Are snowflakes really all unique?
When I was growing up, the party line was “all snowflakes are unique” and they never repeat. I accepted that when I was 10 years old.
But in thinking about the purported megastorm in New England tomorrow, I wonder. We’re talking about 24+ inches of snow over several thousand square miles of the US.
Is it really possible that not one of the zillions of snowflakes is a duplicate of another?
Observing members:
0
Composing members:
0
6 Answers
Yes.
Two snow flakes can be exactly alike, they can even produce identical snowflakes in labs, what the saying is implying is that by the time they reach you, they are melted/distorted/different enough to not be exactly identical, but the fact is there are only so many types of snow flakes.
@gailcalled That is a great link. I had not considered the effect of O16 vs O18 and Deuterium. I thought the difference was just due to the micro-climate where the crystal formed. In a lab it is possible to make 2 snowflakes that look alike, but to truly BE alike we need to fIgure all the isotopes of each molecule.
From the link above:
“If we restrict ourselves to water molecules which contain two ordinary hydrogen atoms and one ordinary 16O atom, then again physics tells us that all such water molecules are exactly alike. However about one molecule out of every 5000 naturally occurring water molecules will contain an atom of deuterium in place of one of the hydrogens, and about one in 500 will contain an atom of 18O instead of the more common 16O. These rogues are not exactly the same as their more common cousins.
Since a typical small snow crystal might contain 1018 water molecules, we see that about 1015 of these molecules will be different from the rest. These unusual molecules will be randomly scattered throughout the snow crystal, giving it a unique design. The probability that two snow crystals would have exactly the same layout of these molecules is very, very, very small. Even with 10^24 crystals per year, the odds of it happening within the lifetime of the Universe is indistinguishable from zero.”
Cal. Tech gets all the credit.
Answer this question 
This question is in the General Section. Responses must be helpful and on-topic.
Composing members:
0
