Five Years Since Surgery

Source
http://www.uwmc.uwc.edu/geography/demotrans/demtran.htm

Wow!  It's been five years since I started this blog.  That was a few months after surgery, which occurrred, if I remember correctly,  on the day of the winter solstice.   One of my posts showed a survival  (survivorship ) curve which flattened out after five years.  The slope  (loss rate) likely approaches that of the general population (with some age adjustments).   This area of statistics is called survival analysis .   Survivorship curves come in several shapes. Here are some examples for different times and countries.  The mid-life slope for Europe is about 0.5% per year. 

Four Years Since Surgery

Lunar Eclipse (Nasa.gov)

Courtesy of the US Naval Observatory Data Services, yesterday was Julian Day Number 2455916.5 . The Julian date for CE 2011 December 21 00:00:00.0 UT is JD 2455916.500000. The JDN, or JD, is simply the count of days since a given day in the past .  The year, month, day of month conversion is more complicated since the number of days in a solar year is 365.25 - 0.0078103 (J2000) and different from the fixed star frame sidereal year  of 365.25 +0.006363004, as of J2000). days. Subtracting  the JDNs  of two calendar dates gives the number of days between those dates. Of course, one must have an accepted algorithm for converting from calendar dates to JDNs  (and back). 

The official date of my surgery was December 21, 2007  -  JDN 2454455.5 which gives 1,461 days since surgery.   Since 1, 461 modulo 365 is one,  there was a leap year somewhere along the survival curve. :)  

Today, the winter solstice  occurs at 05:30 UTC.  In 2007 it occurred 06:08 UTC.    Happy Survival Day...the days get longer for the next 6 months or so - nice thought. 
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Rosh Hashana & The Dead Sea Scrolls On The Web

Rosh Hashana (The "head" of the year) is a Jewish  holiday.  Today is the first day of the year 5772 according to the Hebrew Calendar.    The epoch or reference date of the hebrew calendar is the date of the creation of the universe  -  the Anno Mundi.    Around 160 CE, Jewish scholars worked backwards from "known" events and used time periods mentioned in the Hebrew bible and calculated "year zero" at around 3,920 years before their current time.  So if we are in 2011 CE,  then we get 2011-160+3920 =  5771.  Seems right. 

You won't have to travel spatially to Israel to see the Dead Sea Scrolls.   The Israel Museum, Jerusalem and Google have a project to digitize them, and make them available to all online.   The Official Google Blog has a post  about the project as well.   As of now, you can click on the Great Isaiah scroll and get images and translations to English of the text.   The scrolls were discovered in caves in the Dead Sea area which is usually hot and dry.  Most of the scrolls are badly fragmented - a few are almost complete.  The scrolls were carbon dated in the 1990s with calibrated ages for the oldest scrolls at about 300 BCE  (about 2,300 years ago).    These are the oldest known surviving copies of the Hebrew bible and related texts.

The Hebrew bible starts with Genesis, the creation of the universe.  The biblical creation myth is one of many.   No ancient one is close to the scientific value for the age of the universe.  The Chinese and ancient Egyptians came up with ~40,000 years.  The Hindu's were close at 4.5 billion, but then decided to multiply by fifty. Still, it's pretty good.   Christian estimates range from about 9,000 to 6,000 years.