Newsgroups: sci.space.shuttle
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: Why STS-35 is being launched at night.
Message-ID: <1990May28.153022.20010@utzoo.uucp>
Organization: U of Toronto Zoology
References: <6282.266023d3@jetson.uh.edu>
Date: Mon, 28 May 90 15:30:22 GMT

In article <6282.266023d3@jetson.uh.edu> cheehh@jetson.uh.edu writes:
>  Apparently, the telescopes aboard Astro-1 will be at their best in
>the "night" phases on the orbit.  Also, they will be unable to function
>while the shuttle is in the North Atlantic Anomaly (NAA)...
> Does anyone have any comments/corrections about this?

Just one:  there is no North Atlantic Anomaly as far as I know.  The reference
is probably to the South Atlantic Anomaly, an area over the southern Atlantic
where the inner Van Allen belt is unusually close to the Earth.  It's a major
nuisance to spacecraft with sensitive detectors.

This fits with the night launch.  From a northern launch site, a night
launch into low-inclination orbit gives you an orbit with its northern
end on the night side of the Earth and its southern end on the day side.
-- 
As a user I'll take speed over|     Henry Spencer at U of Toronto Zoology
features any day. -A.Tanenbaum| uunet!attcan!utzoo!henry henry@zoo.toronto.edu