Bearing to Yerushalayim and Zmanim Map 2.0

Vintage Map with CompassThe availability of the Bearing to Yerushalayim and Zmanim Map was originally announced on December 30, 2007. At the time there were a number of bugs related to the Google Map API. These bugs were reported to Google and eventually fixed. Since that time, the only change was a minor JavaScript fix for IE. The Bearing to Yerushalayim worked, but the zmanim tabs had a major issue because the timezone calculated was done based on the user’s current browser timezone. This made it tricky to check zmanim in a different location or timezone than the user’s current timezone.Zmanim tab using timezonesI recently updated the map to look-up the actual timezone of the latitude and longitude selected by the user. This was implemented by doing a look-up at the geonames.org timezone web-service. The timezone is passed to the Zmanim API and used to generate the XML output of a list of daily zmanim that is displayed in the map. Since the Olson timezone database changes a few times a year, there will almost certainly be cases where the proper timezone can’t be determined. Some of these are changes of timezone names, such as the change from Asia/Calcutta to Asia/Kolkata (my host will not run the TZ Updater tool). In these cases, a simple mapping between the old and new was added to the map. In cases where the timezone can’t be determined the timezone will default to GMT. Ocean locations within 10 km of land will use the closest landmass, but anywhere beyond 10 km will default to GMT. One issue with using the geonames.org webservice, is that when it is down, the map will timeout. I experimented with various ways of dealing with this, but unless my host updates the Java version from 1.4, they are too complex to use at this time.

See the Technical Information about the Bearing to Yerushalayim Map post for technical details about the original implementation.

Zmanim Calendar Generator Supports 2007 DST Changes

Sunrise CalendarThe Java version on the server was just updated to JDK 5.0 Update 11 and now supports the US 2007 DST Changes mentioned in the previous post. This means that Excel zmanim calendars generated by this site will have the proper daylight savings time for zmanim.

Zmanim Calendar Generator Does Not Yet Support 2007 DST Changes

Sunrise CalendarAs you may know, the U.S. is changing the Daylight Saving Time rules this year due to the Energy Policy Act of 2005. The server currently hosting this site does not yet have the Java patch for this. This means that from the second Sunday in March (the 11th) until the last Sunday in March (the 25th), calendars generated from the Zmanim Calendar Generator will show the zmanim in standard time and not daylight savings time (DST). The same issue will happen in the fall from the last Sunday in October (the 28th) till the first Sunday in November (the 4th). The Java version used by the server should be patched within the next week or 2 to the latest Java 5 (JDK 1.5) version to solve this problem.