size even further.

Images from a NASA satellite taken on July 4 showed heat signatures from erupting lava. Aerial photographs from Japan's Coast Guard also show how volcanic activity appears to have started up in May, with more ash and lava being produced than had been over previous months.


According to Japan's NHK news agency, researchers from the Geospatial Information Authority of Japan say the southern part of the island has expanded by almost 500 feet between June 19 and July 3.

A statement from the Japan Coast Guard said an observation of the volcano on June 15 showed activity had increased. It said continuous eruptions were taking place at the central crater, with lava flowing into the sea and discolored brown water seen on the east coast of the island.

In a statement, Nogami Kenji, from the Tokyo Institute of Technology, said the elevation of the lava appears to be high, with the magma close to the summit of the central crater. He said as long as the supply of magma continues, so will the eruption.

NASA Earth Observatory said the island has been "going through a vigorous growth spurt" since the middle of June, with satellite images showing eruptive activity at Nishinoshima.

It said that on July 3, the volcanic plume from the island rose up to 15,400 feet into the air, with ash rising to over 27,000 feet the following day. This is the highest a plume has risen since 2013.

The Smithsonian Institution's Global Volcanism Program said explosions from the volcano sent lava to the south west. It said photographs taken during a flight over the volcano suggested a possible collapse of the southwest part of the main crater.

Nishinoshima is now over one square mile and, as of January, 2018, stands at over 500 feet in height.