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Re: FYI: AoA's News release on MH '99 (dumb)

> > Parsec: a unit of steller distance, equal to about 3.25 light years (3.08 *
> > 10^16 metres), the distance at which the mean radius of the earth's orbit
> > subtends an angle of one second of arc.
> >
> > I don't understand it either. *s*

oops, I got my angle backwards.  the vertex is at the distant object. 

At a distance of one parsec the angle between the lines from it to the
earth, six months apart, is one second of arc (one 3600th of a degree)

it has to be the correct six months, of course, the two opposite
measurements have to be on a line perpendicular to the direction of the
distant point...

MAC: this is also useful for determining the distance of ofcifers
operating radar guns.  Don't ask me how.

Huw Powell


82 Audi Coupe; 84 4kq; 85 Coupe GT; 73 F250