On Friday, May 24, 2019 at 11:35:59 AM UTC-7, Mark Earnest wrote:
On Friday, May 24, 2019 at 11:49:38 AM UTC-5, palsing wrote:
And what, Mark, are snowballs made of, if not water?

Water and dirt but not near enough water to fill up an ocean.

So, Mark, how many comets would it take to fill up an ocean? Let's assume for this exercise that each comet is spherical and is 10 miles in diameter. Show your work.

As Hagar has already pointed out, the Oort Cloud is the likely source of many comets. How many, you ask? See this...

https://en.wikipedia.org/wiki/Oort_cloud

.... and read therein...

"The outer Oort cloud may have trillions of objects larger than 1 km (0.62 mi), and billions with absolute magnitudes brighter than 11 (corresponding to approximately 20-kilometre (12 mi) diameter), with neighboring objects tens of millions of kilometres apart. Its total mass is not known, but, assuming that Halley's Comet is a suitable prototype for comets within the outer Oort cloud, roughly the combined mass is 3×1025 kilograms (6.6×1025 lb), or five times that of Earth."

Read again "5 times that [the mass] of the Earth"

Does that sound like enough water?