# Re: MARS HYBRID DESIGN II (First Draft)

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Brian 12:35 PM CT 3/5/96
>
> >Kelly Starks x7066 MS 10-39 wrote:
> > Pluto moves MUCH faster than Earth.  Your mirror would quickly move out
of
> > the beam.  even if the beam was larger than Earths orbit.
>
> >David
> >Pluto's mean orbital velocity is 4.74 km/sec.
> >Earth's mean orbital velocity is 29.79 km/sec.
>
> Why is the mean orbital velocity of Pluto 4.74 compared to a much larger
> 29.79.  Did you get the numbers mixed up.   I'm confused.

>David
>Nope, you can even do the math yourself.  I got the numbers
>from the LANL solar system web site, though.  Let's see if
>we can do this ourselves:

>Earth orbits at around 148,800,000 km from the sun, right?
>That's a circumference of 934,937,974 km.  It does this
>in around 365.25 days, or 31,557,600 seconds.  That gives us
>29.63 km/sec.  Pretty close to the LANL value.  I assumed
>it was a perfect circle, and it's not.  Okay, now let's try
>Pluto.  It orbits at 5,913,520,000 km (around 39.74 AU).
>It revolves around the sun once every 248.54 years, or
>7,843,325,904 seconds.  The circumference of Pluto's orbit
>is 37,155,741,978 km.  That gives us 4.74 km/sec.  Wow,
>dead on to LANL's value.  I must say I'm impressed,
>especially considering the eccentricity of Pluto's orbit.
>I assume the mean distance value is for an "equivalent circle".
>That would explain the accuracy of my results.

Brian
So Pluto does go slower?

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