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Re: new web site/status report

At 4:37 PM 4/10/96, DotarSojat@aol.com wrote:
>On 4/10/96 at 10:35 am EDT, Kevin wrote-
>>(At 1G continuous thrust)...Even the antimatter rockets can't
>>get up to .99 lightspeed with a mass ratio of 52.
>Two points--
>1. With the saturation of apparent velocity, the implications
>of .99 lightspeed are obscured.  A peak apparent velocity of
>0.99 ltyr/yr represents a peak proper velocity of 7.0179
>ltyr/yr and an acceleration distance (at 1g) of 5.90 ltyr.
>(I.e., a destination distance of 11.8 ltyr with 1g deceleration,
>also.  BTW, my astronomy book gives the distance to tau Ceti as
>10.3+/-0.3 ltyr.)  What mass ratio does MARS require to decel-
>erate at 1g from this peak velocity?  (I think that's the 52,
>from Timothy's 3/30 table, that you're quoting, which is for
>100 percent conversion of captured microwave energy to exhaust
>kinetic energy.)
>2. An optimum antimatter rocket with a peak proper velocity Uend
>of 7.0179 ltyr/yr has an optimum constant exhaust velocity Vexh
>of 0.8851.  The required mass ratio (r = exp[asinh(Uend)/Vexh])
>is 19.89.  (These calculations assume no energy losses, but also
>assume no gain from optimizing the exhaust-velocity profile.)
>Regards, Rex

Can I assume the 19.89 mass ration is composed of 1/4th antimatter and
3/4ths reaction mass (normal matter)?


By the way the fusion fuel mass ratio I got for the Explorer Class was
about 55 to 1.  Since I thought the reaction mass ration for the MARS was
less, I don't know if 52 to 1 refers to that.  Unless the MARS number I was
remenbering was for a 1/3rd C decel?

By the way, I was wounderin.  DID ANYONE LOOK AT THE NEW WEB PAGES!!??  the
ones under Explorer_Class, Status_Report, and Support_Craft at Daves

Theres 50 - 60 pages of stuff up there so I expected some comment from


Kelly Starks                       Internet: kgstar@most.fw.hac.com
Sr. Systems Engineer
Magnavox Electronic Systems Company
(Magnavox URL: http://www.fw.hac.com/external.html)