Simushir is one of the Kuril Islands — a Russian-controlled archipelago of more than 50 volcanic islands in the North Pacific Ocean.
Like the rest of the Kuril Islands, the sovereignty of Simushir has been passed back and forth between two nearby countries, Russia and Japan, several times over the last 400 years.
It was most recently used as a secret Soviet nuclear submarine base until 1994, but is now uninhabited.
The 5-mile-long (8 kilometer) landmass is home to four major volcanoes that can be seen from space.
A deep lagoon, known as Brouton Bay, can also be seen surrounding Uratman.
Simushir, a little-known Russian island and former Soviet naval base, is depicted in this striking satellite image. It features four end-to-end volcanoes that are surprisingly straight and evenly spaced. About 200 years ago, one of the biggest eruptions in recorded history occurred on one of the four peaks, drastically changing the Earth’s climate.
One of the more than fifty volcanic islands in the North Pacific Ocean that are under Russian control is the Kuril Islands, which includes Simushir. Over the past 400 years, Simushir’s sovereignty has alternated between two neighboring nations, Japan and Russia, multiple times, much like the other Kuril Islands. It is currently uninhabited, having most recently served as a covert Soviet nuclear submarine base until 1994.
Four prominent volcanoes that are visible from space are located on the 5-mile (8-kilometer) landmass. From southeast to northwest (left to right), these imposing buildings are Milna, Zavaritski, Prevo, and Uratman.
Milna last erupted in 1914 and is the tallest of the four, standing at 5,050 feet (1,540 meters). Zavaritzki, also called Zavaritskogo, is located next to it. It is approximately 2,047 feet (624 meters) above sea level and last blew its top in 1957, leaving behind a crater that is mostly hollowed out.
The most recent eruption of 4,460-foot (1,360-meter) Prevo occurred in 1825. There are no indications that Uratman, which is 2,224 feet (678 meters) high, has erupted in at least 12,000 years. On the outskirts of Uratman is a deep lagoon called Brouton Bay. The Soviet Union kept some of its nuclear submarines here.
Related: View the greatest space photos of Earth.
Goriaschaia Sopka, the island’s fifth smaller volcano, is situated on Milna’s northeastern flank, but satellite images cannot distinguish it from the larger volcanoes. Even though Goriaschaia Sopka and Milna are considered separate volcanoes, they are closely related.
According to NASA’s Earth Observatory, Simushir and the other Kuril Islands are hotspots for volcanic activity because they are situated within what experts refer to as the “Ring of Fire”—a 25,000-mile (40,000-kilometer) arc situated above tectonic plate boundaries encircling the Pacific Ocean’s outer edge. Two-thirds of the world’s terrestrial volcanoes are found in this region, which also experiences about 90% of all earthquakes.
The large one. .
There were reports of gloomy, bleak weather and the sun changing color in 1831, when the climate of the Northern Hemisphere cooled by an average of roughly 1 degree Fahrenheit (1 degree Celsius).
The volcano that caused this odd occurrence has remained a mystery, despite scientists knowing it was caused by a massive eruption.
However, in December 2024, a new study that matched ash deposits in polar ice cores to the volcano found that Zavaritzki was the culprit.
The researchers were surprised by this discovery because, probably as a result of Simushir’s remote location and the dearth of possible witnesses on nearby islands, there had been no previous indication of an eruption on the island in 1831.
