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Re: Planet X: MAGNITUDE Clarification 2


Magnus Nyborg wrote:
>In Article <3B1261B3.90C0B686@zetatalk.com> Nancy Lieder wrote:
>> - given that the Sun is considered to be magnitude 4.85
>
> You are only about 32.85 magnitudes off, with the Sun
> actually being magnitude -28, a factor of almost 14000
> billion times...close, but no cigar!

Gee, S. Welknelk stated it was 4.85, and no one objected.  Can we all
get on the same page here?

In Article 
>Why all the BS about the difference between ABSOLUTE
>magnitude and APPARENT magnitude? Our own sun has an
>ABSOLUTE magnitude of +4.85 (if viewed from 10
>parsecs distance from earth, standard definition).

David Knisely wrote:
>Absolute Magnitude is defined as the magnitude a
>light-emitting object would show if it were 10 parsecs
>(32.6 light years) away from the observer.  The only
>solar-system object which would be visible at 10 parsecs
>(at least to the eye) would be the sun, and it would be
>magnitude 4.82 at that distance.  Some comets or
>asteroids can be given a sort of "1-AU" magnitude
>(the brightness as seen at 1 astronomical unit away
>from the sun and the observer), but the term Absolute
>Magnitude is generally reserved for the 10 parsec
>distance.