The Weekly Shtikle - Vayeira

This week's shtikle is dedicated le'ilui nishmas my brother Efrayim Yechezkel ben Avi Mori Reuven Pinchas whose Yahrtzeit is this Sunday, the 18^th of Cheshvan.

Rashi on 19:24 notes that the destruction of Sedom happened at day break, when the sun and moon were in the sky at the same time. This was because they used to worship the sun and moon. HaShem therefore brought the destruction when both were out as a proof to all the sun and moon worshipers that the sun and moon are powerless. Had the destruction taken place when they were not in the sky, one could have argued that they were not "there" to save them. This is a rather simple statement by Rashi but the astronomical basis for it is quite interesting.

It is not always that the sun and moon are out together at day break. It is also not always that it is the only time that they are out together. The moon's rising and setting times occur approximately 48 minutes later each day. This is a result of the moon orbiting  the earth. Just as the moon's position is reset at the end of every month, so are its rising and setting times. (The figure of 48 minutes is achieved by dividing 24 hours by the length of the month, 29.5 days, 44 minutes, 3 and a third seconds. More precisely, the figure is 48 minutes, 45.5 seconds.) At the beginning of the month, the moon follows a very similar schedule to the sun. The moon rises at the beginning of the day and sets at sundown. As the month progresses, the moon rises and sets later and later. At the middle of the month, the moon has virtually the opposite schedule to the sun. It rises when the sun sets and sets when the sun rises. As we enter the second half of the month, the moon begins to rise later in the night and thus, becomes visible at the beginning of the day.

The Midrash (Bereishis Rabba 50) teaches that Sedom was destroyed on the 16th of Nissan. As explained, at that time of the month, the moon would have set very shortly after sunrise. Therefore, the only time in the entire day that both the sun and moon were out at the same time was very early in the morning and that is why the destruction took place specifically at the very beginning of the day. [Nevertheless, it is puzzling that Rashi uses the term "Alos HaShachar" which refers to a time before sunrise.]

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Have a good Shabbos.

Eliezer Bulka
EzBulka@hotmail.com
http://weeklyshtikle.blogspot.com
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