The NASA Messenger Spacecraft has presented its discovery that Mercury has a lot of unfathomable lava flows that envelop the small planet's northern polar region with no other earth-type volcanoes in view.

Mercury's exterior portion have slopes just like the hills and valleys on Earth, but those of the smallest planet in the solar system are described as "hollows" to distinguish them from craters.

While the planet is described as having common features like the earth's surface, close-up images taken by the NASA space vessel prove otherwise.

The Messenger, according to a report from Reuters, stands for Mercury Surface, Space Environment, Geochemistry, and Ranging spacecraft. It went around the inner solar system 15 times during the past 6 years before it started orbiting around the planet on March 18.

This planet closest to the sun has a magnetic field, just as Earth, Jupiter, Saturn, Uranus and Neptune do, but "Mercury's magnetosphere is so small -- about 1 percent the size of Earth's -- that it offers little protection from the charged particles that make up the solar wind blasting off the Sun," the report from Reuters also cited.

"The deepest planet has had a long and much more exciting life than anyone expected or predicted," according to James Head III of Brown University.

The findings of Messenger were published in a special series of articles in the Journal of Science.

Astronomers have long speculated if Mercury had volcanoes on its surface which was recently confirmed by the NASA spacecraft.

However, no volcanoes are discernible and scientists suppose that the source of the lava has been buried under the flow.

The polar lava flow covers more than 6 percent of Mercury's surface, an area equivalent to 60 percent of the U.S.

"When the lava flowed out of cracks in the planet's surface some 3.5 billion to 4 billion years ago, it filled craters more than a mile deep," Head explained. The quantity would have been sufficient to submerge the state of Texas under a 4-mile deep blanket of lava.