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From: neal@lynx.uucp (Neal Woodall)
Newsgroups: sci.space
Subject: Re: Where the hell are electric-ion thrusters????
Summary: Why is mercury used?
Message-ID: <6096@lynx.UUCP>
Date: 29 Aug 89 18:19:41 GMT
References: <8908241857.AA02943@fermat.Mayo.edu> <1989Aug25.183710.3054@utzoo.uucp> <4256@utastro.UUCP> <6091@lynx.UUCP> <4271@utastro.UUCP>
Reply-To: neal@lynx.UUCP (Neal Woodall)
Distribution: usa
Organization: Lynx Real-Time Systems Inc, Campbell CA
Lines: 21

In article <4271@utastro.UUCP> terry@astro.UUCP (Terry Hancock) writes:

>The most powerful Ion drive designed and built (to my
>knowledge) is the 30-centimeter-diameter thruster developed at
>NASA Lewis Research Center:
>It uses electrostatically accelerated mercury (cesium would
>by bad news, by the way, it's both very reactive, and radioactive),
>mercury will just give you heavy metal poisoning if you ingest it.  

Any reason why the eletric-ion thruster must use mercury as the
reaction mass? Is it possible to develop a thruster that would
use a less expensive and dangerous material for reaction mass?
Is mercury used simply because it has a high atomic weight?







Neal