A team of planetary scientists has proposed a new theory stating that the Moon, Earth’s natural satellite, has shifted off its original axis by roughly 6 degrees over the course of a billion years. This shift might have happened due to violent volcanic activity, nearly three billion years ago. Southern Methodist University, Dallas Planetary scientist Matt Siegler and his team has worked on the project.

After checking data collected by NASA missions, Siegler added giant mass of molten material could have caused a change in internal balance of lunar center of gravity. The study has been published in the journal Nature.

Scientists have long been trying to determine why Moon’s two regions harboring ice, one 6 degrees off its north pole and the other 6 degrees off its south pole, are there and not at the frigid poles with the rest of the natural satellite’s ice.

The new theory, proposed by a team of scientists from the Southern Methodist University, Dallas and some other institutions from around the globe, aims to answer that question.

Siegler added, "This was such a surprising discovery. We tend to think that objects in the sky have always been the way we view them, but in this case the face that is so familiar to us — the Man on the Moon — changed."

Ian Garrick-Bethell, a professor of planetary sciences at UC Santa Cruz, explained, “So that a line drawn from one end to the other would pass through the center of the moon … If a huge pile of lead weights suddenly appeared in New York, the city’s latitude would eventually shift to a position slightly southward because of planetary reorientation.”

The scientists also tried to explain what might have caused the space rock to rotate. A volcanic region active for billions of years during the Moon’s early history, called Procellarum, caused a change in the density distribution of the natural satellite, which resulted in reorientation when it was still young.

If the newly proposed theory is found to be right, it would mean that water could have been present on the Moon since very early in its history of 4.5 billion years. Currently, scientists believe that water was delivered to the Moon more recently by asteroid impacts.