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A comment on Planet Ceres is an 'ocean world' with sea water beneath surface, mission finds. Parent comment

Re:Planet Ceres is an 'ocean world' with sea water beneath s... by lopmotr on Wednesday August 12, 2020 @12:57AM (#24128716)
We have to assume something about the accuracy otherwise there might as well not be any numbers at all! What if it was +/- 100 K ?

Writing 2 extra decimal places is assuming the original values also have 2 decimal places with zeros in them.

It's reasonable to assume the digits the author gave are correct and there are no other unwritten zeros after them. Even if the scientists really did measure 110.00 - 155.00 K, the author of the source document decided to remove that information and we don't know what it "really" was so we shouldn't guess.

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Re:Planet Ceres is an 'ocean world' with sea water beneath s... by KMag on Wednesday August 12, 2020 @06:19AM (#24130340)
> Writing 2 extra decimal places is assuming the original values also have 2 decimal places with zeros in them.

As long as you have at least one digit of precision, scientific notation is unambiguous as to the number of significant figures.

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Re:Planet Ceres is an 'ocean world' with sea water beneath s... by lopmotr on Friday August 14, 2020 @08:35PM (#24164878)
Yes, but these figures weren't written in scientific notation so we can't tell. Especially the trailing 0 on 110 is ambiguous because people often write a 0 there where it really is 0 while the convention is that a 0 means it's unknown.
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