The Daf Yomi cycle just finished studying Masechet Rosh Hashanah. Mazal tov to all those who have completed this study! In Masechet Rosh Hashanah observations of the Moon play a very significant role. A major topic of study in this tractate is how the ancient Jewish “calendar” worked. In fact, it was not really a…
Category: Celestial Sphere / Visible Sky
Black Holes in Pesachim
The very first line of Pesachim focuses attention on one of astronomers’ favorite topics: light! Or does it?
Shavuot, Philo, Astronomy and Pythagoreans
The first century CE Jewish philosopher Philo of Alexandria, in glowing terms, describes the holiday of Shavuot and its underlying reasons based on mathematics – and astronomy!
The Menorah and Planets
Chanukah is an opportune time to share this interesting midrash about the Menorah and planets…
HaAdam Al HaYareach (Man on the Moon) Part 3
Rav Kasher answers the question, from a Torah point of view… Is one even allowed to go to the Moon?
In the less well known Pirkei DeRabbi Eliezer we find a less ominous, more astronomy focused talmudic take on eclipses…
Will the Real Equinox(+60) Please Stand Up?
Why do we annually begin saying ותן טל ומטר on Dec. 4th or 5th when the Talmud and Shulchan Aruch say otherwise?
Abraham and the First Planetarium
In Parshat Lech Lecha, we find Genesis 15:5, a great verse for astronomical commentaries and homiletics, for fairly obvious reasons: וַיּוֹצֵ֨א אֹת֜וֹ הַח֗וּצָה וַיֹּ֙אמֶר֙ הַבֶּט־נָ֣א הַשָּׁמַ֗יְמָה וּסְפֹר֙ הַכּ֣וֹכָבִ֔ים אִם־תּוּכַ֖ל לִסְפֹּ֣ר אֹתָ֑ם וַיֹּ֣אמֶר ל֔וֹ כֹּ֥ה יִהְיֶ֖ה זַרְעֶֽךָ׃ He took him outside and said, “Look toward heaven and count the stars, if you are able to count…
The First Festival of Light
Chanukah is often referred to as the Festival of Light(s). But it is not the first Festival of Light in the world, as the Talmud tells us.