Xref: utzoo sci.space:30568 sci.space.shuttle:7893
Newsgroups: sci.space,sci.space.shuttle
Path: utzoo!henry
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: space news from March 18 AW&ST
Message-ID: <1991May18.233028.24325@zoo.toronto.edu>
Date: Sat, 18 May 1991 23:30:28 GMT
References: <1991May10.034743.29351@zoo.toronto.edu> <1991May18.231158.24883@milton.u.washington.edu>
Organization: U of Toronto Zoology

In article <1991May18.231158.24883@milton.u.washington.edu> wiml@milton.u.washington.edu (William Lewis) writes:
>>offers a high enough exhaust velocity to make fast trajectories possible,
>                                               ^^^^^^^^^^^^^^^^^
>   What does a "fast trajectory" mean? Faster than a Hohmann orbit?

Yes, plus more amenable to short overall missions.  Using Hohmann orbits
for Earth-Mars-Earth is awkward because there is a *long* wait at Mars
for the return window.  Faster trajectories not only take less time
themselves, they give you more flexibility in planning the stay time.
-- 
And the bean-counter replied,           | Henry Spencer @ U of Toronto Zoology
"beans are more important".             |  henry@zoo.toronto.edu  utzoo!henry