It is because of the giant Jupiter and Saturn planets that Earth has life today, according to new scientific findings based on certain simulations.

The simulations show that these two planets protected many other planets in the solar system including the Earth, from being hit by massive, fast-moving objects, reports If these giant systems were not there in the system, it would have been a “very, very different planetary system,” says Tom Barclay, of NASA's Ames Research Center in Moffett Field, California.

Barclay and his team found that giant impacts of the kind that led to the formation of the moon 4.5 billion years ago would take place more frequently, and over longer periods of time, if the solar system did not have giant outer planets. Such massive impacts, in turn, would lead to loss of atmosphere for the Earth, making it uninhabitable, says Barclay.

With giant planets, the last impact took place sometime between 10 and 100 million years ago. However, ,in the absence of these giant planets, the last impact would have occurred much closer back, according to Barclay.

Barclay’s team began the simulations after the formation of planet embryos the size of Mars. They used the simulations to study instances with and without the presence of giant planets on the outer perimeter of the solar system.

They found that in the absence of giant planets the fragments resulting from an impact form a huge cloud in the solar system which takes much longer to disperse, making the planet inhabitable.

Meanwhile, another research suggests that there could be abundant life in the universe, reports the Daily Galaxy. Scientists at UCLA have found evidence that life could have existed on Earth at least 4.1 billion years ago. This indicates that life came to Earth 300 million years earlier than previous research suggested.

In fact, this suggests that life may have begun shortly after the planet formed 4.54 billion years ago, according to the study findings, published in the online edition of the journal Proceedings of the National Academy of Science.