Wednesday, May 29, 2013

Destiny

So if you were the Captain of a crippled ship, with only one island within range before your vessel surely sinks, what would you name it? 

Captain Dayson names the single K4 class orange dwarf star her crew finds to be close enough to reach "Destiny".  Disclaimer:  Names may be changed at any time if the author finds them too hokey. 

Destiny
Class:  K4 class orange dwarf star
Absolute Magnitude:  7.1
Lifespan:  40-60 billion years.
Luminosity:  .18 Sol

Mass:  .71 Sol
Diameter:  .69 Sol  The diameter of the Sun is 1,392,000km, so the diameter of Destiny is 960,000km. 

With a star of this size and luminosity, a planet would have to orbit at .43AU to receive the same energy from this star as Earth does from the Sun. 

DISCLAIMER:  I'm not an astronomer or a mathematician.  Please feel free to correct me.

The formula for determining if a star is visible to the naked eye is:

m = M - 5 ( 1 - log10 D )

m is the apparent magnitude (invisible to the naked eye if number is greater than 6)
M is the absolute magnitude
D is the standard measuring distance of brightness of 10 parsecs.  A parsec is 3.26 light-years

In my book the crew of the Michael Stennis first observe Destiny from 82 light years.  Is the star visible to the naked eye?  Nope.  Our Sun, five times as bright as Destiny, is visible to the naked eye out to about 55 light years, or 16.87 parsecs.  Destiny would be invisible without a telescope much closer than 55 light years. 

If my math is right (very questionable), at 82 light years the apparent magnitude of Destiny would be 9.1, far above the 6 that limits the visibility of a celestial object to the naked eye. In fact, a magnitude 10 star is at the limit of  7x50 binoculars.  So Destiny is dim indeed. 

Please feel free to offer any corrections or suggestions. 

Tomorrow I will describe the Destiny solar system and I'll slaughter the math involved there too.





1 comment:

  1. As you can see, the names evolve as time passes. I try to step back from the too cliche names, although let's face it, that's what people do, that's why it's cliche.

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