[Avodah] Rambam Hilchot Kiddush Hachodesh

[Ben Waxman]

1) Rambam Hilchot Kiddush Hachodesh 3:1 makes it clear that anyone who 
sees the new moon and can get to Jerusalem by the following evening 
should go. How would that work today given that basically means that 
every male in Israel who sees the moon should go (maybe men in Eilat who 
don't own a car would be patur). Were most (or even a small minority of) 
Israeli Jewish males above the age of 13 to look, there is no way that 
the Beit Din could even question all of these men, even if they only 
asked a couple of questions.

Is there any problem in making sure that you don't see the moon? Just 
stay in for the evening. Rambam doesn't say that there is a chiyuv to look.

Or since the Beit Din only takes testimony from trusted witnesses, can 
someone just say "I never got any type of certification that I am a good 
witness, therefore I don't need to go".

Or how about having a few (say 100) men in each major city or region 
entrusted with the job and they would be the designated possible witnesses.

2) Rambam Hilchot Kiddush Hachodes 2:10 says clearly that once the beit 
din declares the new month, that is it, even if they know that they made 
a mistake. Yet in 3:15 and 16 Rambam writes that in the situation where 
no witnesses came on the 30th, if witnesses come later in the month and 
are able to prove that they did see the moon come out on the 29th, that 
month's calendar is redone. Is this not an obvious contradiction? I 
assume that I am reading 3:15 and 16 incorrectly or that I am getting 
something wrong here.

3) Later in the book Rambam goes on at length and in extreme detail 
about how to calculate the moon's position. He adds that we know these 
calculations from science and that since we no longer have a tradition 
about this matter from the nevi'im, it is fine to use outside sources. 
Seeing this made me wonder why we don't apply this rule in other areas. 
For example, I had read that we don't make matza from barley because we 
don't have a tradition as to how it takes barley to become chameitz. So 
why not measure it?

Ben