Google is “celebrating” the end of the 13th Baktun, or the last cycle of the Mayan calendar, which of course, legend has it, is supposed to bring the end of the world. So far, so good.

Google is showing the above doodle in many parts of the world, though not everywhere. For example, it’s not visible on the Google Canada homepage. Here in the U.S. Google has skipped the doodle in favor of honoring the victims of the terrible tragedy in Newtown, Connecticut, which took place a week ago. The U.S. homepage is displayed as normal, with the addition of a green ribbon, which says upon mouseover, “Remember those lost at Sandy Hook Elementary School.”

Google talks about the doodle on its Latin America blog (rough translation via Google Translate):

“Mathematics, science and astronomy are issues that have always passionate. So with our doodle today, celebrating the end of the 13th Baktun of the Mayan calendar long count system. But what does this mean? Mayans were advanced mathematicians and astronomers who calculated the cycles of the moon and sun. They had very specific ways of measuring time, one of these ways is the Long Count system, in which each year has 18 months with 20 days. The system also includes other units as the Katun, equivalent to 20 years of our calendar, and Baktun, which is equivalent to 394 years.”

“The importance of reaching the 13th Baktun, is that different from what happens with our schedule, there is a 14 ° Baktun. The count returns to zero. But unlike all the disaster stories that will surely have heard, at the end of the 13th Baktun, as happens every time just on Sunday in our calendars, it becomes thus begins Monday and a new week. Those who have studied the issue, explaining that this is because it works its scheduling system, and, although it represents the end of a cycle, it means something catastrophic.”