Japan's newest island now has a name, Niijima, and it continues to grow.

The small volcanic island sits about 600 miles (970 kilometers) south of Tokyo, offshore of a small, uninhabited island called Nishino Shima. Located in Japanese waters, the newborn island is now one of about 30 known as the Bonin Islands, or the Ogasawara chain.

Niijima was first noticed on November 20. On the next day, the Japanese coast guard released video of the island forming, showing billowing smoke, steam, ash, and rocks exploding from a crater that had erupted from the sea.

At the time, Japanese scientists were unsure how long the island would last, as the ocean often reclaims such volcanic islets within a short time.

Since then, however, the island has grown significantly, thanks to ongoing eruptions of the underlying volcano, which sits along the Izu-Ogasawara-Mariana Trench. According to the Japan Meteorological Agency, Niijima has grown to 56,000 square meters (13.8 acres), about three times its initial size. It rises about 65 to 82 feet (20 to 25 meters) above sea level.

Japanese scientists now say that they expect the island has grown large enough to survive for at least several years, if not permanently.

According to NASA's Earth Observatory, Nishino Shima, which sits about 1,640 feet (500 meters) away from the new island Niijima, last erupted and expanded in 1973 and 1974. The two islands lie about 130 kilometers (80 miles) from the nearest inhabited island.

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While most people in Japan live on its four large islands, the nation is actually made up of thousands of islands.

In a NASA satellite image taken December 8, Niijima could be clearly seen next to the larger Nishino Shima. The water around Niijima was visibly discolored by volcanic minerals, gases, and seafloor sediment stirred up by the geologic activity. Faint white puffs of steam and volcanic gases were also visible in the image.

Volcanic activity has long reshaped the features of the planet, today particularly along the Rim of Fire, a fringe of coastline that surrounds much of the Pacific Ocean and that includes Japan.