Newsgroups: sci.space.shuttle
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: Shuttle-ground communication
Message-ID: <1989Mar20.191412.23335@utzoo.uucp>
Organization: U of Toronto Zoology
References: <2099@botter.cs.vu.nl>
Date: Mon, 20 Mar 89 19:14:12 GMT

In article <2099@botter.cs.vu.nl> wallagh@cs.vu.nl () writes:
>Until now, I've been told , only during 30% of the flighttime communication
>with the ground was possible...
> 
>Question: Why was it only 30% until now. I guess that when the shuttle flies
>over Rusia, there might be a gap in communication, but only 30%??? 
>Wheren't there any satelites upthere already, who could do the job?

For data relay as well as voice, it's not an entirely trivial job.  In the
beginning, launching a complete set of relay satellites for itself was to
be one of the shuttle's first jobs.  In practice, an upper-stage failure
on the first such launch delayed further ones until the problem could be
straightened out.  The second relay satellite was Challenger's payload.
-- 
Welcome to Mars!  Your         |     Henry Spencer at U of Toronto Zoology
passport and visa, comrade?    | uunet!attcan!utzoo!henry henry@zoo.toronto.edu