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NASA has discovered what it believes may be an enormous impact crater from a meteorite strike hidden under Greenland's ice.

"It is increasingly rare to find new large impact craters on Earth, let alone such craters buried beneath ice," the US space agency said.

But in a new study published in the journal Geophysical Research Letters that is exactly what the NASA scientists believe they have done.

Using satellite data and radar measurements taken by planes, the team mapped out a crater more than 36km (22 miles) wide and buried beneath 2km (1.2 miles) of ice in northwest Greenland.

It lies just 183km (114 miles) away from another newly-found crater in northwest Greenland, the Hiawatha crater - measuring 31km wide (19 miles) which may be as young as 12,000 years.

The new crater could be the 22nd largest crater on Earth, with the largest being the Vredefort crater in South Africa, which measured more than 300km across when it was formed.

The Vredefort crater is believed to be just over two billion years old, with the Earth thought to be just over 4.5 billion years old.

The next largest crater, the Chicxulub crater beneath the Yucatan Peninsula in Mexico, is much younger and about half as wide, measuring 150km and dating back only 66 million years.

However, the Chicxulub crater is believed to be the site of the meteor impact which caused the mass extinction of three quarters of life on Earth - including the dinosaurs.

The researchers had to establish whether the potential new crater was related to the Hiawatha impact crater.

Although they are similarly sized, the second crater appears more eroded, according to the team.

Tied to this, the ice above the impact site is much less disturbed than the ice above the Hiawatha impact crater.

According to the NASA scientists' statistical analysis, the frequency of two unrelated but nearby large impacts indicates that it is improbable but not impossible that this pair is unrelated.

However what that relationship could be has not yet been established.