Astronomy of Qumran: Further Considerations

Abstract

This paper is part of an ongoing debate regarding the theory raised a year ago by Dennis Duke and Matthew Goff in an attempt to re-explain the numerical values found in the Aramaic Astronomical Book (aab). According to their proposal, the composers of the aab or their sources computed the times of lunar visibility and invisibility using the phenomenon of lunar elongation. In this article, I accept Duke and Goff’s argument that their theory does not contradict the data preserved in the fragments of the scrolls of the aab. However, I demonstrate that their theory is unnecessarily complicated and that their proposal both ignores knowledge of physics available to the authors of the aab while making use of knowledge that neither the authors of the aab nor their sources obtained. Therefore, I suggest accepting Duke and Goff’s theory as a modern explanation of the astronomy of the aab, but not as a historical reconstruction.

The First Jewish Astronomers: Lunar Theory and Reconstruction of a Dead Sea Scroll

“…No explicit estimation of the draconitic month was preserved in cuneiform tablets, although it can be derived from the Saros cycle and later from the ACT tables and procedure texts that compute the moon's distance to the ecliptic. Nevertheless, we do find very accurate values for the sidereal month by the fifth or fourth century BCE (Hunger and Pingree 1999) and earlier (Ratzon 2016). If astronomical accuracy was the primary concern, we might have expected the numbers 27 or 28 as approximations, as they are round, astronomically more accurate (at least 27 is more accurate), and have Babylonian precedents (for example BM 45728 uses a 27-day sidereal month and the Babylonian Intercalation Scheme uses a 28-day sidereal month).…”

“…See their response in Duke and Goff 2016. Recently, I offered a new reconstruction for the pattern of lunar visibility and invisibility in the Aramaic AB (see Ratzon 2016a).…”