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From: kenny@uiucdcsb.cs.uiuc.edu
Newsgroups: sci.space
Subject: Re: space news from AW&ST 6 Oct 1986
Message-ID: <163400002@uiucdcsb>
Date: Tue, 18-Nov-86 13:31:00 EST
Article-I.D.: uiucdcsb.163400002
Posted: Tue Nov 18 13:31:00 1986
Date-Received: Wed, 19-Nov-86 22:18:04 EST
References: <7325@utzoo.UUCP>
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Nf-ID: #R:utzoo.UUCP:7325:uiucdcsb:163400002:000:1324
Nf-From: uiucdcsb.cs.uiuc.edu!kenny    Nov 18 12:31:00 1986


In article <7325@utzoo.UUCP> henry@utzoo.UUCP (Henry Spencer) writes:
>[Mini-editorial:  a probe with a 50-year mission will be passed by newer
>probes with better engines long before the end of its mission.  Planning
>for such long missions needs to consider in-flight obsolescence.  -- HS]
Then good@pixar.UUCP replies:
>Good point.  But better engines will result, at least in part, from experience
>gained by flying the current idea of "new" engines.  I also wonder if the
>probe might not return some data significant for the planning of a follow-up
>mission during the first few years.

More to the point, the fact that a probe is obsolescent doesn't mean
that it's necessarily useless.  A case in point are the early Pioneer
spacecraft.  As of two years ago (the last I heard from any of the
Ames people on the project), all of the civilian Pioneers (the first
four were built while JPL was still a military shop) were still
functioning and returning useful plasma-physics data.  The oldest is
nearing 25 years of service.

Kevin Kenny			     UUCP: {ihnp4,pur-ee,convex}!uiucdcs!kenny
University of Illinois at Urbana-Champaign	       CSNET: kenny@UIUC.CSNET
NSA line eater food:               ARPA: kenny@B.CS.UIUC.EDU (kenny@UIUC.ARPA)
    Bomb, secret, terrorist, cryptography, DES, assassinate, decode, CIA, NRO.