Lunar calendar traces of its origin in the earlier lunar calendar, which continued to be used alongside it for religious and agricultural purposes. Present-day lunisolar calendars include the Chinese, Hindu, and Thai calendars. Synodic months are 29 or 30 days in length, making a lunar year of 12 months about 11 days shorter than a solar year. Some lunar calendars do not use intercalation, such as most Islamic calendars. For those that do, such as the Hebrew calendar, the most common form of intercalation is to add an additional month every second or third year. Some lunisolar calendars are also calibrated by
Dundrod Circuit the 2017 Ulster Grand Prix. The race record for the Dundrod Circuit is an average speed of set by Bruce Anstey during the 2017 Ulster Grand Prix. The lap record for the RAC Tourist Trophy on the Dundrod Circuit is 4 minutes and 42 seconds at an average speed of 94.67 mph (152.3582 km/h) held by Mike Hawthorn driving a Jaguar D-Type set during the 1955 RAC Tourist Trophy. The race record for the RAC Tourist Trophy on the Dundrod Circuit is 7 hours, 3 minutes and 12 seconds an average speed of 88.32 mph (142.139 km) for 84 laps