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Re: new web site/status report
- To: T.L.G.vanderLinden@student.utwente.nl, kgstar@most.fw.hac.com, stevev@efn.org, jim@bogie2.bio.purdue.edu, KellySt@aol.com, zkulpa@zmit1.ippt.gov.pl, hous0042@maroon.tc.umn.edu, rddesign@wolfenet.com, David@interworld.com, lparker@destin.gulfnet.com
- Subject: Re: new web site/status report
- From: DotarSojat@aol.com
- Date: Wed, 10 Apr 1996 16:37:04 -0400
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