Water is present throughout our solar system – not only is the earth awash with it, but it is found on icy comets, on the moon and in the permanently shadowed basins of Mercury and Mars.
So – where did it come from? And why does it matter?
Scientists have wanted to know the answer to the first question because the second question is a no-brainer – it matters because it will tell them something crucial about the likelihood of life existing elsewhere.
If the water in the solar system came about as a result of chemical processes during the birth of the sun, it means other planetary systems may have much less water, which in turn would have implications for the potential emergence of life.
If, however, the water in the early solar system came primarily from ice in interstellar space – it is likely that similar ices, along with the prebiotic organic matter they contain, are abundant in every planetary system.
Without getting into the technical details, suffice it to say that scientists have found that at least some of the water in our solar system originated in interstellar space and pre-dates the birth of the sun. So – abundant, organic-rich interstellar ices can probably be found in all young planetary systems….
Which just begs the question – where did all that ice come from originally?