12/28/2004: More on the tsunami...
or rather, the quake that caused it. Apparently the quake had its epicenter just a little west of the western tip of Sumatra, and I'm reading reports that there has been significant earth movement as well--apparently the entire island of Sumatra has shifted physical position (in simpler terms, moved) about 100 feet to the southwest. On a global scale, that might not sound like a lot, but it's enough movement that any activities in that area involving precise positional data (astronomical observations, navigation (including high precision charts and maps), and so on) will have to take account of that shift.
UPDATE: An acquaintance who works for the USGS seismological lab in Pasadena, CA, informs me that the original reports of a 100 foot displacement was apparently mistaken. Right now the hypothesis is that the mistake originated with CNN's reports. According to him, right now the current maximum displacement has been measured at about 10 feet.
Which is, come to think of it, still quite a distance to move something as big as Sumatra.
Len on 12.28.04 @ 09:14 AM CST