This wide-angle image of Vostok Station illustrates the layout of the research facility, where Russian, French, and American scientists collaborate on studying the lake and investigating the potential for deep ice coring in Antarctica. Photo courtesy of NOAA/Getty ImagesKey Insights
- Lake Vostok, concealed beneath 2 miles (3.2 km) of Antarctic ice, is the largest of Antarctica's 379 subglacial lakes, roughly equivalent in size to Lake Ontario.
- It was discovered using radio-echo sounding and has captured the attention of scientists, who speculate it might harbor microbial life, even though it has been isolated under ice for 15 to 20 million years.
- Exploring the lake could shed light on the potential for life beyond Earth, as its conditions resemble those found on moons such as Europa (Jupiter's moon) and Enceladus (Saturn's moon).
Around 53 million years ago, Antarctica was a thriving, forested landscape, a rich environment where palm trees flourished. Today, however, over 97 percent of this southernmost continent is covered by thick ice.
The impressive ice sheet that envelops Antarctica holds an astonishing 6.4 million cubic miles (27 million cubic kilometers) of frozen water. In some regions, the ice extends more than 2.2 miles ( kilometers) deep.
If all the ice were to melt, the global sea level would rise by 190 feet (58 meters). As it stands, this frozen expanse hides an entire world beneath its icy surface.
Over 379 "subglacial lakes" are trapped between the Antarctic bedrock and the ice sheet. Despite being surrounded by miles (or kilometers) of ice, these lakes remain liquid. Researchers have found that many of them are also interconnected.
Lake Vostok is the largest of these subglacial lakes. About the size of Lake Ontario in North America, this hidden gem has piqued both interest and controversy for many years.
The Legacy of Exploration
On January 27, 1820, Fabian Gottlieb von Bellingshausen — a captain in the Russian Imperial Navy at the time — became the first to officially spot the Antarctic continent. He was commanding an expedition with the flagship named "Vostok," which means "east" in Russian.
The USSR later honored his achievement. About 800 miles (1,300 kilometers) from the South Pole, the Soviets established a research station in 1957. In tribute to Bellingshausen's discovery, it was called Vostok Station.
The name was a fitting choice. The Antarctic Ice Sheet is divided into three main sections: the West Antarctic Ice Sheet, the Antarctic Peninsula Ice Sheet, and the East Antarctic Ice Sheet.
Vostok Station is located on the eastern section of the ice sheet. Since "Vostok" translates to "east," the name is perfectly aligned with its position.
While analyzing seismic data collected in the 1950s, Russian geographer Andrey Kapitsa began to suspect that a massive liquid lake might be hidden beneath the East Antarctic Ice Sheet, near Vostok Station.
It took quite some time to find solid evidence.
Locating Lake Vostok
Scientists utilize penetrating radar to assess the thickness of ice sheets. First, high-energy radio waves are transmitted through glaciers, ice sheets, or ice caps. If echoes are reflected back, they can provide key insights into the structure of the ice below.
In the 1960s and 1970s, this technology began identifying subglacial lakes throughout Antarctica. It turned out that Kapitsa's theory was absolutely correct.
A radio-echo survey, combined with satellite measurements, ultimately confirmed the existence of a massive lake hidden beneath Vostok Station. On June 20, 1996, the journal Nature reported this groundbreaking discovery.
Lake Vostok, as it became known, is separated from the surface by more than 2 miles (nearly 4 kilometers) of ice. While humans have never physically touched it, seismometers and ice-penetrating radar have provided us with a reliable understanding of the lake's features.
The lake is elongated in shape, stretching about 155 miles (250 kilometers) long, but only 31 to 50 miles (50 to 80 kilometers) wide. It has both a northern and a southern basin, with depths reaching as much as 2,600 feet (800 meters) in some areas. The lake holds approximately 1,300 cubic miles (5,400 cubic kilometers) of liquid water.
In addition, Lake Vostok has its own island and might even experience tides.
This is all fascinating, but it raises a critical question: How does any lake — no matter its size — remain unfrozen beneath a layer of ice taller than the tallest skyscraper?
All Warmed Up
Subglacial lakes require heat sources, and sometimes the Earth itself provides this heat.
Our planet emits geothermal energy, which radiates upward to melt the ice that is in contact with bedrock. This results in the accumulation of liquid water in valleys and other low-lying areas on the rocky surface.
Oddly enough, some ice sheets also generate heat. Ice naturally melts when subjected to enough pressure, and the immense weight of a thick, heavy ice sheet creates substantial pressure on the water molecules at its base.
The exact origins of Lake Vostok are somewhat unclear, but for the past 15 to 20 million years or so, the lake has been entombed beneath ice.
The Search for Life in the Lake
In 1999, scientists discovered microbes within ice samples taken just above Lake Vostok. This ice likely originated as water from the lake's surface that later froze to the glacier above it.
A 2013 investigation uncovered over 3,000 "unique gene sequences" in the subsurface ice surrounding Lake Vostok. Nearly half of these genetic sequences were identifiable, with around 94 percent originating from bacteria. The researchers also reported signs of more complex life forms, including fungi and tiny crustaceans.
Some critics of the 2013 study expressed concerns that contamination from the drilling tools might have tainted the ice samples. If true, the gene sequences could have come from outside environments rather than Lake Vostok itself. Nevertheless, lead author Scott Rogers has strongly refuted these claims.
On February 5, 2012, Russian scientists succeeded in drilling through nearly 2.5 miles (4 kilometers) of ice to reach Lake Vostok for the first time. Tragically, Andrey Kapitsa, who had pioneered much of the early research, passed away less than a year earlier.
Studying Lake Vostok and other subglacial habitats could provide valuable insights into the potential living conditions on distant moons, such as Jupiter's Europa or Saturn's Enceladus. Both of these moons feature liquid oceans beneath thick layers of ice, making them prime targets for humanity's search for extraterrestrial life.
The Antarctic Ice Sheet holds an incredible 70 percent of all the fresh water on Earth.
