Friday, October 24, 2025

Interesting Calendrical Facts About the Mabul

We are taught that the Mabul began at midday. (Bereishis 7:13) Rashi cites that the reason for this was to demonstrate that, with Hashem's protection, Noach was able to enter the Teivah in front of all the wicked people of his generation and none of them was able to harm him.

Rav Yehonasan Eibshitz zt"l offers an additional explanation that has to do with the way the calendar works. Rav Eibshitz mentions that the historic date which the dove found dry land in the year after the Mabul was the first of the first month and was a Shabbos. If so, then the year preceding this one, the year when the Mabul began, the first day of the first month was Tuesday. (Clearly Rav Eibshitz is using a regualry styled year in which half the months contain 30 days and the other half have 29. The months alternate with 30 then 29 and so forth throughout the year.) Since the first month was a Tuesday then the subsequent month, the month in which the Mabul started, started on a Thursday. Thus, the 17th of that month, the day which the Mabul started, was Shabbos. Since the Gemara teaches that rain on Friday night is a blessing, the rain, instead, began during the daytime as not to give the wicked people even one iota of blessing. (Taanis 23a) Rav Eibshitz continues that, additionally, the mazal of Shabbos daytime is Saturn which symbolizes mass destruction and that was befitting for the beginning of the Mabul. (See Rashi Berachos 59b and the Ibn Ezra's Reishis Chachma) (Tiferes Yehonasan Bereishis 7:13)

The World's First Boat?

For 100 years Noach toiled and endured much ridicule from his neighbours as he built the ark. Sure enough, Noach had the last laugh when the flood finally came and wiped out everyone else on the planet. Having completely denigrated Noach and ignored his warnings, the people were completely unprepared. However, the ark was nothing more than a large boat. Didn’t anyone have a boat of their own to escape the destruction of the flood?

This fascinating question was asked of me by R’ Sander Goldberg of Baltimore and he followed it up with a fascinating answer from his sefer נחל חיים (Page 30.) There is some discussion regarding the general climate and environmental conditions before the flood and how they were changed forever by the flood. One of the principal catalysts for these theories is the first reference to seasons after the flood (8:22) which seems to imply that there were no seasons beforehand.


מלבי"ם writes that before the flood planet Earth was not on the 23.5 degree tilt on which it finds itself currently. The tilt was as direct consequence of the environmental havoc wreaked by the flood. When the earth is not tilted the climate conditions throughtout the world are at complete equilibrium. That is to say that weather conditions are completely uniform throughout the world and throughout the year. There is simply no reason for conditions to be any different in one place from another. Cloud cover as we know it did not exist either. After all, a partially cloudy sky means that there are clouds over one part of the land and not over the other. Rather, the skies slowly became saturated with moisture uniformly and once every forty years, writes מלבי"ם, the entire earth would be drenched with rain and the process would begin anew. (This explains why the people were not overly taken aback by the flood when it began.) מלבי"ם also attributes the longer lives lived before the flood to the consistency of the climate.

(Now THAT's climate change!)

Another condition that would result from a world climate in equilibrium is uniform atmospheric pressure. Without varying pressure, there can be no wind. Wind is a result of air moving from a high pressure area to a lower pressure area like the air flowing out of a balloon. Before the age of the motor, all large boats relied on wind to move. If there were no wind, there would have been no boats. This explains why Noach’s project appeared so strange and also explains why no one else had any means to survive the flood.

(He goes on to explain that due to this extreme difference in global climate fermentation was something that did not happen before the flood and that explains how Noach could go so terribly wrong afterwards getting drunk - alcohol hadn't existed either.)

Friday, August 1, 2025

Like the Stars of the Heavens


As part of Moshe Rabbeinu's introduction to his review of the last forty years, he makes mention of the fact that (1:10) "HaShem has allowed you to multiply and you are now numerous like the stars in the sky." Rashi is bothered by the obvious exaggeration. B'nei Yisroel were a nation of merely 600,000 men which is infinitesimal compared to the infinite stars. Rashi offers an alternate understanding of the pasuk. However, I believe it is possible that Moshe was indeed comparing B'nei Yisroel to the stars in the sky at that very time.

This understanding is based on a commentary of R' Chayim Kanievsky in Parshas Lech Lecha (Bereishis 15:5). HaShem brings Avraham Avinu outside and tells him to observe the uncountable stars and tells him that his progeny will be likewise uncountable. Rashi there quotes a Midrash that states that HaShem removed Avraham from the atmosphere and placed him above the stars to observe them. R' Chayim questions, why was this necessary? Why was it not sufficient to simply look at the stars from where he was? He answers that we are taught in the adjacent commentary to Rambam's Hilchos Yesodei HaTorah (3:8) that there are a finite number of stars visible from Earth, 1022 to be exact. Beyond the scope of our vision there exists an abundance of stars which are too many to be counted. Avraham had to be removed from Earth in order to appreciate that.

Therefore, when Moshe Rabbeinu spoke to B'nei Yisroel, they were very much comparable to the stars in the sky. In a very short time, B'nei Yisroel had indeed multiplied from a mere 70 to an impressive 600,000. Like the stars that are visible from Earth, they were great in number, yet still countable.

The word "larov" here is assumed to mean "for multitudes" which would imply that the multitudes have already been achieved. This is what is bothering Rashi. While this is, in fact, the meaning of the word in most of its many occurrence in Tanach, it may also be used as a verb, to multiply (as in Bereishis 6:1). Perhaps Moshe was not stating that B'nei Yisroel were multitudes like the stars, but rather, they will multiply like the stars. Just as the visible stars may be a countable finite group, yet "potentially" infinite, B'nei Yisroel were a countable many, with the potential to become infinite. After all, has anyone ever calculated how many total Jews have lived in the history of the world?

Moshe Rabbeinu was speaking to B'nei Yisroel as they were on the verge of crossing over into Eretz Yisroel and realizing the ultimate goal of their deliverance from Egypt. This was a reminder of the star-like potential they were promised to realize following this auspicious moment in their history. It is therefore fitting that Moshe followed this statement with a blessing that HaShem will indeed multiply B'nei Yisroel thousand-fold, to develop them from a modestly small nation like the countable, visible stars, to a prolific nation like the infinite stars of the universe.

Wednesday, January 29, 2025

Korban Pesach in the Sky

I have been told in the past that I am probably the only person who finds Divrei Torah on Parshas Bo that are about astronomy and have nothing to do with the mitzvah of Kiddush HaChodesh. (For example, did you ever wonder which star Paaraoh was referencing when he said, "Ra'ah is against you ...," or did you recognize that the verse that says that no dogs barked at the Jews is also discussing an astronomical event that was significant to the Egyptian people of that time? These ideas are discussed at length in my new book, The Secrets of the Stars, available here.) In order to hold my unique title I would like to share a few thoughts about a fascinating comment by the Rokeach regarding the Korbon Pesach.

The pasuk informs us that the Pesach had to be a male ovine creature, but that it could be either a sheep or a goat. (Shemos 12:5) The Rokeach teaches that these two choices symbolized the astronomical events that occured on that miraculous night in Egypt.

Every month the sun appears to be in a different place in the sky relative to the background stars. In fact, every month it has moved from being juxtaposed in front of one constellation and then appears to be occupying another. For example, in the month of Nisan it is in the constellation T'leh (Aries, the Ram), but in the month Iyar it has moved to the constellation Shor (Taurus, the Ox). Since when the sun is visible it is daytime, this means that the constellation that the sun is occupying will be rising with the sun. This is considered to be the mazal of the month. (Rashi Berachos 11b; these positions have shifted since ancient times and no longer does the sun occupy these positions in these specific months) In the month of Nisan, the one of the Pesach years ago, the mazal that rose at sunrise, and was therefore perceived to be in control, was that of T'leh. Additionally, says the Rokeach, if one takes the numerical value of the Hebrew word T'leh and that for blood, "Dam", he will find that they are equal. (Rokeach Shemos 12:5)

The Rokeach continues to describe more about the celestial happenings and symbolism of that night. Every two hours another mazal appears to be rising from the east as the sun (and background stars) makes its way across the sky from east to west. On the night of the Pesach of Egypt the constellation that was rising from the east at nightfall was Moznayim (Libra, the Scales). At midnight, the time that Hashem exacted judgment on the Egyptians and killed their firstborns, the mazal rising from the east was G'di (Capricorn[us], the Goat). Thus, we find that T'leh and G'di were in positions of power during this plague and we therefore serve Hashem by offering these two animals, sheep and goats in His service. Additionally, blood (the numerical equivalent of T'leh as stated above) symbolizes the planet Mars and that is a representation of death and blood and it was at this time that death and murder was happening in Egypt.(Ibid.)

Perhaps, there is more symbolism than just what was stated above. Besides the T'leh, G'di, and Mars being expressed; it would seem that Moznayim, the Scales, were also displaying something very important. Just like the mazal that rises at daybreak is considered to have influence, so too, the one that rises in the evening is considered to exert some force. The mazal of Moznayim is symbolic of the scales of judgment and this evening certainly was one of judgment. (Midrash Tanchuma Haazinu 1)

Even more is that there are seven ancient planets: the sun, moon, Mercury, Venus, Mars, Jupiter and Saturn. Of these they can be split into two categories, the sun and moon in one and the other five planets in the other. Each of these entities is considered to rule over one (or two) of the 12 mazalos of the zodiac. Twelve obviously does not divide by seven evenly, so the method is not to give every planet an equal amount of mazalos to rule over. The sun and moon are each given one and the rest of the planets have two a piece. Mars has T'leh (Aries) as one of its mazalos. (Ibn Ezra Reishis Chachma 2) So, in addition to T'leh being powerful, its ruler (and planet whose symbolic expression of blood has an equivalent numerical value to itself) was also finding its expression.

Also of interest is where Mars was positioned that fateful night. Mars was to be found in the constellation D'li (Aquarius, the Water Bearer). D'li is the mazal of Klal Yisrael. (Ibn Ezra Shemos 31:18) The Rokeach teaches us that when the destructive deathly force of that night, the Mashchis, saw the blood of the Pesach on the doorposts he was confused and believed that death had struck those houses and he therefore turned away. (Rokeach Shemos 12:5) Mars and its death were prepared to strike even Klal Yisrael, in whose constellation Mars was occupying, but through the Dam, blood, of the mitzvah were saved

Friday, November 8, 2024

The Uncountable Stars

In this week's parsha (15:5) HaShem brings Avraham Avinu outside and tells him to observe the uncountable stars and tells him that his progeny will be likewise uncountable. Rashi there quotes a Midrash that states that HaShem removed Avraham from the atmosphere and placed him above the stars to observe them. R' Chaim Kanievsky questions, why was this necessary? Why was it not sufficient to simply look at the stars from where he was?

He answers that we are taught in the adjacent commentary to Rambam's Hilchos Yesodei HaTorah (3:8) that there are a finite number of stars visible from Earth, 1022 to be exact. Beyond the scope of our vision there exists an abundance of stars which are too many to be counted. Being shown the stars from Earth was simply not impressive enough. Avraham had to be removed from Earth in order to appreciate the true extent of the berachah.






Blogger Ari S.said...

The number 1,022 is also seen in Ibn Ezra's Reishis Chachma (on astrology). He cites Ptolemy just like the Rambam mentions in a few places (i.e. hilchos kiddush hachodesh) that his knowledge of astronomy comes from the Greek sources. Ptolemy (in the Almagest) does have this number. It is pretty clear that he (and the rishonim) were aware that there were many more. In fact, the way Ptolemy and Ibn Ezra cite it is to show how the constellations are formed. It seems that this number refers to the bigger and brighter stars.

The average person can see approximately 3 - 4,000 stars (the faintest being about magnitude 6). Perhaps, another idea expressed in the pasuk could be that it is impossible to count them at once. Some are below the horizon at times and others seasonal. Some are only seen at northern latitudes and others at southern. Maybe Avraham had to go high above in order to get an angle above them to see them at one time.

Jewish people have been dispersed throughout many countries during our exile. This is often to our benefit because it provides a defense mechanism. It is much more difficult for an enemy to ever annihilate us because of this. Maybe we are being taught that you will never be able to see all the Jews in one spot to count because they will be dispersed. In the ensuing pesukim of the covenant, there are many references to the exile.

Quality not Quantity

Firstly, let me let everyone know that, b"H, the book is finally almost ready to go to print! The cover and typesetting have been completed and we are just going through it very quickly to make sure that everything is in order. Keep your eyes open for it, hopefully it should be in stores in about a month or so!!!

In the Parsha we find that Avraham Avinu is informed by Hashem that his children will be comparable to the stars. Many commentators explain this to be a description of the characteristics of the children and not that it represents the number of offspring. Based on Rav Yehonasan Eibshitz's explanation I would like to offer the following short explanation.

Unlike planets which reflect the light of the sun, stars produce their own light. Due to processes of nuclear fusion happening in the center of the star, the entire star is illuminated and radiates brilliantly. So too, every member of Klal Yisrael shines in his own right. He is not shining because of "reflected light" from others, rather, he has a brilliant core that can brighten even the darkest places.

Additionally, from our perspective many of the stars are not visible. Many of them are too far from us and we are unable to perceive their light. Others have interstellar dust and debris that block their light from reaching us. This, too, is expressive of the inner beauty of the nishamos of Klal Yisrael. Even if they have strayed very far away and their glory cannot be seen on the outside, or if they have external inhibitions which do not allow for their light to be seen on the outside; nevertheless, their inner beauty is present and shines!

Lastly, in this week's Parsha, Avraham Avinu is told by Hashem to walk in front of Him and be perfect. The Rambam, Ramban, and many others explain that this perfection is the same mentioned by Hashem in Sefer Devarim when He commands Klal Yisrael to be perfect with Him. Included in that mitzvah is the commandment to refrain from predicting via astrology. The Rosh's son Rebbi Yehuda felt that this mitzvah represents the essence of the entire Torah and that the reason for the elongation of the exile is due to our lack of observance of this mitzvah. To understand why please feel free to
download a free copy of it here.

Friday, November 1, 2024

Sailing the Friendly Skies

Perhaps it was the fact that this week’s Parsha discusses a boat, but there was some interesting astronomical news this week that got me thinking about a certain passage from the Gemara in Horiyos (10a). There, the Gemara relays a story in which Rabban Gamliel and Rebbi Yehoshua were traveling on a ship. Rebbi Yehoshua had packed extremely durable food, whereas Rabban Gamliel packed meals befitting a standard seafarer. The ship was delayed and Rabban Gamliel’s supply was exhausted. Rabban Gamliel was only able to be sustained due to Rebbi Yehoshua’s careful planning. Rabban Gamliel inquired of Rebbi Yehoshua how he knew the journey would take so long. Rebbi Yehoshua responded:

".[כוכב אחד לשבעים שנה עולה ומתעה את (הספינות) [הספנים] ואמרתי שמא יעלה ויתעה [אותנו"

“There is a star that appears in seventy years and tricks the sailors. I said to myself that perhaps it will rise and trick us.”

It is common knowledge that ancient sailors were extremely dependent on astronomical knowledge in order to navigate. Without modern equipment such as GPS devices, the most accurate method of determining one’s position is based on the stellar positions. The stars move through the sky in very specific patterns. Some are always in the north and others in the south. With this knowledge, sailors can navigate the seas. Additionally, apparent celestial position changes based on latitude, so one can determine his latitude with extreme precision based on how high specific stars are from the horizon. Thus, if a “tricky” star were to “appear” it could be disastrous to the sailors because it could send them way off course.

Rashi explains that the celestial object mentioned refers to a star that rises once every seventy years. This star sometimes appears in the north and sometimes in the south. If the sailor, unaware of this star’s nature, were to see it in the north at the beginning of the journey and later, unbeknownst to him, it would change position then he would think he was traveling in one direction but would actually be going in the opposite direction. Rebbi Yehoshua was nervous that this would occur to them while they were on their journey so he packed extra durable food.

While much has been written throughout the ages expressing the symbolic meaning behind this passage, it is very unclear as to the identity of this “star” in the plain meaning of the text. “Regular” stars have set positions in the sky and cannot change from north to south, so it seems unlikely that it could be a regular star. The planets’ orbits do not have them rising once every seventy years and switching from north to south during that time so they are also not viable options.

At first glance one may think that this star is a comet. Comets move across the sky and could theoretically be good candidates for what is being discussed. There is only one comet that has a short orbital period that is easily seen by the naked eye and interestingly it happens to appear once every 75-76 years, Comet Halley (Halley’s Comet). This comet has been recorded by ancient astronomers at least as far back as 240 BCE, so it had been sighted prior to the time of Rebbi Yehoshua. If Rebbi Yehoshua was rounding the 75-76 years and referencing it as 70, then perhaps he was discussing this comet. This would be exceptionally fantastic because history gives credit to Edmund Halley as figuring out that the various comets recorded throughout history at 75-76 year intervals were all the same object and that this is that comet’s periodicity was 75-76 years. This “discovery” would not occur until over 1,500 years after Rebbi Yehoshua in the year 1705 CE!!!

There is one major problem with this assertion, though. The only arrival of Comet Halley during Rebbi Yehoshua’s lifetime would have been in 66 CE. Rabban Gamliel would have been an extremely young child at this time and in the ensuing parts of the story he is displayed as being older. (See Rashash, Pesachim 74a) Additionally, it would seem that he already achieved the title Rabban meaning that he was the Nasi and that did not happen until after the destruction of the second Beis Hamikdash which occurred in 70 CE. (See Gittin 56b; also see Seder Hadoros’ biographical synopsis of Rebbi Zeira for a discussion of the usage of titles in the Gemara indicating that the individual had already achieved that status at the time being referenced by the Gemara.) Thus, this story had to have happened well after Comet Halley’s appearance in 66 CE. To assert that Rebbi Yehoshua did not remember that the last appearance was in 66 CE and, therefore, was nervous that it would appear during the journey; or that he thought it would come sooner than 75 years this particular instance is unlikely. Rebbi Yehoshua mentions the 70 year interval in his statement; thereby displaying that he was aware of the orbital period. If he was aware of this fact, then it is unreasonable that he would not have remembered the last magnificent appearance of this comet which would have happened in his own lifetime and that he felt its periodicity was not subject to change.

I concede that I do not know what the identity of the object that Rashi is describing, however, I would like to suggest another approach to this passage. As I will explain, it would appear that Rashi had a variant text of this passage and I would like to offer a suggestion based on the text present in the standard editions of Gemara that we currently have. Perhaps, Rebbi Yehoshua was not stating that there is a star that appears every seventy years, rather, he was stating that there will be a star to appear in seventy years. He was not discussing a recurring event; he was mentioning that there was going to be a one time event that would happen in seventy years from the time being discussed in the Gemara. If this is, in fact, the case then one may ask why was Rebbi Yehoshua concerned that this star would appear prior to its seventy year date of arrival? The answer is that although based on Rebbi Yehoshua’s calculations the star would be coming in seventy years, nevertheless he may have realized that there was a margin of error in his calculations that would allow for this star to appear prior to that time. Therefore, he stated that there is a star destined to appear in seventy years, but because it was possible that it would appear sooner, he brought along extra provisions. The reason why this suggestion seems more likely based on the text in our Gemara is because the language used is:

"כוכב אחד לשבעים שנה."

and not:

"כוכב אחת לשבעים שנה."

The difference is that the text we have has the word “אחד” “one” in the masculine form and not “אחת” in the feminine. While this may seem like a minor variance, in truth it makes a world of a difference. If in the feminine it would indicate that the “one” is referring to the implicit, “פעם” “occurrence” and it is as if it says, “פעם אחת” “one occurrence.” Note that Rashi has this word in the feminine in his commentary to this passage. This reading of the text would be stating that the star appears once every seventy years and is a recurring event. Since in our text “one” is in the masculine form, it is clearly referring to the star and not referring to the periodicity of the star being seventy years. Thus, the translation of the entire sentence becomes, “One star will appear in seventy years, etc.” and is no longer, “A star appears once every seventy, etc.”

If this is the case, what then could this “star” be? We have ruled out regular stars, planets, and comets already, so what is left to be considered? Perhaps, Rebbi Yehoshua was referring to a new star appearing out of nowhere. Although uncommon, this has happened in extremely rare instances. When this has occurred it has not been that a brand new star was formed, rather, there was a star that was too faint to be seen by the naked eye which then brightened and became visible. At the end of large stars’ lives they experience an event called a supernova. Supernovae are essentially massive explosions during which time tremendous energy and radiance is emitted from dying stars. Supernovae that have become visible to the naked eye have occurred only a handful of times through recorded history.Over several months, these new stars then faded away and disappeared, only to be seen via telescope. Interestingly, the very first known one recorded in history happened in 185 CE. This is now referred to as SN 185 and made the news this week as observations by NASA’s Spitzer and WISE telescopes uncovered many more of the dynamics of how this supernova unfolded. Although Rebbi Yehoshua did not live until 185 CE, he would certainly have been alive and well 70 years prior to this and could easily have been aboard a ship with Rabban Gamliel in 115 CE. Keep in mind that the Gemara does not state that the actual reason for the delay of journey was because the star actually appeared, just that that was the reason Rebbi Yehoshua was prepared for such a delay. Supernovae are very unpredictable, perhaps leaving Rebbi Yehoshua doubting his accuracy and leaving a margin of error. In fact, if Rebbi Yehoshua was able to predict this one, his seventy year margin of error is far more accurate than even today’s predictions for supernovae!!! If this is the case, it is also astounding because even the ability to predict or understand supernovae is not considered to be known by man until the twentieth century and as previously mentioned, the accuracy with which Rebbi Yehoshua predicted this one is still not attainable by contemporary scientists!!!

The question then arises, why could such a star cause such confusion as to mislead a sailor. The rest of the sky would still have the same appearance and the sailor would just see an extra star, but would not head in the wrong direction. Upon further review, however, one can see that SN 185 may have actually been a little more confusing than just appearing as an additional star. The North Star and nearby Big Dipper are integral to celestial navigation as they are always positioned in the north. SN 185 occurred in the ancient constellation of Centaurus. In ancient times most people were not as familiar with those southern constellations since they can only be seen from more southerly parts of Earth. The area of Centaurus where SN 185 appeared would normally not be able to be confused with the Big Dipper and North Star, however, because they appear to have different configurations. The difference in configuration seems so apparent, but in fact is only so striking because this region of Centaurus is missing one bright star that appears in the Big Dipper. SN 185 flared up and appeared in that region so it is possible that a sailor would have glanced to the south quickly and mistaken this constellation for the Big Dipper!


The Big Dipper and North Star in the north:



Centaurus (prior to SN 185's appearance and post its disappearance) in the south:




Centaurus as it would appear with SN 185 in the year 185CE: