Sanhedrin 13 - December 30, 29 Kislev

How is the calculation to determine whether or not to intercalate the year based on the equinox performed? Is it determined by the autumnal equinox or the spring equinox? Does all of Sukkot need to fall in the autumn, or is it sufficient if just one day (the last) is in the autumn season? Additionally, is the equinox considered the last day of the previous season or the first day of the upcoming season? These questions are the subject of debate among the Tannaim. How many elders are required for semicha on the bull offering? Rabbi Yehuda holds that five are needed, while Rabbi Shimon says three. From which verses in the Torah does each derive their opinion? Another braita mentions "semicha" and "semicha of the elders"—one of which is interpreted as referring to the ordination of a rabbi. From where do we derive that three judges are required, and is it truly the case that it can only be done in the presence of three?