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> While the moon is an estimated 2,159 miles (3,475 km) in diameter [...] Is the article implying that we don't know the Moon's (I assume they're referring to
by lxgr 2y ago
> While the moon is an estimated 2,159 miles (3,475 km) in diameter [...]
Is the article implying that we don't know the Moon's (I assume they're referring to the capital-M one) diameter to at least kilometer-precision...?
- mattficke 2y agoIt’s an irregularly shaped body so there’s not one single radius. Mean radius is always going to be an approximation (even for Earth); the mean radius of the Moon is 1,737.4 km.
- lxgr 2y agoBut it's still an approximation, not an estimate, right? (The fact that you can list the mean radius with sub-decimal precision suggests as much.) To me, an estimate suggests that there's error bars; an approximation suggests that there's variance that we can quantify (or at least we're very confident about our error bars).
- feoren 2y agoThere are error bars on absolutely everything that we ever measure.
- lxgr 2y agoSorry, missed a "large". It would sound pretty strange to me to claim that the distance between New York and London is "an estimated x kilometers" (with single-kilometer precision), even though there is tectonic movement etc.