In November of 2018, scientists revealed that they had discovered a 19-mile wide impact crater below the ice in Northwest Greenland, called the Hiawatha impact crater. The crater was the first of its kind, found under one of the earth’s continental ice sheets.
Scientists have now uncovered another impact crater underneath a mile of ice about one hundred miles from the Hiawatha crater, according to a study led by NASA glaciologist Joseph MacGregor that was recently released in Geophysical Research Letters.
Joseph revealed in the study that it has become very rare to find any previously undiscovered impact craters on Earth, much less to find one buried so deeply under the ice.
This particular crater has a diameter of twenty two miles, making it even larger than its neighbor, the Hiawatha. It’s not certain that this is, in fact, an impact crater but researchers feel confident enough in the site’s shape and geophysical makeup to categorize it as one.
If this crater was made by a falling meteorite, it will be the second of its kind to be found under ice sheets in Greenland or Antarctica. It will be the 22nd largest impact crater currently known on Earth.
Both craters were discovered with the help of MacGregor, who stated that he was excited that new discoveries were still possible after having surveyed the earth at length from space, air and land. Prior to discovering Hiawatha, it had historically been believed that any impact craters in Greenland would have been destroyed by the moving and eroding forces of ice.
When the team discovered Hiawatha, they decided it was possible that more craters may exist under the ice. The scientific team studied the topography of the terrain under the sheets of ice in Greenland and compared them with the ice surfaces in data gathered by satellite.
One hundred and fourteen miles to the southeast of Hiawatha, they discovered a circular pattern and suspected it may have been an impact crater. MacGregor asked himself if his research and findings could support the idea; having already discovered one crater below the ice was amazing enough, but to find two was unheard of.
Initially, MacGregor considered the idea that the circular area was a collapsed volcano, but he realized that all volcanic activity in Greenland was hundreds of miles from the site. He was also unable to see any evidence of positive magnetic anomaly that typically accompanies volcanic sites.