Newsgroups: alt.sci.planetary
From: henry@spsystems.net (Henry Spencer)
Subject: Re: Question about orbiting Io.
Date: Sun, 5 Mar 2000 19:48:27 GMT

In article <uXGv4.355$VG6.10725@newsread1.prod.itd.earthlink.net>,
Ryan <rhino321@dontmailmewiththislinein.jps.net> wrote:
>Just a quick question, but would it be possible to put some type of probe
>into orbit about Io?

It's not utterly impossible, but quite difficult.  Getting there is a very
propulsion-intensive job, and the payload would be quite small unless you
used advanced propulsion.  Staying there for any length of time would be
terribly hard on the electronics.

>I sure radiation is probably the number one concern, so I am just curious as
>to how that would be done.  Would they need to build the entire exterior of
>the craft out of lead?

No, they'd either use radiation-hardened electronics which don't need
shielding, or put the electronics in a small heavily-shielded package,
with as much other stuff around it as possible.  (For example, you'd put
the batteries outside the shielding and use them to help.  Ditto any fuel
tanks.)

Lead would not be the shielding material of choice.  It's used on Earth
mostly because it's cheap, but there are more effective materials if
you're more concerned about mass than cost.  It's not an area I keep up
with, but I know tantalum has seen some use.

>That obviously would be alot of weight getting off
>the ground, but perhaps it's possible?

Oh, it's undoubtedly feasible -- at least for a short orbital mission --
if you wanted to do it badly enough.  It would be costly.
--
Computer disaster in February?  Oh, you |  Henry Spencer   henry@spsystems.net
must mean the release of Windows 2000.  |      (aka henry@zoo.toronto.edu)