The 1670 calendar included an extra month unnecessarily, added to hide other errors and to bring the lunar months in line with the solar year. Verbiest suggested the errors should be corrected, including removing the extra month. This was an audacious move, as the calendar had been approved by the emperor himself. Fearing the emperor's response, the observatory officials begged him to withdraw this request, but he responded: "It is not within my power to make the heavens agree with your calendar. The extra month must be taken out." Much to their surprise, the emperor after studying the research, agreed, and it was done.