How far is Pluto from the Sun? The Solar System has a radius of two light years.
"At the heart of the great cluster,where the nebula was so thick as to be a nearly featureless glow, pearl-hued and shot with rainbows, the stars were themselves so close that thousands could be seen." (p. 772)
"'Everything astronomical in abundance, close together and interacting.'" (p. 773)
I have tried to quote and summarize to convey Poul Anderson's account of the Cloud Universe but there is no substitute for reading or rereading "Starfog." The Cloud Universe is both a cluster and a nebula.
3 comments:
Kaor, Paul!
A light year is defined as the distance traveled by light in vacuum in one Julian year, 9.5 trillion kilometers. The closest star to Earth, Alpha Centauri, is 4.3 light years from Sol. I'm trying to imagine what it would be like to have a dozen or more stars barely as far away from Earth as the orbit of Pluto. It would certainly have had drastic effects on Earth!
I have wished Alpha Centauri and Barnard's Star had been only two light years from Earth. Because it then would not have been too hard to reach them even at our current, unsatisfactory level of space technology.
Sean
Pluto ranges from about 4 to 7 light *hours* from the sun.
I think that 2 light year figure is an estimate of the farthest any comets go from the sun and still return. It makes sense that if a comet gets farther than that from the sun the gravity of another star will pull it away from the sun.
Kaor, Jim!
That makes sense to me as well.
Ad astra! Sean
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