Explore Jewish time through astronomy.
Netz HaChamah: Sunrise
Sunrise, the solar limb and local horizon in calculations of Netz HaChamah.
The term
Netz HaChamah names sunrise in Jewish time terminology. The observable appearance of the Sun depends on the eastern horizon and the solar disc, rather than on a clock time that is fixed throughout the year.
Astronomy and interpretation
An astronomical sunrise calculation solves for a defined solar altitude or limb crossing at an observer location. Refraction, elevation and obstruction choices change that event. Selecting the relevant event for halachic use is a separate question.
Use in Jewish Cosmology
The Sun explorer lets you inspect the horizon, solar position and rise event. The Halachic Times view applies saved definitions to the selected day. Use these tools to compare assumptions, not to infer that one computed convention is a universal ruling.
Explore related concepts
About Jewish Cosmology
Jewish Cosmology is an interactive research and educational web application connecting Hebrew dates, traditional Jewish calendar calculations and halachic concepts of time with the observable motions of the Sun, Moon and planets, astronomical seasons and eclipses.
Models, terminology and limitationsHalachic times are unverified, have no rabbinic approval, and must not be relied upon for practical halachic decisions unless and until an appropriate authority approves them.