According to the findings of a study published in the Wednesday edition of the journal Nature, of all the comets that humans are aware of, Comet Hartley 2 seemingly contains water which is more like the water found on the Earth!

With the help of the Herschel space telescope, the study chiefly aimed at measuring the extent of the presence of deuterium – which is a rare kind of hydrogen - in Comet Hartley 2’s water.

It was found that, quite akin to the deuterium content in the water of Earth’s oceans, the amount of deuterium in the water of Comet Hartley 2 was half the amount of deuterium that is found in the other comets.

The observation apparently is an indication that a large part of the Earth's water may have initially come from cometary impacts. It is believed that some million years after the Earth was formed, its surface was rocky and dry; and it appears as if ‘something’ brought the water which now covers the maximum part of the planet.

Noting that the findings of the study signal the likelihood that comets at least contributed to the Earth’s water supply, researcher Ted Bergin - of the University of Michigan -, told BBC News: “The reservoir of Earth ocean-like material is much larger than we thought, and it encompasses cometary material, which we hadn't recognised.”