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
Pioneer 3 direct ascent trajectory, the odds of hitting the Moon were slim. However, a lunar flyby rather than impact would still be considered a successful mission. The flight plan called for the "Pioneer 3" probe to pass close to the Moon after 33.75 hours and then go into solar orbit. The Juno II lifted from LC-5 at 12:44 AM on December 6. Launch went entirely according to plan until first stage cutoff, when the engine cut off 3.7 seconds early due to a failure of the propellant depletion sensors, leaving a velocity shortfall of several hundred feet per second. The injection