John,Thanks for the clarification. Yes I see that using the meter (or its
powers to the ten) could preserve scale that the terms astronomical units or
parsecs don't.
It would be nice to see metric units used more often with inter-stellar
systems. I wonder why they aren't used more often. I'm sure there are at least
a few astrophysicists and astronomers who are metric-conversant.
Anyways I'll keep looking at this--I realize there is a massive scale here,
going from our own solar system all the way up to the 92 billion
light-year-wide--err... that is, 900 billion petameter-wide universe, so it it
very well might be the case that metrically-minded astronomers might want to
use two metric prefixes (one for shorter and the other for longer distances).
Are gigameters and petameters the two most commonly used ultra-metric
measurements?
[USMA:50264] re: astronomical measurementsJohn M. Steele
Sun, 03 Apr 2011 07:41:49 -0700No. I find comparing in meters (with a suitable
prefix) gives me a better
sense
of scale than mixing AU, light years, parsecs, and other obscure units with
obscure inter-relationships. Determining that a light year is some 63000 AU is
not particularly helpful.
As a general comparison, it is much easier to learn a few metric prefixes,
usable with all units, to provide a short hand alternative to scientific
notation for scale than to learn all the absurd interrelationships of Customary
units.
