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A sense of scale 
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Heinlein Nexus
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Post A sense of scale
The ol' Powers of Ten... in a wonderful new interactive presentation: http://htwins.net/scale2/scale2.swf?bordercolor=white


Tue May 15, 2012 10:57 am
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Post Re: A sense of scale
Very cool, thanks! It is interesting to see Pluto compared side-by-side to other objects, which makes clear why it's not called a planet anymore. I still think of it with great affection, though. ;)

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Wed May 16, 2012 8:22 am
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Post Re: A sense of scale
I'd still go with planet, since it doesn't orbit anything but the sun. But that's just me.


Wed May 16, 2012 9:41 am
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Post Re: A sense of scale
When is a planet not a planet? When it is a "dwarf planet". I have never figured that one out!


Wed May 16, 2012 9:44 am
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Post Re: A sense of scale
Some astronomer whose name I forget said, wrt Pluto, that "No object that would have a tail in the inner solar system should be called a planet." That seems to be the reasoning of most astronomers that supported the idea of "dwarf planets" and wanted to demote Pluto.

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Wed May 16, 2012 10:49 am
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Post Re: A sense of scale
DavidWrightSr wrote:
When is a planet not a planet? When it is a "dwarf planet". I have never figured that one out!

A dwarf planet circles the sun (unlike a moon), is large enough for gravity to have pulled it into an ellipsoid shape (unlike a comet or most asteroids), but hasn't cleared its orbit of other objects (unlike a planet).

Basically, the discovery of Eris in 2005, and the realization that perhaps many more objects larger than Pluto were going to be found in the future encouraged these new definitions. I suspect that the definitions (which are a little bit strained) were jiggered until astronomers were pretty sure that no new planets would be found.

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Wed May 23, 2012 1:04 pm
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Post Re: A sense of scale
LilLeaguer wrote:
A dwarf planet circles the sun (unlike a moon), is large enough for gravity to have pulled it into an ellipsoid shape (unlike a comet or most asteroids), but hasn't cleared its orbit of other objects (unlike a planet).

Next up: the definitive definition of sf vs. fantasy.

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Wed May 23, 2012 1:08 pm
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Post Re: A sense of scale
JamesGifford wrote:
Next up: the definitive definition of sf vs. fantasy.


Oh, Jim, they settled that too, ages ago: http://en.wikipedia.org/wiki/Science_fa ... ce_fiction .

See how much thinking that saves you from?


Wed May 23, 2012 1:29 pm
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Post Re: A sense of scale
Science fiction is what I like. Fantasy is what I don't like. Thus, Heinlein never wrote any fantasy.

See how much thinking this, too, saves us from? :lol:

QED

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Wed May 23, 2012 1:51 pm
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Post Re: A sense of scale
RobertPearson wrote:
Science fiction is what I like. Fantasy is what I don't like. Thus, Heinlein never wrote any fantasy.

See how much thinking this, too, saves us from? :lol:

QED


You never read Glory Road? Or The Unpleasant Profession of Jonathan Hoag?


Fri May 25, 2012 5:09 pm
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