Re: LM question

From: Philip Lantz (_at_ibeam)
Date: 03/12/05 

Date: Fri, 11 Mar 2005 17:36:34 -0800

Henry Spencer wrote:
>
> In article <p5gs21hik5un8dpnb7td9vpos8lq5fiogo@4ax.com>,
> Kelly McDonald <kellymcdonald@<no-spam> wrote:
> >
> >Talking about launch windows, what was the criteria involved in
> >determining them? Were they based on mission rules, or orbital
> >mechanics? Did they vary based on planned landing location?
>
> For the early flights, the main issue was sun angle at the landing site:
> to have the Sun low on the horizon (so surface obstacles would cast
> conspicuous shadows) behind the LM (so the pilot could see the LM's shadow
> on the surface, giving him a sense of scale on terrain with no familiar
> objects) required landing soon after dawn at the landing site. So the
> windows came once a month for any particular site.

How long was the launch window for a single site? Was the sun angle
within the range they were looking for for only a single day?

Philip Lantz